scholarly journals β-Cell Induction In Vivo in Severely Diabetic Male Mice by Changing the Circulating Levels and Pattern of the Ratios of Estradiol to Androgens

Endocrinology ◽  
2014 ◽  
Vol 155 (10) ◽  
pp. 3829-3842 ◽  
Author(s):  
Akari Inada ◽  
Oogi Inada ◽  
Nobuharu L. Fujii ◽  
Kei Fujishima ◽  
Tetsuichiro Inai ◽  
...  
Keyword(s):  
Blood Glucose ◽  
Male Mice ◽  
Β Cells ◽  
Β Cell ◽  
Glucose Levels ◽  
Blood Glucose Levels ◽  
Severe Diabetes ◽  
Cell Induction ◽  
Circulating Levels

Abstract Previously we have generated transgenic (Tg) mice developing severe diabetes early in life with a profound depletion of β-cells with β-cell-directed expression of inducible cAMP early repressor-Iγ. Only male mice continue to demonstrate hyperglycemia throughout life. To investigate this sexual dimorphism, we treated severely diabetic male Tg mice with orchiectomy (ORX) or 17β-estradiol (E2) pellet implantation alone or in combination with ORX and E2-implantation to change the circulating levels and patterns of the ratio of estradiol to androgens. In the Tg-ORX group, the blood-glucose levels decreased to a certain level within several weeks but never reached the female Tg-control level. In contrast, the Tg-ORX+E2 or Tg-E2 group showed a more rapid drop in blood glucose to the basal level with a substantial increase in β-cells, thus preventing the occurrence of severe diabetes in the male mice. The β-cells, not only within islet but also in and adjacent to ducts and scattered β-cell clusters, were strongly induced by 1 week after treatment, and the islet morphology dramatically changed. Enhanced β-cell induction in the ducts occurred concomitantly with markedly increased levels of pancreatic duodenal homeobox-1 and related transcription factors. The glucose-lowering and β-cell-increasing effects were independent of the age at which the treatment is started. These data provide evidence that the circulating level of E2 and the ratio of E2 to T greatly affect the blood glucose levels, the β-cell induction, and the islet morphology in diabetic male Tg mice. This novel mechanism offers great potential for developing strategies to increase the number of β-cells in vivo.

scholarly journals Development and Characteristics of Pancreatic Epsilon Cells

2019 ◽  
Vol 20 (8) ◽  
pp. 1867 ◽  
Author(s):  
Naoaki Sakata ◽  
Gumpei Yoshimatsu ◽  
Shohta Kodama
Keyword(s):  
Transcription Factors ◽  
Blood Glucose ◽  
Endocrine Cells ◽  
Current Evidence ◽  
Β Cells ◽  
Β Cell ◽  
Glucose Levels ◽  
Blood Glucose Levels ◽  
Ghrelin Gene ◽  
Pancreatic Endocrine Cells

Pancreatic endocrine cells expressing the ghrelin gene and producing the ghrelin hormone were first identified in 2002. These cells, named ε cells, were recognized as the fifth type of endocrine cells. Differentiation of ε cells is induced by various transcription factors, including Nk2 homeobox 2, paired box proteins Pax-4 and Pax6, and the aristaless-related homeobox. Ghrelin is generally considered to be a “hunger hormone” that stimulates the appetite and is produced mainly by the stomach. Although the population of ε cells is small in adults, they play important roles in regulating other endocrine cells, especially β cells, by releasing ghrelin. However, the roles of ghrelin in β cells are complex. Ghrelin contributes to increased blood glucose levels by suppressing insulin release from β cells and is also involved in the growth and proliferation of β cells and the prevention of β cell apoptosis. Despite increasing evidence and clarification of the mechanisms of ε cells over the last 20 years, many questions remain to be answered. In this review, we present the current evidence for the participation of ε cells in differentiation and clarify their characteristics by focusing on the roles of ghrelin.

Glucose regulation of insulin gene expression in pancreatic β-cells

2008 ◽  
Vol 415 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Sreenath S. Andrali ◽  
Megan L. Sampley ◽  
Nathan L. Vanderford ◽  
Sabire Özcan
Keyword(s):  
Gene Expression ◽  
Transcription Factors ◽  
Blood Glucose ◽  
Insulin Gene ◽  
Β Cells ◽  
Β Cell ◽  
Insulin Synthesis ◽  
Glucose Levels ◽  
Blood Glucose Levels ◽  
Insulin Gene Expression

