SGLTFamilie

SGLTFamilie, often referred to as the SGLT family, comprises sodium-glucose co-transporters that mediate the active uptake of glucose and related sugars across cellular membranes. They belong to the solute carrier family SLC5 and are found in a variety of tissues, reflecting diverse physiological roles in glucose handling.

In humans, the best characterized members are SGLT1 and SGLT2. SGLT1 is highly expressed in the small intestine and also present in the kidney, where it contributes to dietary glucose absorption. SGLT2 is concentrated in the proximal tubule of the kidney and is responsible for most glucose reabsorption from the filtrate. Other members, such as SGLT3, are mainly glucose sensors rather than transporters, and additional paralogs exist with more limited tissue distribution.

Mechanism and function: SGLTs drive glucose uptake against its concentration gradient by coupling transport to the inward sodium gradient, powered by the Na+/K+ ATPase. This secondary active transport enables efficient glucose absorption and reabsorption in tissues where they are expressed. Clinically, inhibitors of SGLT2 (gliflozins) are used to treat type 2 diabetes by reducing renal glucose reabsorption and increasing urinary glucose excretion; these drugs also show cardiovascular and renal protective effects.

Evolution and structure: The SGLT family is evolutionarily conserved across vertebrates and, in some cases, other lineages. Proteins typically possess multiple transmembrane segments and are subject to regulatory mechanisms that modulate activity in response to metabolic state. The SGLT family is related to other glucose transport systems in humans, including the facilitative GLUT family.