A new phase of insulin secretion. How will it contribute to our understanding of beta-cell function?

Extra virgin olive oil (EVOO) is a major component of the Mediterranean diet and is appreciated worldwide because of its nutritional benefits in metabolic diseases, including type 2 diabetes (T2D). EVOO contains significant amounts of secondary metabolites, such as phenolic compounds (PCs), that may positively influence the metabolic status. In this study, we investigated for the first time the effects of several PCs on beta-cell function and survival. To this aim, INS-1E cells were exposed to 10 μM of the main EVOO PCs for up to 24 h. Under these conditions, survival, insulin biosynthesis, glucose-stimulated insulin secretion (GSIS), and intracellular signaling activation (protein kinase B (AKT) and cAMP response element-binding protein (CREB)) were evaluated. Hydroxytyrosol, tyrosol, and apigenin augmented beta-cell proliferation and insulin biosynthesis, and apigenin and luteolin enhanced the GSIS. Conversely, vanillic acid and vanillin were pro-apoptotic for beta-cells, even if they increased the GSIS. In addition, oleuropein, p-coumaric, ferulic and sinapic acids significantly worsened the GSIS. Finally, a mixture of hydroxytyrosol, tyrosol, and apigenin promoted the GSIS in human pancreatic islets. Apigenin was the most effective compound and was also able to activate beneficial intracellular signaling. In conclusion, this study shows that hydroxytyrosol, tyrosol, and apigenin foster beta-cells’ health, suggesting that EVOO or supplements enriched with these compounds may improve insulin secretion and promote glycemic control in T2D patients.

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Glycemia, Beta-Cell Function and Sensitivity to Insulin in Mildly to Critically Ill Covid-19 Patients

Medicina ◽

10.3390/medicina57010068 ◽

2021 ◽

Vol 57 (1) ◽

pp. 68 ◽

Cited By ~ 1

Author(s):

Ioannis Ilias ◽

Aristidis Diamantopoulos ◽

Maria Pratikaki ◽

Efthymia Botoula ◽

Edison Jahaj ◽

...

Keyword(s):

Insulin Secretion ◽

Beta Cell ◽

Critically Ill ◽

Beta Cell Function ◽

Cell Function ◽

Model Assessment ◽

Secondary Diabetes ◽

C Peptide ◽

Number Of Patients ◽

Patients With Diabetes

Background and objectives: Critically and non-critically ill patients with SARS-CoV-2 infection (Covid-19) may present with higher-than-expected glycemia, even in the absence of diabetes. With this study we aimed to assess glucose, glycemic gap (GlyG) and insulin secretion/sensitivity measures in patients with Covid-19. Materials and Methods: We studied, upon admission, 157 patients with Covid-19 (84: in wards and 73: in intensive care units; ICU); 135 had no history of diabetes. We measured blood glucose upon admission as well as glycated hemoglobin (A1c), plasma insulin and C-peptide. We calculated the GlyG and the Homeostasis Model Assessment 2 (HOMA2) estimates of steady state beta cell function (HOMA2%B) and insulin sensitivity (HOMA2%S). Statistical assessment was done with analysis or the Kruskal-Wallis test. Results: Compared to patients in the wards without diabetes, patients with diabetes in the wards, as well as patients in the ICU (without or with diabetes) had higher admission glycemia. The GlyG was significantly higher in patients without diabetes in the ICU compared to patients without diabetes in the wards, while HOMA2%B based on glucose and insulin was significantly higher in the ICU patients compared to patients in the wards. Of all the parameters, HOMA2%S based on C-peptide/glucose was higher in survivors (n = 133). Conclusions: In our series of patients with Covid-19, a substantial number of patients with and without diabetes had admission hyperglycemia and those who were critically ill may have had compromised insulin secretion and lowered sensitivity to insulin. These findings lend credence to reports of association between Covid-19 and hyperglycemia/secondary diabetes.

