Effect of liraglutide on lipids in patients with type 2 diabetes: a pilot study

The Possible Effect of the Long-Term Use of Glucagon-like Peptide-1 Receptor Agonists (GLP-1RA) on Hba1c and Lipid Profile in Type 2 Diabetes Mellitus: A Retrospective Study in KAUH, Jeddah, Saudi Arabia

(1) Background: Type 2 diabetes (T2DM) is a chronic metabolic disease with serious health complications. T2DM is associated with many chronic illnesses, including kidney failure, cardiovascular diseases (CVD), vision loss, and other related diseases. Obesity is one of the major factors associated with insulin resistance and dyslipidemia. Recently, the development of GLP-1 Receptor agonist (GLP-1RA) showed great therapeutic potential for T2DM. Aim: To retrospectively investigate the association of the long-term use of GLP-1RA therapy in T2DM patients with HbA1c levels and dyslipidemia. (2) Methods: Retrospective data collection and analysis of demographic, clinical records, and biochemical parameters were carried out for 72 T2DM taking GLP-1RA treatments for six months. (3) Results: A total of 72 T2DM patients with a mean age = 55 (28 male and 44 female) were divided into two groups. Group 1 received statins (n = 63), and group 2 did not receive statins (n = 9). The GLP-1RA effect on BMI was significantly decreased in group 1 (p < 0.01). A significant effect was observed for HbA1c in both groups for six months of treatment duration (p < 0.05). The AST levels significantly decreased in group 2 from 25.2 to 19.4 U\L (p = 0.011). (4) Conclusions: GLP-1RA treatments were associated with weight reduction and improved glycemic control for T2DM patients. Moreover, it is suggested that it has anti-inflammatory and hepatoprotective effects. However, no direct association was found with the lipid profile in all groups of T2DM.

Exenatide prevents statin-related LDL receptor increase and improves insulin secretion in pancreatic beta cells (1.1E7) in a protein kinase A-dependent manner

Statins are primary drugs in the treatment of hyperlipidemias. This group of drugs is known for its beneficial pleiotropic effects (e.g., reduction of inflammatory state). However, a growing body of evidence suggests its diabetogenic properties. The culpable mechanism is not completely understood and might be related to the damage to pancreatic beta cells. Therefore, we conceived an in vitro study to explore the impact of atorvastatin on pancreatic islet beta cells line (1.1.E7). We evaluated the influence on viability, insulin, low-density lipoprotein (LDL) receptor, and proprotein convertase subtilisin/kexin type 9 (PCSK9) expression. A significant drop in mRNA for proinsulin and insulin expression was noted. Concurrently, a rise in LDL receptor at the protein level in cells exposed to atorvastatin was noted. Further experiments have shown that exenatide - belonging to glucagon-like peptide 1 (GLP-1) analogs that are used in a treatment of diabetes and known for its weight reducing properties - can alleviate the observed alterations. In this case, the mechanism of action of exenatide was dependent on a protein kinase A pathway. In conclusion, our results support the hypothesis that statin may have diabetogenic properties, which according to our study is related to reduced insulin expression. The concomitant use of GLP-1 receptor agonist seemed to successfully revert insulin expression.

Exenatide improves antioxidant capacity and reduces the expression of LDL receptors and PCSK9 in human insulin-secreting 1.1E7 cell line subjected to hyperglycemia and oxidative stress

Introduction

GLP-1 receptor agonists (e.g., exenatide) are novel drugs used in the treatment of diabetes. These drugs, working with other mechanisms of action, improve glycemic control by increasing secretion of insulin and improving survival of pancreatic islet beta cells. Alterations in the oxidative stress level or the expression of proteins associated with cholesterol uptake might be responsible for those findings. Currently, there are few in vitro studies on the impact of exenatide antioxidant capacity in human islet beta cell lines and none that assess the influence of exenatide on LDL receptors and PCSK9 under hyperglycemia and oxidative stress. Therefore, we evaluated the impact of exenatide on antioxidant capacity, insulin secretion, and proteins involved in cholesterol metabolism.

Materials and Method

An in vitro culture of insulin-secreting cells 1.1E7 was subjected to hyperglycemia and oxidative stress. Assessment was made of the expression of enzymes associated with oxidative stress (NADPH oxidase, catalase, glutathione peroxidase, superoxide dismutase, iNOS) and cholesterol uptake (LDL receptors, PCSK9). Additionally, insulin and nitrite levels in culture media were quantified.

Results

We showed that exenatide improves expression of catalase and reduces the amount of nitrite in cell cultures in a protein kinase A–dependent manner. Those results were accompanied by a drop in the expression of LDL receptors and PCSK9. Insulin secretion was modestly increased in the culture condition.

Conclusions

Our findings show potential protective mechanisms exerted by exenatide in human insulin-secreting pancreatic beta cell line (1.1E7), which may be exerted through increased antioxidant capacity and reduced accumulation of cholesterol.

GLP-1 Receptor Agonist Effects on Lipid and Liver Profiles in Patients with Nonalcoholic Fatty Liver Disease: Systematic Review and Meta-Analysis

AIMS

This meta-analysis of randomized placebo-controlled clinical trials assessed the effect of glucose-like peptide-1-receptor agonists (GLP-1RA) on the lipid profile and liver enzymes in patients with nonalcoholic fatty liver disease (NAFLD).

