Effects of liraglutide on intrapancreatic fat deposition in patients with type 2 diabetes

Association between intra-pancreatic fat deposition and diseases of the exocrine pancreas: A narrative review

Intrapancreatic fat deposition (IPFD) has garnered increasing attention in recent years. The prevalence of IPFD is relatively high and associated with factors such as obesity, age, and sex. However, the pathophysiological mechanisms underlying IPFD remain unclear, with several potential contributing factors, including oxidative stress, alterations in the gut microbiota, and hormonal imbalances. IPFD was found to be highly correlated with the occurrence and prognosis of exocrine pancreatic diseases. Although imaging techniques remain the primary diagnostic approach for IPFD, an expanding array of biomarkers and clinical scoring systems have been identified for screening purposes. Currently, effective treatments for IPFD are not available; however, existing medications, such as glucagon-like peptide-1 receptor agonists, and new therapeutic approaches explored in animal models have shown considerable potential for managing this disease. This paper reviews the pathogenesis of IPFD, its association with exocrine pancreatic diseases, and recent advancements in its diagnosis and treatment, emphasizing the significant clinical relevance of IPFD.

Effects of liraglutide on abdominal fat distribution and glucose metabolism in Chinese subjects with obesity

AIMS

To observe the effects of liraglutide on abdominal fat distribution in Chinese subjects with obesity in 12 weeks, and further to explore the correlation between abdominal fat content and glucose metabolism after monotherapy.

METHODS

This study recruited 71 obese subjects. All the subjects have received liraglutide monotherapy (0.6 mg-1.8 mg/d) for 12 weeks. Clinical assessment, laboratory assays and magnetic resonance imaging (MRI) examination were accessed at baseline and after 12 weeks treatment. MRI was applied to measure abdominal fat distribution, calculated by proton-density fat fraction (PDFF).

RESULTS

After 12 weeks of liraglutide monotherapy, body weight in the obese participants decreased significantly (P < 0.001). Fasting blood glucose (FBG) levels, 2 h post-load blood glucose (2hPBG) levels, and glycosylated hemoglobin (HbA1c) were remarkably improved after liraglutide monotherapy (all P < 0.001). Subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) were significantly reduced after liraglutide monotheraphy (both P < 0.001). There was a notable reduction in liver fat content (LFC) after liraglutide monotherapy (P < 0.001). In the further analysis, LFC was greater in obese subjects with impaired glucose regulation (IGR) at baseline compared to those with normal glucose tolerance (NGT) (P = 0.002). The LFC reduction in IGR group was significantly greater than those in NGT group after liraglutide treatment (P < 0.001). Pearson correlation analysis showed that reduction of LFC was significantly correlated with improvement of FBG (r = 0.587, P < 0.001) and HbA1c (r = 0.607, P < 0.001) in obese patients.

CONCLUSION

LFC was significantly reduced after liraglutide monotherapy for 12 weeks in subjects with obesity. The LFC reduction is likely to be associated with IGR remission in obese subjects.

The Causal Role of Ectopic Fat Deposition in the Pathogenesis of Metabolic Syndrome

Consuming a "modern" Western diet and overnutrition may increase insulin secretion. Additionally, nutrition-mediated hyperinsulinemia is a major driver of ectopic fat deposition. The global prevalence of metabolic syndrome is high and growing. Within this context, people with congenital lipodystrophy often experience a severe form of metabolic syndrome. Evidence is increasingly supporting that subtle partial lipodystrophy plays an important role in the development of metabolic syndrome in the general population. In individuals in the general population with subtle partial lipodystrophy, as well as in those with congenital lipodystrophy, the subcutaneous adipose tissues are unable to accommodate surplus energy intake. In both conditions, (excess) fat is directed toward the liver, pancreas, and muscles, where it is deposited as ectopic fat, as this fat can no longer be stored in the "safe" subcutaneous fat depots. Ectopic fat depositions cause insulin resistance in the liver and muscles, as well as β-cell dysfunction in the pancreas. Support of a direct pathological role of ectopic fat deposition in this condition is further provided by the rapid normalization of hepatic insulin sensitivity and improvement in pancreatic β-cell function after marked reductions in ectopic fat depositions. Thus, ectopic fat deposition in the liver, pancreas, and muscles may play a causal role in the pathogenesis of metabolic syndrome even in the general population. As such, the prevention of ectopic fat deposition may reduce the risk of metabolic syndrome and mitigate its effects.

Correlation between type 2 diabetes mellitus remission and intrapancreatic fat deposition

BACKGROUND

Intrapancreatic fat deposition (IPFD) exerts a significant negative impact on patients with type 2 diabetes mellitus (T2DM), accelerates disease deterioration, and may lead to impaired β-cell quality and function.

AIM

To investigate the correlation between T2DM remission and IPFD.

METHODS

We enrolled 80 abdominally obese patients with T2DM admitted to our institution from January 2019 to October 2023, including 40 patients with weight loss-induced T2DM remission (research group) and 40 patients with short-term intensive insulin therapy-induced T2DM remission (control group). We comparatively analyzed improvements in IPFD [differential computed tomography (CT) values of the spleen and pancreas and average CT value of the pancreas]; levels of fasting blood glucose (FBG), 2-h postprandial blood glucose (2hPBG), and insulin; and homeostasis model assessment of insulin resistance (HOMA-IR) scores. Correlation analysis was performed to explore the association between T2DM remission and IPFD.

RESULTS

After treatment, the differential CT values of the spleen and pancreas, FBG, 2hPBG, and HOMA-IR in the research group were significantly lower than those before treatment and in the control group, and the average CT value of the pancreas and insulin levels were significantly higher. Correlation analysis revealed that the greater the T2DM remission, the lower the amount of IPFD.

CONCLUSION

T2DM remission and IPFD are inversely correlated.

The Pharmacological Landscape for Fatty Change of the Pancreas

The quest for medications to reduce intra-pancreatic fat deposition is now quarter a century old. While no specific medication has been approved for the treatment of fatty change of the pancreas, drug repurposing shows promise in reducing the burden of the most common disorder of the pancreas. This leading article outlines the 12 classes of medications that have been investigated to date with a view to reducing intra-pancreatic fat deposition. Information is presented hierarchically-from preclinical studies to retrospective findings in humans to prospective interventional studies to randomised controlled trials. This lays the grounds for shepherding the most propitious drugs into medical practice through well-designed basic science studies and adequately powered randomised controlled trials.