Question 1

What is the Meaning of Dipeptidyl Peptidase IV (DPP-4)?

Accepted Answer

Dipeptidyl Peptidase IV (DPP-4) is an enzyme found on cell surfaces, crucial for glucose metabolism by deactivating specific peptide hormones. This serine protease cleaves dipeptides from polypeptide N-termini, preferring substrates with proline or alanine at the penultimate position. Its widespread presence underscores broad physiological involvement.

Question 2

What is the Context of Dipeptidyl Peptidase IV (DPP-4)?

Accepted Answer

Within the endocrine system, DPP-4 primarily acts on incretin hormones, notably glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). These gut-derived hormones, secreted post-nutrient intake, stimulate insulin release and suppress glucagon, lowering blood glucose. DPP-4 rapidly degrades these incretins, limiting their physiological duration.

Question 3

What is the Significance of Dipeptidyl Peptidase IV (DPP-4)?

Accepted Answer

The clinical significance of DPP-4 lies in its role as a therapeutic target for type 2 diabetes. Inhibiting this enzyme reduces endogenous GLP-1 and GIP degradation, sustaining incretin levels. This enhances glucose-dependent insulin secretion and suppresses glucagon, improving glycemic control. Its inhibition offers a targeted approach to managing hyperglycemia.

Question 4

What is the Mechanism of Dipeptidyl Peptidase IV (DPP-4)?

Accepted Answer

DPP-4 functions by cleaving the N-terminal dipeptide from active incretin hormones like GLP-1 and GIP, rendering them inactive. This enzymatic action terminates their signaling at pancreatic beta and alpha cell receptors. Inhibition allows active GLP-1 and GIP to persist longer, leading to enhanced glucose-stimulated insulin secretion and reduced hepatic glucose production.

Question 5

What is the Application of Dipeptidyl Peptidase IV (DPP-4)?

Accepted Answer

In clinical practice, DPP-4 inhibitors (gliptins) are widely prescribed oral medications for type 2 diabetes. Examples include sitagliptin and linagliptin, often used alone or in combination. Their application aims to improve glycemic parameters without typically causing weight gain or significant hypoglycemia risk, making them a valuable patient option.

Question 6

What is the Metric of Dipeptidyl Peptidase IV (DPP-4)?

Accepted Answer

The effectiveness of DPP-4 inhibition in type 2 diabetes is monitored through standard glycemic control metrics. These include fasting plasma glucose, postprandial glucose levels, and crucially, glycated hemoglobin (HbA1c). While DPP-4 enzyme activity is not routinely measured, its therapeutic impact is directly reflected in these glucose-related biomarkers, indicating improved metabolic regulation.

Question 7

What is the Risk of Dipeptidyl Peptidase IV (DPP-4)?

Accepted Answer

While generally well-tolerated, DPP-4 inhibitors carry potential risks. These include nasopharyngitis, upper respiratory tract infections, and headaches. Rare but serious adverse events, such as pancreatitis, severe allergic reactions, and arthralgia, have been reported. Patients with pancreatitis or heart failure history require careful evaluation; their use should always be under medical supervision for patient safety.

Dipeptidyl Peptidase IV (DPP-4)

Meaning

Context

Significance

Mechanism

Application

Metric

Risk

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