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Adiponectin, a relatively recently discovered hormone produced by adipose tissue, appears to be related to our weight, inflammation and heart disease.
As obesity , diabetes and the resulting health problems increase dramatically in modern life, science has set out to discover all the mechanisms behind them. Thus, until recently we were unaware of terms such as metabolic syndrome , insulin resistance, oxidative stress , but also substances and even hormones involved in the creation of morbid patterns.
The discovery of leptin in the 1990s – the hormone produced by that most unlikely of endocrine ‘organs’, fat – turned research on adipose tissue itself. It wasn’t until 2001 that science discovered another hormone, adiponectin , produced by the same tissue and, as the evidence so far shows, plays a key role in protecting against insulin resistance, diabetes and atherosclerosis. Decreased levels of adiponectin are thought to be associated with the development of type 2 diabetes, obesity and cardiovascular disease.
What is adiponectin and how is it related to obesity?
Adiponectin is a protein consisting of 244 amino acids and is mainly secreted by the adipose tissue of the body. Women have higher levels of adiponectin than men. Adiponectin levels decrease in obesity and are associated with insulin sensitivity .
Obese people have reduced levels of adiponectin. On the other hand, adiponectin levels are higher than normal in people who are underweight , anorexic, or malnourished.
As a general rule we could say that the more body fat someone has, the lower the adiponectin levels and vice versa. Weight loss results in an increase in adiponectin levels.
What happens in insulin resistance?
But what about insulin sensitivity? Insulin is the hormone that allows muscle, fat and liver cells to absorb glucose found in the blood. Glucose serves as energy in specific cells or is converted into fat for later use by the body. But insulin also affects other metabolic processes, such as the breakdown of fat or proteins.
Insulin resistance occurs when cells do not respond to insulin as they should, resulting in too much insulin being released into the blood (hyperinsulinemia). Insulin resistance can lead to prediabetes , type 2 diabetes and gestational diabetes . But how is insulin resistance linked to adiponectin? People with insulin resistance usually have low levels of adiponectin . Thus, its low levels are a predictor of the development of insulin resistance.
The relationship of adiponectin to insulin
The interesting thing here is that while insulin resistance is often associated with obesity, people can have it without being obese. But beware, people who have insulin resistance without being obese also usually have low levels of adiponectin. When adiponectin levels are low, insulin has a reduced ability to do its job.
This suggests that there may be a genetic factor involved in insulin resistance and adiponectin. Also, that the role of adiponectin is probably more important than that of insulin for the functioning of the metabolism and the maintenance of the body’s homeostasis. Adiponectin secretion is increased by insulin and its main role is to regulate glucose production and catabolize fatty acids.
But since people with severe lipodystrophy (a syndrome that causes a lack of fat tissue in certain parts of the body) also have low adiponectin, we understand that this hormone plays a role in how the body stores fat .
