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Differentiated Mouse Adipocytes in Primary Culture: A Model of Insulin Resistance
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Insulin Resistance, Obesity, and Lipotoxicity

Dilek Yazıcı1, Selin Çakmak Demir2, Havva Sezer2

  • 1Koç University Medical School, Section of Endocrinology and Metabolism, Koç University Hospital, Topkapi, Istanbul, Turkey. dyazici@ku.edu.tr.

Advances in Experimental Medicine and Biology
|September 17, 2024
PubMed

Insights

Lipotoxicity, or excess fat accumulation, impairs metabolic pathways and causes organ dysfunction. This condition is a key factor in insulin resistance and increased cardiometabolic risk.

Area of Science:

  • Metabolic and Cardiovascular Science
  • Endocrinology
  • Pathophysiology

Background:

  • Lipotoxicity, characterized by excess fat accumulation, disrupts glucose metabolism and causes functional impairments in adipose tissue and peripheral organs including the liver, heart, pancreas, and muscle.
  • Ectopic lipid accumulation in organs like the kidneys, liver, and heart is linked to clinical conditions such as diabetic nephropathy, nonalcoholic fatty liver disease, and cardiomyopathy.
  • Lipotoxicity contributes to insulin resistance, pancreatic beta-cell dysfunction, and reproductive disorders like polycystic ovary syndrome.

Purpose of the Study:

  • To elucidate the multifaceted role of lipotoxicity in metabolic dysfunction.
  • To explore the mechanisms linking lipotoxicity to insulin resistance in non-adipose tissues.
  • To understand the contribution of lipotoxicity to overall cardiometabolic risk.

Main Methods:

  • Review of existing literature on lipotoxicity and its effects on metabolic pathways.
  • Analysis of cellular and molecular mechanisms, including protein kinase C and JNK-1 pathways.
  • Examination of the roles of mitochondrial dysfunction and endoplasmic reticulum stress in lipotoxicity-induced insulin resistance.

Main Results:

  • Lipotoxicity impairs metabolic pathways in adipose tissue and peripheral organs, leading to ectopic lipid accumulation and associated diseases.
  • Insulin resistance in muscle and liver is linked to increased circulating lipids and altered fatty acid metabolism.
  • Specific pathways (PKC, JNK-1), mitochondrial dysfunction, and endoplasmic reticulum stress are implicated in lipotoxicity-driven insulin resistance.

Conclusions:

  • Lipotoxicity is a central mechanism underlying insulin resistance and pancreatic beta-cell dysfunction.
  • Ectopic lipid accumulation contributes to significant organ damage and clinical pathologies.
  • Lipotoxicity plays a critical role in the increased cardiometabolic risk associated with visceral adiposity and insulin resistance.
Keywords:
CardiomyopathyCeramidesCytokinesDiabetic nephropathyDiacylglycerolEndoplasmic reticulum stressFatty acidsInsulin resistanceLipotoxicityNonalcoholic fatty liver diseaseObesityPolycystic ovary syndromeType 2 diabetes mellitus

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