Expression of apoptosis regulatory proteins p53 and Bcl-2 in skin of patients with chronic renal failure on maintenance haemodialysis.
BACKGROUND
Chronic renal failure results in multi-organ system derangement including cardiovascular, gastrointestinal, neurological, endocrinal, blood and dermatological abnormalities. Maintenance of skin homeostasis requires a delicate balance between proliferation, differentiation and apoptosis. p53 and Bcl-2 proteins play a central role in the regulation of apoptosis.


OBJECTIVE
Evaluation of the expression of apoptosis regulatory proteins p53 and Bcl-2 in apparently normal skin of patients, with chronic renal failure on maintenance haemodialysis, with respect to their role in the apoptotic process.


METHODS
Biopsy specimens were obtained from 10 patients with chronic renal failure on maintenance haemodialysis, as well as seven age-matched control subjects. Computer-assisted image analysis was employed to measure epidermal thickness in H&E-stained sections. Immunoperoxidase technique was also used to demonstrate p53 and Bcl-2 proteins and the TUNEL technique for detection of apoptotic cells in these specimens.


RESULTS
The mean epidermal thickness was significantly higher (P < 0.0001) in patients than controls. Meanwhile, no apoptotic cells were detected in the epidermis of patients. On the other hand, a statistically significant difference was observed in both p53 (P = 0.0001) and Bcl-2 expression (P = 0.0003) when comparing patients and controls. Expression of p53 (2.74 +/- 0.84) and Bcl-2 (3.45 +/- 1.35) proteins was higher in skin samples obtained from patients with chronic renal failure and on maintenance haemodialysis than those from control cases (0.5 +/- 0.96 and 0.8 +/- 0.6, respectively). Moreover, Bcl-2 expression in patients was observed in basal as well as squamous cell layers of skin, whereas in control subjects it was confined to the basal cell layer only.


CONCLUSIONS
These findings suggest that an alteration in the proliferation/apoptosis balance may be present in the skin of such patients.
El-Domyati
M M
MM
Department of Dermatology, Faculty of Medicine, Al-Minya University, Al-Minya, Egypt. m_domyati@hotmail.com
Ahmad
H M
HM
Nagy
I
I
Zahran
A
A
D000328:Adult; D051017:Apoptosis Regulatory Proteins / Q000378:metabolism*; D001706:Biopsy; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D020287:In Situ Nick-End Labeling; D007676:Kidney Failure, Chronic / Q000628:therapy*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D006435:Renal Dialysis; D012867:Skin / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*
D051017:Apoptosis Regulatory Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D016159:Tumor Suppressor Protein p53