MATERIALS AND METHODS

Randomized placebo-controlled trials investigating GLP-1RA on the lipid profile and liver enzymes in patients with NAFLD were searched in PubMed-Medline, Scopus, Web of Science, and Google Scholar databases (from inception to January 2020). A random-effects model and a generic inverse variance method were used for quantitative data synthesis. Sensitivity analysis was conducted. Weighted random-effects meta-regression was performed on potential confounders on lipid profile and liver enzyme concentrations.

RESULTS

12 studies were identified (12 GLP-1RA arms; 677 subjects) that showed treatment with GLP-1RA reduced alanine transaminase (ALT) concentrations (WMD = -10.14, 95%CI = [-15.84, -0.44], P < 0.001), gamma-glutamyl transferase (GGT) (WMD = -11.53, 95%CI = [-15.21,-7.85], P < 0.001), and alaline phosphatase (ALP) (WMD = -8.29, 95%CI = [-11.34, -5.24], P < 0.001). Aspartate aminotransferase (AST) (WMD = -2.95, 95% CI = [-7.26, 1.37], P=0.18) was unchanged. GLP-1 therapy did not alter triglycerides (TC) (WMD = -7.07, 95%CI = [-17.51, 3.37], P=0.18), total cholesterol (TC) (WMD = -1.17 (-5.25, 2.91), P=0.57), high-density lipoprotein (HDL-C) (WMD = 0.97, 95%CI = [-1.63, 3.58], P=0.46), or low-density lipoprotein (LDL-C) (WMD = -1.67, 95%CI = [-10.08, 6.74], P=0.69) in comparison with controls.

CONCLUSION

The results of this meta-analysis suggest that GLP-1RA treatment significantly reduces liver enzymes in patients with NAFLD, but the lipid profile is unaffected.

Sodium Glucose Transporter, Type 2 (SGLT2) Inhibitors (SGLT2i) and Glucagon-Like Peptide 1-Receptor Agonists: Newer Therapies in Whole-Body Glucose Stabilization

Diabetes is a worldwide epidemic that is increasing rapidly to become the seventh leading cause of death in the world. The increased incidence of this disease mirrors a similar uptick in obesity and metabolic syndrome, and, collectively, these conditions can cause deleterious effects on a number of organ systems including the renal and cardiovascular systems. Historically, treatment of type 2 diabetes has focused on decreasing hyperglycemia and glycated hemoglobin levels. However, it now is appreciated that there is more to the puzzle. Emerging evidence has indicated that newer classes of diabetes drugs, sodium-glucose co-transporter 2 inhibitors and glucagon-like peptide 1-receptor agonists, improve cardiovascular and renal function, while appropriately managing hyperglycemia. In this review, we highlight the recent clinical and preclinical studies that have shed light on sodium-glucose co-transporter 2 inhibitors and glucagon-like peptide 1-receptor agonists and their ability to stabilize blood glucose levels while offering whole-body protection in diabetic and nondiabetic patient populations.

The Effect of Liraglutide on Epicardial Adipose Tissue in Type 2 Diabetes

OBJECTIVE

To study the effect of liraglutide on the thickness of epicardial adipose tissue (EAT) in type 2 diabetes mellitus (T2DM) patients with abdominal obesity.

METHODS

Abdominal obesity T2DM patients with poor glycemic control were collected and treated with liraglutide. The changes of blood glucose, blood lipid, waist circumference, body mass index (BMI), and EAT thickness were compared after 3 months of treatment with liraglutide. Cardiac magnetic resonance imaging (MRI) was used to measure EAT thickness.

RESULTS

After 3 months of treatment with liraglutide, glycosylated hemoglobin (HbA_1c) decreased from 9.81 ± 1.46% to 6.94 ± 1.29% (95%CI = 2.14-3.59, p < 0.001). The weight decreased from 91.67 ± 16.29 kg to 87.29 ± 16.43 kg (95%CI = 2.97-5.79, p < 0.001). Waist circumference before treatment was 103.69 ± 9.14 cm, and after treatment was 96.42 ± 8.42 cm (95%CI = 5.04-9.50, p < 0.001). Total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) were significantly lower than those before treatment. TC decreased from 5.34 ± 1.05 mmol/L to 4.86 ± 0.97 mmol/L (95%CI = 0.15-0.82, p < 0.001). TG was 1.89 (1.48-3.17) and then to 1.92 ± 0.69 (p = 0.03). LDL-C decreased from 3.39 ± 0.84 mmol/L to 3.01 ± 0.74 mmol/L (95%CI = 0.17-0.59, p = 0.001). HDL-C increased by 1.7% after treatment, with no significant difference (p = 0.062). More importantly, the thickness of EAT decreased from 5.0 (5.0-7.0) mm to 3.95 ± 1.43 mm (p < 0.001) after liraglutide administered for 3 months.

CONCLUSION

Liraglutide significantly reduces EAT thickness in T2DM with abdominal obesity, which provides theoretical support for the cardiovascular benefits of liraglutide.