Renal growth factors: Past, present and future

It is known that a series of mediators, so-called growth factors, are able to induce hypertrophy of the kidney in a patient after uninephrectomy. The first investigator who demonstrated this phenomenon was C. Sacerdotti, an I talian pathologist of Bizzozero's School in Turin, who published an importa nt report in 1896. He attempted to explain how compensatory renal hypertrop hy occurred and how this hypertrophy might be induced in a normal dog. Inte restingly, he demonstrated that when the kidneys of a normal dog received a blood transfusion from uni- or binephrectomized dogs several mitoses appea red in the renal epithelium. These mitoses, expression of renal hypertrophy , were more evident in dogs receiving several blood transfusions for 6-7 da ys. He concluded that hypertrophy was induced by specific substances circul ating in the blood of uni- or binephrectomized dogs. This hypothesis was in the next 100 years confirmed by the discovery of renal growth factors such as epidermal growth factor, insulin-like growth factor-1, hepatocyte growt h factor, platelet-derived growth factor and others. The pathogenic role of these mediators is evident in the recovery of tubules after acute tubular necrosis and in the remnant glomeruli after glomerular damage. Today, attem pts to use these growth factors for improving renal function in patients wi th acute tubular necrosis and to block their action in the progression of r enal damage in chronic glomerulonephritides are under investigation. Future trends in these growth factors will be set by drug companies designing spe cific therapies such as gene therapy. In conclusion, the outstanding observ ation by Sacerdotti, over a century ago, remains an important step in nephr ologic history for prognosis and therapy of renal diseases.