StemCell Therapy

About the kidney

The kidneys are towards the back of the body, roughly 10 cm above the hipbones and just below the ribcage. They are the bodys filtering units, maintaining a safe balance of fluid, minerals, salts and other substances in the blood. They produce urine to remove waste and harmful substances from the body. They also produce several hormones: erythropoietin (EPO), which acts on the bone marrow to increase the production of red blood cells; calcitriol (active Vitamin D3), which promotes absorption and use of calcium and phosphate for healthy bones and teeth; and the enzyme renin, which is involved in monitoring and controlling blood pressure.

The key working component of the kidney is the nephron.

The nephron - the functional unit of the kidney: The best evidence so far for stem cells in the adult kidney suggests they might be found in the blue area, called the urinary pole. Some studies have also suggested stem cells may be found in the parts of the nephron marked in green.

The nephron is made up of:

Kidney diseases usually involve damage to the nephrons and can be acute or chronic. In acute kidney disease there is a sudden drop in kidney function. It is usually caused by loss of large amounts of blood or an accident and is often short lived, though it can occasionally lead to lasting kidney damage. Chronic kidney disease (CKD) is defined as loss of a third or more of kidney function for at least three months. In CKD kidney function worsens over a number of years and the problem often goes undetected for many years because its effects are relatively mild. Some of the symptoms associated with CKD are: headache, fatigue, high blood pressure, itching, fluid retention, shortness of breath.

However, kidney disease can lead to kidney failure (less than 10% kidney function). Once this happens, patients need dialysis or a kidney transplant to stay alive. The risk of developing CKD is increased by old age, diabetes, high blood pressure, obesity and smoking. At least 8% of the European population (40 million individuals) currently has a degree of CKD, putting them at risk of developing kidney failure. This figure is increasing every year and there are not enough organ donors to provide transplants for so many patients. This makes the development of new therapeutic options for treating CKD increasingly important.

Scientists are still debating whether kidney stem cells exist in the adult body and if so, where they are found and how they can be identified. Cells found in a number of places within the nephrons have been proposed as candidates for kidney stem cells. The most convincing evidence for the existence of such stem cells is the discovery of a group of cells at the urinary pole of the Bowmans capsule of the nephron (marked in blue in the diagram above). These cells have some of the key features of stem cells and researchers have shown them to be responsible for production of podocytes specialised cells involved in the filtration work of the nephron and that need to be replaced continuously throughout our lifetime. Studies also suggest that these same proposed stem cells might be able to generate a second type of specialised cell found in the nephron lining, called proximal tubular epithelial cells. Other suggested locations for kidney stem cells include certain places in the tubules (marked green in the diagram). As well as kidney stem cells, cells with some of the characteristics of mesenchymal stem cells have very recently been isolated from the kidney.

A number of different types of cells from the bone marrow have been tested in animals and in clinical studies for potential use in kidney disease. Amongst all the cells under investigation, mesenchymal stem cells (MSCs) have shown the most promising results to date. Studies suggest that MSCs may be able to enhance the intrinsic ability of the kidney to repair itself.

MSCs of the bone marrow can differentiate to produce specialised bone, fat and cartilage cells. Researchers investigating the therapeutic effects of these MSCs within the kidney have suggested these cells may release proteins that can help kidney cells to grow, inhibit cell death and that could encourage the kidneys own stem cells to repair kidney damage. Further research is needed to establish whether these ideas are correct and if so, how this could lead to a treatment for patients.

The rest is here:
Kidney disease: how could stem cells help? | Europe's stem ...

This entry was posted on May 19, 2015 at 6:52 pm and is filed under Stem Cell kidney Failure. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed. |