Pulmonary manifestations of prolidase deficiency.

BACKGROUND: Prolidase deficiency is a rare autosomal recessive disease, in which pulmonary manifestations have been sporadically reported. AIMS: We have encountered two patients who presented with severe pulmonary cystic lesions leading to respiratory failure. This led us to retrospectively evaluate pulmonary involvement in patients with prolidase deficiency treated in our hospital. RESULTS: Of 21 patients (including the 2 mentioned above), 12 had a history of recurrent pulmonary infections and 10 were diagnosed as having chronic lung disease. Of seven chest CT scans performed, four patients had subpleural cysts, two patients had bronchiectatic changes, and one had diffused ground glass attenuation and minor linear atelectasis. Three patients died, with all deaths being attributed to respiratory insufficiency. CONCLUSIONS: Prolidase deficiency is frequently associated with various pulmonary manifestations, including extensive cystic changes that may be life endangering. The differential diagnosis of bilateral cystic changes should include prolidase deficiency, and pulmonary evaluation should be performed in patients with prolidase deficiency. Pediatr Pulmonol. 2016;51:1229-1233. © 2016 Wiley Periodicals, Inc.

Activity of prolidase isoenzymes in the rat brain: subcellular and regional distribution during development.

Prolidase deficiency is characterized by chronic ulcerative dermatitis, mental retardation, and frequent infections. In the present study we examined the characteristics of rat brain prolidase isoenzymes. Prolidase isoenzymes (PD I and PD II) were isolated from the rat brain using DEAE cellulose column chromatography. PD I showed higher activity against seryl-proline and alanyl-proline, while PD II was particularly active against methionyl-proline. Prolidase activity in the whole brain and in the different brain regions showed higher activity against methionyl-proline and seryl-proline. PD II activity was highest in the hippocampus, followed by the cerebellum, cerebral cortex, caudatum, and the midbrain. The most rapid changes in the activities of PD I and PD II occurred perinatally, with a peak at three days before birth and a nadir at two days after birth, which then gradually increased until 21 days. N-benzyloxycarbonyl-l-proline inhibited PD I activity against various substrates in a dose-dependent manner. In contrast, there was no inhibition of PD II activity against methionyl-proline at low concentrations. In summary, these data suggest that maintenance of levels of proline, other amino acids and peptides containing proline in the rat brain is regulated by prolidase isoenzymes. The age-related alterations in PD I and PD II also may help to elucidate the fundation of prolidase isoenzymes in brain nervous system.