Ultrastructural lipid and glycoconjugate cytochemistry of membranous lipodystrophy (Nasu-Hakola disease).

In order to assess the lipid and glycoconjugate characteristics of membranous lipodystrophy, a 29-year-old male with this disease was studied using an ultrastructural cytochemical approach. The specific membranocystic lesions of the disease are composed of cystic spaces and the lining membranes. The membranes were observed to have a two-layered character: microtubular structures in the layer adjacent to the spaces and a central amorphous zone. Lipid staining and the lipase digestion test revealed triglycerides localized not only in the cystic spaces but also in the microtubular structures. Lectin histochemical examination of carbohydrate components demonstrated that Maclura pomifera agglutinin bound strongly to the membranes, while Griffonia simplicifolia I, G. simplicifolia II, Concanavalia ensiformis and Triticum vulgaris agglutinin reacted weakly. Our results indicate the presence of triglycerides and carbohydrates with mainly alpha-D-galactose residues in the distinctive membranocystic lesions, in particular in the microtubular structures.