Production and secretion of insulin from the β-cells of the pancreas is very crucial in maintaining normoglycaemia. This is achieved by tight regulation of insulin synthesis and exocytosis from the β-cells in response to changes in blood glucose levels. The synthesis of insulin is regulated by blood glucose levels at the transcriptional and post-transcriptional levels. Although many transcription factors have been implicated in the regulation of insulin gene transcription, three β-cell-specific transcriptional regulators, Pdx-1 (pancreatic and duodenal homeobox-1), NeuroD1 (neurogenic differentiation 1) and MafA (V-maf musculoaponeurotic fibrosarcoma oncogene homologue A), have been demonstrated to play a crucial role in glucose induction of insulin gene transcription and pancreatic β-cell function. These three transcription factors activate insulin gene expression in a co-ordinated and synergistic manner in response to increasing glucose levels. It has been shown that changes in glucose concentrations modulate the function of these β-cell transcription factors at multiple levels. These include changes in expression levels, subcellular localization, DNA-binding activity, transactivation capability and interaction with other proteins. Furthermore, all three transcription factors are able to induce insulin gene expression when expressed in non-β-cells, including liver and intestinal cells. The present review summarizes the recent findings on how glucose modulates the function of the β-cell transcription factors Pdx-1, NeuroD1 and MafA, and thereby tightly regulates insulin synthesis in accordance with blood glucose levels.

scholarly journals Antidiabetes of Combination of Fractionated-extracts of Andrographispaniculata and Centellaasiatica in Neonatal Streptozotocin-induced Diabetic Rats

2020 ◽  
pp. 312-322
Author(s):  
Reni Ariesta ◽  
La Ode Muhammad Fitrawan ◽  
Agung Endro Nugroho ◽  
Suwidjiyo Pramono
Keyword(s):  
Blood Glucose ◽  
Diabetic Rats ◽  
Β Cells ◽  
Β Cell ◽  
Antioxidative Effect ◽  
Glucose Levels ◽  
Blood Glucose Levels ◽  
Pancreatic Insulin ◽  
Treatment Of Diabetes ◽  
Old Rats

Many medicinal plants are widely grown in South- and Southeast Asia countries. Some of them are traditionally used for treatment of diabetes mellitus such as Andrographispaniculata and Centellaasiatica. In the study, we provided fractionated-extracts of A. paniculata and C. asiatica to increase the concentration of their active compounds and eliminate unexpected substances. The aim of the study was to evaluate the antidiabetes effect of the combination of their fractionated-extracts in male neonatal streptozotocin (STZ)-induced diabetic rats. In the study, diabetes was injected intraperitoneally 90mg.kg-1 BWSTZ  to two day-old rats. At the age of three months, the rats were administered with the combination of both fractionated-extracts for 14 consecutive days. We evaluated antidiabetes with parameters of blood glucose levels, morphology of pancreatic islet, β-cell density as well as immunohistochemical pancreatic insulin. The levels of MDA, SOD and GPx were also determined about oxidative stress change after treatment with the combination. In the study, the combination succeeded to lower the blood glucose level in neonatal STZ-induced diabetic rats. Inline with fact, improvement of rat pancreatic islets and β cells density, as well as moderate restoration of pancreatic insulin, were observed after treatment with the combination. The substance could decrease the level of MDA, and increase the levels of SOD and GPx. In conclusion, the combination of fractionated-extracts of A. paniculata and C. asiatica exhibited potential antidiabetic effect to its antioxidative effect in male neonatal STZ-induced diabetes rats.

Efek Ekstrak Etanol Kulit Petai (Parkia speciosa Hassk) Terhadap Penurunan Kadar Glukosa Darah Mencit Jantan

2018 ◽  
Vol 3 (1) ◽  
pp. 1
Author(s):  
Verawaty Verawaty ◽  
Dhea Claudia Novel
Keyword(s):  
Blood Glucose ◽  
Ethanol Extract ◽  
Negative Control Group ◽  
Positive Control ◽  
Negative Control ◽  
Control Group ◽  
Male Mice ◽  
Glucose Levels ◽  
The Third ◽  
Blood Glucose Levels

