Insulin Actions and Diabetes Metabolism

Actions of Insulin in Metabolic Processes

• Insulin binds to receptors in various tissues, triggering metabolic actions.
• In muscle tissue, insulin facilitates glucose uptake, stimulates amino acid uptake, promotes protein synthesis, and prevents protein breakdown.
• In adipose tissue, insulin stimulates fatty acid and triglyceride synthesis while preventing lipolysis.
• In liver and muscle, insulin increases glycogen synthesis and inhibits glycogenolysis.
• In the liver, insulin also promotes fatty acid synthesis and prevents gluconeogenesis.
• Insulin is primarily an anabolic hormone promoting storage and synthesis of nutrients.

Diabetes Mellitus Overview

• Diabetes mellitus is a group of metabolic diseases characterized by defects in insulin secretion or action.
• Common outcome of diabetes is hyperglycemia, due to glucose transporters being inactive or absent in cell membranes.
• Persistent high blood glucose can cause long-term damage to body tissues.

Etiologic Classification of Diabetes Mellitus

• Type 1 diabetes is often not diagnosed until there is significant hyperglycemia, as many individuals initially exhibit normal blood sugar levels.
• Environmental triggers, like infections, may provoke an autoimmune response against β-cells, leading to antibody production.
• Early screening for risk factors should include family history and may reveal pre-diabetes years before full-blown diabetes develops.
• Insulin is the primary treatment for Type 1 diabetes; accurate diagnosis is necessary before initiating lifelong insulin therapy.

Clinical Features and Complications

• Women with polycystic ovary syndrome (PCOS) may show elevated serum testosterone levels and require careful management regarding diabetes risk.
• Psychotropic drugs are linked to increased insulin resistance and blood sugar levels.
• Major heart attack risk factors include elevated waist circumference and waist-hip ratio.
• Complications of diabetes can be acute (e.g., diabetic ketoacidosis) or chronic (e.g., vascular diseases) and result from prolonged hyperglycemia.

Factors Promoting Diabetes Complications

• Complications arise not solely from hyperglycemia, but also associated conditions like hypertension and dyslipidemia.
• Treatment should address not only blood sugar management but also correction of contributing factors shaping the patient’s overall health.

Targeted Treatment Options

• Treatment strategies may depend on the site of pathology (liver, muscle, adipose, or pancreas).
• Metformin or thiazolidinediones (like Pioglitazone) are used for liver issues; thiazolidinediones are preferred for muscle/adipose abnormalities.
• SGLT-2 inhibitors can be beneficial for kidney-related issues.
• In cases related to pancreatic function, use of insulin, incretins, or GLP-1 receptor agonists is indicated.
• Availability of certain medications may vary by region, affecting treatment options in the Philippines.

This quiz explores the metabolic processes influenced by insulin and its role in diabetes mellitus. It focuses on insulin secretion defects and how they impact various metabolic pathways. Understand the nuances of insulin's actions and its significance in maintaining metabolic balance.