Hyperkyphosis is not dependent on bone mass and quality in the mouse model of Marfan syndrome

Extracellular matrix and vascular dynamics in the kidney of a murine model for Marfan syndrome

Fibrillin-1 is a pivotal structural component of the kidney's glomerulus and peritubular tissue. Mutations in the fibrillin-1 gene result in Marfan syndrome (MFS), an autosomal dominant disease of the connective tissue. Although the kidney is not considered a classically affected organ in MFS, several case reports describe glomerular disease in patients. Therefore, this study aimed to characterize the kidney in the mgΔlpn-mouse model of MFS. Affected animals presented a significant reduction of glomerulus, glomerulus-capillary, and urinary space, and a significant reduction of fibrillin-1 and fibronectin in the glomerulus. Transmission electron microscopy and 3D-ultrastructure analysis revealed decreased amounts of microfibrils which also appeared fragmented in the MFS mice. Increased collagen fibers types I and III, MMP-9, and α-actin were also observed in affected animals, suggesting a tissue-remodeling process in the kidney. Video microscopy analysis showed an increase of microvessel distribution coupled with reduction of blood-flow velocity, while ultrasound flow analysis revealed significantly lower blood flow in the kidney artery and vein of the MFS mice. The structural and hemodynamic changes of the kidney indicate the presence of kidney remodeling and vascular resistance in this MFS model. Both processes are associated with hypertension which is expected to worsen the cardiovascular phenotype in MFS.

"Split-Face" Evaluation of Collagen Changes Induced by Periorbital Fractional CO2 Laser Resurfacing

BACKGROUND

Periorbital fractional CO2 laser resurfacing has been employed for facial rejuvenation purposes. However, to the best of our knowledge, no study has objectively assessed periorbital neoformation and remodeling of local cutaneous collagen, in a split-face model, from skin samples obtained during upper blepharoplasty.

OBJECTIVES

The authors sought to objectively evaluate neoformation and remodeling of local cutaneous collagen after periorbital skin fractional CO2 laser resurfacing.

METHODS

Sixteen female patients presenting with dermatochalasis and periorbital rhytids were evaluated in a prospective and comparative study. All patients underwent unilateral periorbital fractional CO2 laser resurfacing 30 days before upper blepharoplasty. Quantification of types I and III collagen from laser-treated and untreated eyelid skin samples obtained during upper blepharoplasty was assessed with histochemical analysis (Picrosirius Red staining). Laser resurfacing treatment was applied to the untreated side immediately after the upper blepharoplasty. Two blinded, independent physicians evaluated clinical improvement in pretreatment and 1- and 6-month posttreatment digital images.

RESULTS

Histochemical analysis showed significantly higher intensity in collagen types I (treated: 158.7 ± 5.3, untreated: 139.2 ± 5.0; P < 0.0001) and III (treated: 105.1 ± 7.7, untreated: 104.1 ± 7.1; P < 0.0001) in the fractional CO2 laser treatment samples; a greater difference was detected in collagen type I. A significant improvement in periorbital rhytidosis was observed 1 month after laser resurfacing (23%); a greater improvement in the periorbital region was observed 6 months after laser resurfacing and upper blepharoplasty (43.67%).

CONCLUSIONS

Periorbital fractional CO2 laser resurfacing was an effective method to improve palpebral skin, with histochemical evidence of increase in collagen types I and III.

LEVEL OF EVIDENCE: 4