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Pancreatic beta-cell function and glucose metabolism in human segmental pancreas and kidney transplantation

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.1993.264.3.e441 ◽

1993 ◽

Vol 264 (3) ◽

pp. E441-E449 ◽

Cited By ~ 2

Author(s):

E. Christiansen ◽

H. B. Andersen ◽

K. Rasmussen ◽

N. J. Christensen ◽

K. Olgaard ◽

...

Keyword(s):

Insulin Secretion ◽

Glucose Metabolism ◽

Beta Cell ◽

Kidney Transplant ◽

Beta Cell Function ◽

Cell Function ◽

Pancreatic Beta Cell ◽

Secretion Rate ◽

C Peptide ◽

Insulin Secretion Rate

beta-Cell function and glucose metabolism were studied in eight insulin-dependent diabetic recipients of combined segmental pancreas and kidney transplant with peripheral insulin delivery (Px), in eight nondiabetic kidney-transplant individuals (Kx), and in eight normal subjects (Ns) after three consecutive mixed meals. All subjects had normal fasting plasma glucose, but increased basal levels of C-peptide were demonstrated in the transplant groups (P < 0.05 relative to Ns). Postprandial hyperglycemia was increased 14% in Kx and 32% in Px (P < 0.05), whereas compared with Ns postprandial C-peptide levels were increased three- and twofold, respectively, in Kx and Px (P < 0.05). Compared with Ns basal insulin secretion rate (combined model) was increased 2-fold in Kx and 1.4-fold in Px (P < 0.05). Maximal insulin secretion rate was reduced 25% in Px compared with Kx (P < 0.05) but not different from that of Ns (P NS). Also, maximal insulin secretion rate occurred later in Px than in controls (Tmax: Px 50 min, Kx 30 min, and Ns 32 min; P < 0.05). The total integrated insulin secretion was increased 1.4-fold in Px compared with Ns (P < 0.05) but decreased 1.4-fold compared with Kx (P < 0.05). Fasting and postprandial proinsulin-to-C-peptide molar ratios were inappropriately increased in Px compared with Kx and Ns. Basal hepatic glucose production was increased 43% in Px and 33% in Kx compared with Ns (P < 0.05). Postprandial total systemic glucose appearance was similar in all three groups, whereas peripheral glucose disposal was 15% reduced in Px (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

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The zinc transporter Zip14 (SLC39a14) affects Beta-cell Function: Proteomics, Gene expression, and Insulin secretion studies in INS-1E cells

Scientific Reports ◽

10.1038/s41598-019-44954-1 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

Trine Maxel ◽

Kamille Smidt ◽

Charlotte C. Petersen ◽

Bent Honoré ◽

Anne K. Christensen ◽

...

Keyword(s):

Gene Expression ◽

Insulin Secretion ◽

Beta Cell ◽

Beta Cell Function ◽

Cell Function ◽

Zinc Transporter

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Clinical Significance of the Maximum Body Mass Index Before Onset of Type 2 Diabetes for Predicting Beta-Cell Function

Journal of the Endocrine Society ◽

10.1210/jendso/bvz023 ◽

2020 ◽

Vol 4 (4) ◽

Author(s):

Harutoshi Ozawa ◽

Kenji Fukui ◽

Sho Komukai ◽

Yoshiya Hosokawa ◽

Yukari Fujita ◽

...

Keyword(s):

