Role of the kidney in the expression of low molecular weight factors with growth factor activity.
Small molecules of peptidic nature, called low molecular weight growth factors (LMW-GF < 1000 Da) are present in normal human serum ultrafiltrate. They enhance the somatomedin activity as measured by the incorporation of 35SO4 into chick embryo cartilages. On the basis of this in vitro test, LMW-GF activities were measured in serum ultrafiltrates of hemodialyzed patients and renal transplant recipients during the post-transplantation follow-up. LMW-GF activity was always zero in patients with chronic renal failure. It was checked that these results were not due to the presence of low molecular weight somatomedin inhibitors or to the increased sulfate concentration. After successful renal transplantation, the LMW-GF activity of patients ultrafiltrates returned to normal at the same time or before the improvement of renal function. In case of post-transplant complications, a decrease in LMW-GF activity accompanied or even occurred prior to impairment of renal function. In functioning graft, LMW-GF activity reappears rapidly, whereas its normalization is delayed in case of tubular nephropathy or episode of acute rejection. It was suggested that the kidney is involved in LMW-GF molecules production or processing. It could be speculated that LMW-GF activity might be a prognostic factor in renal transplantation.
Jacob
C
C
Medical Biochemistry Laboratory, Biotechnology Institute of Nancy, Medical School, Vandoeuvre, France.
Maachi
F
F
el Farricha
O
O
Dousset
B
B
Kessler
M
M
Belleville
F
F
Nabet
P
P
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D007335:Insulin-Like Growth Factor II / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism*; D007676:Kidney Failure, Chronic / Q000097:blood*; D016030:Kidney Transplantation / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis; D013002:Somatomedins / Q000378:metabolism*
D013002:Somatomedins; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II