Liver growth factor (LGF) is a liver mitogen with regenerating and anti-fibrotic activity even at extrahepatic sites. We used LGF in a lung fibrosis model induced by cadmium chloride (CdCl2), to study its antifibrotic capacity.
Forty-two male Wistar rats were administered a single dose of 0.5 ml/rat of CdCl2 0.025 % (n=21) or the same volume of saline (control group, n=21). After 35 days, once a lesion was established, we started a 3 week treatment with LGF, after which we determined lung function ¡ªinspiratory capacity (IC), lung compliance (LC), forced vital capacity (FVC) and expiratory flow at 75 % (FEF75 % )? lung morphometry ¡ªalveolar internal area (AIA), mean linear intersection (LM)? and collagen (both by Sirius red and hydroxyproline residues) and elastin contents.
Pulmonary fibrosis in CdCl2 rats was characterized by a marked decrease in pulmonary function with respect to healthy controls ¡ªreductions of 28 % in IC, 38 % in CL, 31 % in FVC, and 54 % in FEF75 % ?which was partially recovered after LGF injection ?8 % IC, 27 % CL, 19 % FVC and 35 % FEF75 % ? increase in collagen and elastin contents ?65 % and 76 % , respectively, in CdCl2 rats, versus 110 % and 34 % after LGF injection? and increases in AIA and LM, partially reverted by LGF. Conclusions: Together, these data seem to demonstrate that LGF is able to improve lung function and partially reverts the increase in lung matrix proteins produced by CdCl2 instillation.