Structural changes in dermal collagen and oxidative stress levels in the skin of Japanese overweight males.

OBJECTIVE: It has been reported that obese people have poorly organized dermal collagen structure because of the degradation of collagen fibers, which is caused by an increase in oxidative stress levels associated with the hypertrophy of subcutaneous adipose cells. However, it is unclear whether an increase in oxidative stress levels caused by the accumulation of subcutaneous adipose tissue and a change in the dermal structure also occur in overweight and obese Japanese people. The objectives of this study are to identify structural changes that occur in the dermis and to measure the levels of oxidative stress in Japanese overweight males. METHODS: The overweight group included 43 Japanese male volunteers aged between 25 and 64 years and with a body mass index (BMI) of ≥25 and <30. The control group included 47 male volunteers aged between 22 and 64 years and with BMI of <25. The 20-MHz Dermascan C® ultrasound scanner with software for image analyses was used. Echogenicity of the upper and lower dermis was measured. The mRNA expression level of heme oxygenase-1 (HMOX1) in hair follicles was quantitatively analyzed by real-time reverse transcription polymerase chain reaction (RT-PCR) and was used as a marker of oxidative stress. Ultrasonographic imaging and collection of hair follicles were performed at the same site on the thigh, abdomen, and upper arm. RESULTS: The HMOX1 mRNA expression level in the abdomen and thigh was significantly lower in the overweight group than in the control group. Moreover, the echogenicity of the upper dermis of the abdomen and the lower dermis of the abdomen and thigh was significantly lower in the overweight group than in the control group. CONCLUSION: We detected an increase in oxidative stress levels and a decrease in the density of dermal collagen at the same site on the thigh, abdomen, and upper arm of Japanese overweight males. These findings suggest the fragility of the dermis of Japanese overweight males, which might have been caused by the accumulation of subcutaneous adipose tissue.

Antigenic differentiation of turkey rhinotracheitis virus strains using monoclonal antibodies and polyclonal antisera.

Monoclonal antibodies (mAbs) were prepared against the 8597/CV94 strain of turkey rhinotracheitis virus (TRTV). These mAbs were used to investigate antigenic relationships among three strains (8597/CV94, 1162/92 and CVL14/1 strain) of TRTV, together with polyclonal chicken and rabbit antisera to 8597/CV94 strain, and guinea pig antisera to each of the three strains. Thirty mAbs to the glycoprotein (G:3 clones), fusion (F1:6 clones), phosphorylated (P:6 clones), nucleocapsid (N:12 clones), and matrix (M:3 clones) proteins of viral antigen were obtained by cell fusion. Among these, two mAbs to F1 protein showed virus neutralizing activity. The results of ELISA test indicated that some mAbs only reacted to the 8597/CV94 strain, some reacted to 8597/CV94 and 1162/92 strains, and others reacted to all three viral strains. In neutralization tests with the three virus strains, polyclonal chicken and rabbit antisera against the 8597/ CV94 strain showed the same antibody titers. Results with four neutralizing mAbs including two previously reported mAbs [Ref. 21] indicated the titers of two mAbs (Pn2-2E and Pn3-2F) to 8597/CV94 were much higher than those to the other two viral strains. No differences were observed in the titers of the other two mAbs (Pn01-8E and Pn06-4D) against any viral strains. In cross-neutralization tests with polyclonal guinea pig antisera, there was some variations among viral strains. This work demonstrated that the Japanese isolate 8597/CV94 of TRTV is somewhat different in antigenicity from two British isolates from chickens and turkeys.