Most type 2 meds work by increasing insulin production in one way or another. The extra insulin lowers blood sugar by ushering it out of your bloodstream and into your cells, where it may, unfortunately, make you fat. Wouldn’t it be nice if instead, you could lower your high blood sugar by just flushing it right down the toilet?
A couple of pharma companies are working on a therapy that may do just that. Their treatment, called an SGLT2 inhibitor, causes your extra blood sugar to flow harmlessly away in your urine. To understand how an SGLT2 (sodium glucose transporter 2) inhibitor works, you have to know a little about what the kidneys do.
Every time the heart beats, about 20 percent of the blood it pumps out goes to the kidneys to be cleaned. The blood ends up in a tuft of tiny blood vessels, called a glomerulus, which is surrounded by a cup-like sac, called a Bowman’s capsule. Each kidney has a million or so of these little arrangements.
High blood pressure in the glomerulus forces all the small molecules in the blood right through the blood vessel walls and into the Bowman’s capsule, where they begin their journey down a little tubule toward the bladder. This liquid filtrate contains not only waste products, which the body wants to get rid of, but also a lot of useful molecules, which the body doesn’t want to lose. One of those useful molecules is glucose.
The body has to have a way to re-absorb that glucose back into the blood, and that’s where SGLT2 comes into play. As the filtrate moves down the tubule, SGLT2 grabs almost all of the glucose going by and pulls it back into the walls of the tubule, from whence it can be moved back into the blood and used by the body.
An SGLT2 inhibitor prevents SGLT2 from doing its job. If SGLT2 can’t grab the glucose, that glucose is on its way to the sewage treatment plant. It’s a novel way to lower blood sugar in people with diabetes, and it might work well for obesity too. Studies have shown that such inhibitors may cause the excretion of up to 90 grams of glucose per day, and each gram is worth four calories.
There is no SGLT2 inhibitor on the market yet, but a company called Sirona Biochem announced recently that in a preclinical trial, its SGLT2 inhibitor reduced blood glucose levels in a dose-dependent manner by as much as 50 percent compared to untreated groups. Another SGLT2 inhibitor, called dapagliflozin, is being studied in clinical trials by Bristol-Myers Squibb and AstraZeneca as a treatment for diabetes.