Type 2 Diabetes ◽

Body Mass Index ◽

Insulin Secretion ◽

Beta Cell ◽

Clinical Significance ◽

Beta Cell Function ◽

Cell Function ◽

Duration Of Diabetes ◽

Maximum Body

Abstract Objective This study aimed to clarify the clinical significance of the maximum body mass index (BMI) before the onset of type 2 diabetes (MBBO) for predicting pancreatic beta-cell function. Methods This was a cross-sectional observational study. Of 1304 consecutively admitted patients with type 2 diabetes, we enrolled 410 patients satisfying the criteria in this study. The correlations between the C-peptide index (CPI), which is one of the parameters that reflects beta-cell function, and various clinical parameters, including MBBO and duration of diabetes, were analyzed in multiple linear regression analyses. Results The analyses revealed that MBBO was correlated with CPI independently after adjustment for age, sex, HbA1c, and duration of diabetes. When we divided the subjects into three subgroups by MBBO (MBBO < 25 kg/m2; 25 kg/m2 ≤ MBBO < 30 kg/m2; MBBO ≥ 30 kg/m2), CPI was negatively correlated with duration of diabetes in each subgroup, while the rates of CPI based on the duration of diabetes were not different among the three MBBO subgroups. In contrast, the declining rates of CPI were higher in the BMI ≥ 25 kg/m2 group on admission than in the BMI < 25 kg/m2 group on admission. Conclusions MBBO may be an independent factor correlating with beta-cell function and may predict insulin secretion capacity at diagnosis, but it does not seem to affect the rate of decline in insulin secretion capacity after diagnosis. It is important to preserve beta-cell function by decreasing a patient’s BMI during treatment after diagnosis regardless of MBBO.

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1,25-Dihydroxyvitamin D3 and pancreatic beta-cell function: vitamin D receptors, gene expression, and insulin secretion.

Endocrinology ◽

10.1210/endo.134.4.8137721 ◽

1994 ◽

Vol 134 (4) ◽

pp. 1602-1610 ◽

Cited By ~ 93

Author(s):

S Lee ◽

S A Clark ◽

R K Gill ◽

S Christakos

Keyword(s):

Gene Expression ◽

Vitamin D ◽

Insulin Secretion ◽

Beta Cell ◽

Beta Cell Function ◽

Cell Function ◽

Pancreatic Beta Cell ◽

Dihydroxyvitamin D3 ◽

Vitamin D Receptors ◽

Pancreatic Beta Cell Function

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A Systematic Review of Beta Cell Function in Adults of Black African Ethnicity

Journal of Diabetes Research ◽

10.1155/2019/7891359 ◽

2019 ◽

Vol 2019 ◽

pp. 1-17 ◽

Cited By ~ 1

Author(s):

M. Ladwa ◽

O. Hakim ◽

S. A. Amiel ◽

L. M. Goff

Keyword(s):

Insulin Secretion ◽

Glucose Tolerance ◽

Beta Cell ◽

Beta Cell Function ◽

Cell Function ◽

Normal Glucose Tolerance ◽

Qualitative Synthesis ◽

Intravenous Glucose ◽

Black African

Background. Understanding ethnic differences in beta cell function has important implications for preventative and therapeutic strategies in populations at high risk of type 2 diabetes (T2D). The existing literature, largely drawn from work in children and adolescents, suggests that beta cell function in black African (BA) populations is upregulated when compared to white Europeans (WE). Methods. A systematic literature search was undertaken in June 2018 to identify comparative studies of beta cell function between adults (>age 18 years) of indigenous/diasporic BA and WE ethnicity. All categories of glucose tolerance and all methodologies of assessing beta cell function in vivo were included. Results. 41 studies were identified for inclusion into a qualitative synthesis. The majority were studies in African American populations (n=30) with normal glucose tolerance (NGT)/nondiabetes (n=25), using intravenous glucose stimulation techniques (n=27). There were fewer studies in populations defined as only impaired fasting glucose/impaired glucose tolerance (IFG/IGT) (n=3) or only T2D (n=3). Although BA broadly exhibited greater peripheral insulin responses than WE, the relatively small number of studies which measured C-peptide to differentiate between beta cell insulin secretion and hepatic insulin extraction (n=14) had highly variable findings. In exclusively IGT or T2D cohorts, beta cell insulin secretion was found to be lower in BA compared to WE. Conclusions. There is inconsistent evidence for upregulated beta cell function in BA adults, and they may in fact exhibit greater deficits in insulin secretory function as glucose intolerance develops.

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