conclude and rewrite the following answer in less words :

The pathophysiology of diabetes mellitus involves the following key components:

Insulin secretion and action: Insulin is a hormone secreted by the pancreas that enables cells to absorb glucose from the bloodstream and use it for energy production or storage. In diabetes mellitus, either the pancreas does not produce enough insulin $($type $1$ diabetes$)$ or the body's cells become resistant to insulin's effects $($type $2$ diabetes$).$

Glucose metabolism: In a healthy individual, when blood glucose levels rise after a meal, the pancreas secretes insulin, which promotes glucose uptake by cells, particularly in the liver, muscle, and adipose tissue. This reduces blood glucose levels. In diabetes mellitus, due to insulin deficiency or resistance, glucose uptake is impaired, leading to high blood glucose levels.

Counter$-$regulatory hormones: In response to low blood glucose levels, the body secretes counter$-$regulatory hormones such as glucagon, cortisol, epinephrine, and growth hormone. These hormones increase blood glucose levels by promoting glucose production in the liver and reducing glucose uptake by cells. In diabetes mellitus, due to insulin deficiency or resistance, the counter$-$regulatory hormones' effects are exaggerated, further exacerbating high blood glucose levels.