The lipid storage diseases: new concepts and control

Curious Cases of the Enzymes

Life as we know it heavily relies on biological catalysis, in fact, in a very nonromantic version of it, life could be considered as a series of chemical reactions, regulated by the guarding principles of thermodynamics. In ancient times, a beating heart was a good sign of vitality, however, to me, it is actually the presence of active enzymes that counts… Though we do not usually pay attention, the history of enzymology is as old as humanity itself, and dates back to the ancient times. This paper is dedicated to these early moments of this remarkable science that touched our lives in the past and will make life a lot more efficient for humanity in the future. There was almost always a delicate, fundamentally essential relationship between mankind and the enzymes. Challenged by a very alien and hostile Nature full of predators, prehistoric men soon discovered the medicinal properties of the plants, through trial and error. In fact, they accidently discovered the enzyme inhibitors and thus, in crude terms, kindled a sparkling area of research. These plant-derivatives that acted as enzyme inhibitors helped prehistoric men in their pursuit of survival and protection from predators; in hunting and fishing… Later in history, while the underlying purposes of survival and increasing the quality of life stayed intact, the ways and means of enzymology experienced a massive transformation, as the 'trial and error' methodology of the ancients is now replaced with rational scientific theories.

Novel therapeutic targets for the treatment of Fabry disease

Fabry disease is an X-linked lysosomal storage disorder resulting from deficient activity of alpha-galactosidase A. The traditional concept that is used to explain the complications of the disease involves progressive accumulation of globotriaosylceramide in endothelial and smooth muscle cells, resulting in vascular damage. Clinically, progressive renal insufficiency, cardiac involvement and brain pathology evolves. Two pharmaceutical companies have developed enzyme replacement therapy in Fabry disease. Although the first clinical trials showed great promise, it is clear that long-term effects are not as robust as was anticipated. Stabilisation of renal function and decreases in cardiac hypertrophy has been observed, but some patients may experience progressive complications. As there are recent indications that serum components contribute to the pathophysiology of Fabry disease, fundamental studies are needed to unravel the precise role and identity of these factors. Combination of these basic studies with clinical follow up may ultimately reveal when the 'point of no return' is reached. Advanced renal insufficiency seems to be a clinical indicator of lack of response, but other signs and symptoms are probably related to adverse outcome. It is anticipated that in the future controlled studies in early symptomatic or presymptomatic patients will be required. In addition, alternative strategies such as substrate reduction or chaperone therapy, either alone or in combination with enzyme replacement therapy, should be explored. Because Fabry disease is rare, collaborative efforts should be undertaken and openness of data should be strived for.

A new class of antivirals: antisense oligonucleotides combined with a hydrophobic substituent effectively inhibit influenza virus reproduction and synthesis of virus-specific proteins in MDCK cells

To enhance the penetration of oligonucleotide ('oligo') into cells, the oligo was combined with the hydrophobic undecyl residue. Using the 'DNA-synthesator', we synthesized oligo, complementary to the loop-forming site of the RNA, encoding polymerase 3 of the influenza virus (type A), and combined it with the undecyl residue added to the 5' terminal phosphate group. It was found that the modified oligo effectively suppresses the influenza A/PR8/34 (H1N1) virus reproduction and inhibits the synthesis of virus-specific proteins in MDCK cells. Under the same conditions, the non-modified antisense oligo and modified nonsense oligo did not affect the virus development.

The xanthogranulomatous process. Xanthogranulomatous inflammation

The precise histopathological features of the xanthogranulomatous process (XP) have been defined in an extensive review of all cases from various organs available in our files. The result was that the XP has the following aspecific but characteristic findings: the presence of granular, eosinophilic, PAS positive histiocytes in the initial stages; the mixture of foamy macrophages and activated plasma cells; the presence of suppurative foci and hemorrhages. Abscess, necrosis and most of all hemorrhages play a a role in eliciting this inflammatory response. This is in accordance with the observations so far reported in the literature. A very interesting result of our study is that some unquestionable cases of XP in cutaneous soft tissue had a histopathological picture indistinguishable from xanthoma. Basing on our experience and on an extensive study of the literature we suggest that the XP mechanism may in some way play a role in several diseases where the inflammatory or reactive nature is more or less ascertained or suspected and the secondary significance of foam cell production is overtly manifest.

Replacement therapy for inherited enzyme deficiency: liver orthotopic transplantation in Niemann-Pick disease type A

Liver homotransplantation was attempted as replacement therapy in a 2-year-old patient with near total absence of sphingomyelinase activity of Niemann-Pick disease type A. Satisfactory function of the graft was observed until the death of the recipient from respiratory complication 2 years after transplantation. The clinical stigmata of the disease became less severe during the first 6 months after transplantation, with no further improvement thereafter. Sphingomyelinase activity was restored to near normal levels in serum, was present in cerebrospinal fluid and was maintained in the graft at normal or supranormal levels. No accumulation of sphingomyelin was observed in the transplanted organ as evaluated by histopathological and chromatographic studies. These findings support the interest of organ transplantation for long-term enzyme replacement in Niemann-Pick disease type A and similar lysosomal deficiencies.