Tumor necrosis factor-α gene promoter -308 and -238 polymorphisms and its serum level in psoriasis

BACKGROUND

Psoriasis is a chronic, immune-mediated, inflammatory skin disease affecting genetically predisposed individuals and requiring long-term treatment. The etiology of psoriasis is not fully understood. This article aimed to determine association between genetic polymorphisms in tumor necrosis factor-α (TNF -α) promoter -308 (rs1800629) and -238 (rs 361,525) and its serum level in psoriasis patients.

METHODS

The study was conducted on 70 patients with psoriasis and 70 age and sex-matched, healthy individuals. All patients were subjected to history taking and complete medical examination. The polymorphisms of TNF -α promoter gene -308 (rs1800629) and -238 (rs 361,525) were detected by real time PCR and Serum levels of TNF -α were measured by ELISA technique.

RESULTS

AG polymorphism and A allele of TNF-α -238 G/A (rs 361,525) were significantly more in patients than controls, whereas AG polymorphism and A allele of TNF-α -308 G/A (rs1800629) were significantly more in controls than patients. There were significant high levels of TNF-α in serum of patients in comparison to controls.

CONCLUSIONS

The AG polymorphism and A allele of TNF-α -238G/A (rs 361,525) may act as a risk factor for occurrence of psoriasis, whereas AG polymorphism and A allele of TNF-α -308G/A (rs1800629) may have protective role. There is pivotal role of TNF-α as a pro-inflammatory mediator in pathogenesis of psoriasis.

Valosin-containing Protein in Psoriasis: A Clinical and Immunohistochemical Study

Psoriasis is a chronic immune-mediated inflammatory skin disease, affects about 2% to 3% of the world population. Valosin-containing protein (VCP) is one of the newly discovered markers that is highly expressed in neoplasms and hyperproliferative lesions. This work aimed to study the role of VCP in psoriasis vulgaris by immunohistochemical study and correlate its expression with the available clinicopathologic data. This prospective case-control study was conducted on 25 patients with psoriasis vulgaris and 25 age-matched and sex-matched healthy individuals as a control group. Skin biopsies were taken under local anesthesia from cases and controls. VCP immunoreactivity showed that epidermal VCP expression had a significant stepwise increase (P=0.002) from control to lesional psoriatic sections. Epidermal VCP H-score was significantly associated with the progressive course (P=0.037). Similarly, VCP in the dermis showed a significant expression in lesional psoriatic skin (P≤0.001). Higher VCP in the dermis in cases with a history of joint affection (P<0.05) was detected. We concluded that VCP is a promising marker for follow-up and monitoring of psoriatic patients and may play a role as a therapeutic target.

Purification and characterization of phosphodiesterase (exonuclease) from Cerastes cerastes (Egyptian sand viper) venom

A venom exonuclease 'phosphodiesterase' (E.C. 3.1.4.1) has been purified from Cerastes cerastes venom by a combination of gel filtration on Sephadex G-100 superfine and ion exchange chromatography on DEAE-Sepharose. The enzyme showed a single band on PAGE and SDS-PAGE and had a molecular weight of 110,000. The final preparation was purified 28 fold. It had no carbohydrate and it did not have protease or 5'-nucleotidase activities. Optimum temperature for enzyme activity was 56 degrees C. The enzyme was rapidly inactivated when pre-incubated above 40 degrees C. Energy of activation (Ea) was calculated to be 0.913. The optimum pH was 9.0. Cysteine, glutathione, dithiothreitol, 2-mercaptoethanol, ADP and AMP inhibited the enzyme. Cysteine caused a non-competitive inhibition, while ADP showed a competitive inhibition. EDTA at a concentration of 0.5 mM caused complete inhibition of the enzyme, which could be reversed by the addition of Ca2+ or Mn2+.