<p>Penelitian ini bertujuan untuk melihat pengaruh pemberian ekstrak etanol kulit petai (Parkia speciosa Hassk) terhadap penurunan kadar glukosa darah mencit jantan yang diinduksi aloksan. Hewan percobaan dibagi atas 5 kelompok diantaranya kelompok kontrol negatif, kelompok kontrol positif,dosis I (280 mg/kgBB mencit), dosis II (560 mg/kg BB mencit), dosis III (840 mg/kg BB mencit). Penelitian dilakukan selama 21 hari. Persentase penurunan kadar glukosa darah mencit jantan setelah diberikan ekstrak etanol kulit petai pada hari ke-21 adalah dosis I (77,52 %) lebih besar dibandingkan dengan dosis II (69,5 %) dan dosis III (73,37 %). Data yang diperoleh dianalisis dengan uji Two Way Anova dengan program SPSS 17. Hasil penelitian ini menunjukkan bahwa pemberian ekstrak etanol kulit petai untuk tiga variasi dosis menyatakan perbedaan yang bermakna secara statistik terhadap penurunan kadar glukosa darah mencit jantan.</p><p><em>Petai (Parkia speciosa Hassk) has a compound β-sitosterol and stigmasterol that have efficacy to decreased blood glucose levels. This study aimed to determine the effect of ethanol extract of petai peel for decrease blood glucose levels of male mice induced by alloxan. Experimental animals were divided into 5 groups including negative control group, positive control group, the first dose (280 mg/kg in mice), the second dose (560 mg/kg in mice), the third dose (840 mg/kg in mice). The study was conducted for 21 days. After 21 days, the result found that the percentage of blood glucose levels after the male mice given the ethanol extract of petai peel was, the first dose (77.52%) biger than the second dose (69.5%) and the third dose (73.37%). The data obtained were analyzed by Two Way ANOVA using SPSS 17. The results showed that have signicantly difference between three dose variation of ethanol extract of petai peel in blood glucose levels.</em></p>

scholarly journals Oral DhHP-6 for the Treatment of Type 2 Diabetes Mellitus

2019 ◽  
Vol 20 (6) ◽  
pp. 1517 ◽  
Author(s):  
Kai Wang ◽  
Yu Su ◽  
Yuting Liang ◽  
Yanhui Song ◽  
Liping Wang
Keyword(s):  
Diabetes Mellitus ◽  
Type 2 Diabetes ◽  
Type 2 Diabetes Mellitus ◽  
Blood Glucose ◽  
Enzymatic Activity ◽  
Glucose Levels ◽  
Blood Glucose Levels

Type 2 diabetes mellitus (T2DM) is associated with pancreatic β-cell dysfunction which can be induced by oxidative stress. Deuterohemin-βAla-His-Thr-Val-Glu-Lys (DhHP-6) is a microperoxidase mimetic that can scavenge reactive oxygen species (ROS) in vivo. In our previous studies, we demonstrated an increased stability of linear peptides upon their covalent attachment to porphyrins. In this study, we assessed the utility of DhHP-6 as an oral anti-diabetic drug in vitro and in vivo. DhHP-6 showed high resistance to proteolytic degradation in vitro and in vivo. The degraded DhHP-6 product in gastrointestinal (GI) fluid retained the enzymatic activity of DhHP-6, but displayed a higher permeability coefficient. DhHP-6 protected against the cell damage induced by H2O2 and promoted insulin secretion in INS-1 cells. In the T2DM model, DhHP-6 reduced blood glucose levels and facilitated the recovery of blood lipid disorders. DhHP-6 also mitigated both insulin resistance and glucose tolerance. Most importantly, DhHP-6 promoted the recovery of damaged pancreas islets. These findings suggest that DhHP-6 in physiological environments has high stability against enzymatic degradation and maintains enzymatic activity. As DhHP-6 lowered the fasting blood glucose levels of T2DM mice, it thus represents a promising candidate for oral administration and clinical therapy.

scholarly journals Glycemic Variability in Diabetes Increases the Severity of Influenza

mBio ◽  
2020 ◽  
Vol 11 (2) ◽  
Author(s):  
Rebecca J. Marshall ◽  
Pornthida Armart ◽  
Katina D. Hulme ◽  
Keng Yih Chew ◽  
Alexandra C. Brown ◽  
...  
Keyword(s):  
Blood Glucose ◽  
Glycemic Variability ◽  
Endothelial Barrier ◽  
Glucose Levels ◽  
Blood Glucose Levels ◽  
Severe Influenza ◽  
Increased Risk ◽  
History Of

ABSTRACT People with diabetes are two times more likely to die from influenza than people with no underlying medical condition. The mechanisms underlying this susceptibility are poorly understood. In healthy individuals, small and short-lived postprandial peaks in blood glucose levels occur. In diabetes mellitus, these fluctuations become greater and more frequent. This glycemic variability is associated with oxidative stress and hyperinflammation. However, the contribution of glycemic variability to the pathogenesis of influenza A virus (IAV) has not been explored. Here, we used an in vitro model of the pulmonary epithelial-endothelial barrier and novel murine models to investigate the role of glycemic variability in influenza severity. In vitro, a history of glycemic variability significantly increased influenza-driven cell death and destruction of the epithelial-endothelial barrier. In vivo, influenza virus-infected mice with a history of glycemic variability lost significantly more body weight than mice with constant blood glucose levels. This increased disease severity was associated with markers of oxidative stress and hyperinflammation both in vitro and in vivo. Together, these results provide the first indication that glycemic variability may help drive the increased risk of severe influenza in people with diabetes mellitus. IMPORTANCE Every winter, people with diabetes are at increased risk of severe influenza. At present, the mechanisms that cause this increased susceptibility are unclear. Here, we show that the fluctuations in blood glucose levels common in people with diabetes are associated with severe influenza. These data suggest that glycemic stability could become a greater clinical priority for patients with diabetes during outbreaks of influenza.

