Studies On Resembling The Cutis Laxa Syndrome In Sika Deer

Cutis laxa is a heterogeneous group of rare inherited and acquired connective tissue disorders,whose common feature is occurrence of loose and redundant skin with decreased elasticity. Thetypical clinical feature of CL patient is that the skin can be easily pulled away from the underlyingtissue, but it can’t return to its original position after the release in a short time. The incidence rateof the rare hereditary disease was1-2:400000, and acquired CL have a lower incidence. We firstobserved obvious sagging skin disease in the neck of three adult male deer. To confirm thediagnosis, the skin histology was studied by light and electron microscopy, the molecular biologywas examined by sequencing the ELN and Fibulin-5gene mutation, immunohistochemistry andReal-time fluorescent quantitative PCR was used to study the ELN and Fibulin-5gene expression.The results were as follows:1Histologic examination of skin sections showed destruction morphology of elastin fbersand collagen fibers, the elastic fibers appeared severe hypoplasia with isolated, disorganized, smallfragmented and clumped appearance in the reticular dermis of cutis laxa deer. The collagen fibersshowed severe sparse.2In the reticular dermis of cutis laxa deer, many elastin fibres were seen to be highlyabnormal in both shape and electron density. Some fibres showed a loosely organized, missing ordamaged appearance. Situated within a loose matrix of widely dispersed collagen bundles, theyshowed many amorphous component in the regions of the elastic material and the separate elasticglobules. There are many branches and debris in amorphous component of elastic fibers.3Three synonymous mutation, which was not present in healthy control sika deer, c.601C>G,c.1030C>T and c.1081C>T were identified in No.0of Fibulin-5gene. Also, there was asynonymous mutation occurring at c.601C> G in No.33cutis laxa deer.4The ELN, Fibulin-5and LOX1gene in the neck skin of sika deer were expressed in theextracellular matrix. ELN was strongly expressed in the control group and weakly expressed incutis laxa sika deer; The intensity of Fibulin-5expression was significantly lower than the control group; LOX1was distributed densely with positive expression in the control group compared tocutis laxa deer, which expressed sparse and low.5The ELN mRNA expression level of cutis laxa sika deer was significantly higher than thatof control group. The Fibulin-5expression levels of cutis laxa sika deer was increased overall,however, the expression levels of No.33and control group was similar, No.0deer increased moresignificantly. LOX1expressed stably in cutis laxa sika deer, and showed almost the sameexpression with the control group.