In vitro and in vivo anti-diabetic activity of Citrullus colocynthis pulpy flesh with seeds hydro-ethanolic extract

2020 ◽  
Vol 17 (2) ◽  
Author(s):  
Aymen Owais Ghauri ◽  
Saeed Ahmad ◽  
Tayyeba Rehman
Keyword(s):  
Blood Glucose ◽  
Normal Control ◽  
Ethanolic Extract ◽  
Negative Control ◽  
Antioxidant Potential ◽  
Blood Glucose Monitoring ◽  
Glucose Levels ◽  
Blood Glucose Levels

AbstractBackgroundDiabetes is the one of the leading cause of morbidity and mortality. Traditionally phytotherapy is widely being used for diabetes treatment and highly valued. Citrus colocynthis has known anti-diabetic potential. However, anti-diabetic potential of hydro-ethanolic extract of C. colocynthis pulpy flesh with seeds is not reported yet.MethodsThe extract of C. colocynthis pulpy flesh with seeds was done by maceration method using 70% ethanol. To evaluate anti-diabetic and antioxidant potential of the seeded fruit in vitro, α-glucosidase and DPPH inhibition assays was done, respectively. In vivo study used streptozotocin (STZ) induced diabetes model of rats. Rats were randomized in five groups i. e. normal control, negative control, standard control, C. colocynthis 150 and 300 mg/kg. STZ was administered to all groups except normal control. After wards, plant extract and glibenclamide is continued for 14 days. Blood samples were collected from rat tail vein daily and from Cardiac puncture at the end of study. The blood glucose levels were monitored daily by using one-touch blood glucose monitoring system. The blood glucose level was monitored on 0, 1st, 5th, 8th, 11th, and 14th day of induction.ResultsHydro-ethanolic extract of C. colocynthis pulpy flesh with seeds was able to decolorize DPPH and therefore possess antioxidant potential, continuous administration for 14 days showed a marked decrease in serum glucose levels (p 0.01) it is found to be somewhat less effective as glibenclamide (standard control) (p 0.001). A time-dependent decrease in blood glucose levels was observed (351.3 ± 4 to 258 m/kg).ConclusionHydro-ethanolic extract of C. colocynthis pulpy flesh with seeds lowered the serum triglyceride and cholesterol levels in diabetic rats significantly as compared to negative control. The hypoglycemic effect of hydro-ethanolic extract of C. colocynthis pulpy flesh with seeds is may be due to α-glucosidase inhibition potential.

scholarly journals In vivo reprogramming of pancreatic acinar cells to three islet endocrine subtypes

eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Weida Li ◽  
Mio Nakanishi ◽  
Adrian Zumsteg ◽  
Matthew Shear ◽  
Christopher Wright ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Regenerative Medicine ◽  
Acinar Cells ◽  
Pancreatic Acinar Cells ◽  
Specific Cell ◽  
Β Cells ◽  
Β Cell ◽  
Cell Induction ◽  
Direct Lineage Conversion

Direct lineage conversion of adult cells is a promising approach for regenerative medicine. A major challenge of lineage conversion is to generate specific cell subtypes. The pancreatic islets contain three major hormone-secreting endocrine subtypes: insulin+ β-cells, glucagon+ α-cells, and somatostatin+ δ-cells. We previously reported that a combination of three transcription factors, Ngn3, Mafa, and Pdx1, directly reprograms pancreatic acinar cells to β-cells. We now show that acinar cells can be converted to δ-like and α-like cells by Ngn3 and Ngn3+Mafa respectively. Thus, three major islet endocrine subtypes can be derived by acinar reprogramming. Ngn3 promotes establishment of a generic endocrine state in acinar cells, and also promotes δ-specification in the absence of other factors. δ-specification is in turn suppressed by Mafa and Pdx1 during α- and β-cell induction. These studies identify a set of defined factors whose combinatorial actions reprogram acinar cells to distinct islet endocrine subtypes in vivo.

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