Ntaining membranes, suggesting that it has a function in clearance of late apoptotic cells [5?0]. Amyloidosis designates diseases involving the deposition of fibrillar proteins, mainly in extracellular spaces. Accumulation of amyloid fibrils is associated with cellular dysfunction and cell death [11,12]. At least 27 different human proteins are known to cause amyloidosis [13], the best known being the Ab peptide(which is associated with Alzheimer’s disease), prion protein, and transthyretin (TTR). TTR is found in blood plasma, the cerebrospinal fluid, and the vitreous humor of the eye. It is composed of four identical Octapressin biological activity subunits of 127 amino acids rich in b-structures [14]. Its biological role in the transport of the thyroid hormone thyroxine and of retinol (via retinol-binding protein) is well established [15,16]. TTR is deposited as amyloid fibrils in three pathological conditions. Senile systemic amyloidosis occurs mainly in males at advanced age, with predominant manifestation in the heart due to deposits of wild-type TTR [17]. Familial forms of TTRrelated amyloidosis are inherited in an autosomal dominant manner and arise from single point mutations in the coding sequence of the TTR gene. These forms of TTR-related amyloidosis are characterized by deposition in several organs including the intestine, the vitreous body of the eye, and particularly along peripheral nerves. The typical manifestation is polyneuropathy, which affects motor, sensory, and autonomous functions; this form has therefore been termed familial amyloid polyneuropathy. However, some mutations in the TTR geneSAP and Aggregation-Induced Cell Deathare associated with amyloid deposits found mainly in cardiac tissue, which lead to familial amyloid cardiomyopathy (for review, see [18]). Amyloid consists of aggregated proteins with an ordered fibril structure. In addition, all types of amyloid are decorated with a number of CAL 120 site non-fibrillar constituents, the identity of which is essentially independent of the precursor protein making up the fibrils. These universal non-fibrillar components include SAP [19] and glycosaminoglycans, especially heparan sulfate, dermatan sulfate, and chondroitin sulfate [20]. The amount of SAP in amyloid deposits might be remarkably high, as up to 20 g of SAP per kg dry weight of amyloid fibril has been reported (even though the plasma pool of SAP remained unchanged) [21]. The exact role of these molecules in 18325633 amyloidogenesis is unknown; none of the structural details of their interaction with amyloid fibrils are known either. However, their universal presence in all known deposits suggests that they have a functional role with as yet unknown clinical consequences. Reports on the role of SAP in amyloid formation are contradictory, since both inhibition [22] and promotion of aggregation [23,24] have been shown in the case of the Ab peptide of Alzheimer’s disease. Since SAP is the major acute-phase reactant in mice, lipopolysaccharide (LPS) can be used to trigger its production. However, forced expression of SAP by LPS has not been found to increase the formation of TTR amyloid in transgenic mice carrying the human TTR gene [25]. Interestingly, mice deficient in SAP develop Ab amyloid that is similar histochemically to deposits in normal mice, although amyloid formation is delayed and its quantity reduced [26]. More than 100 mutations of TTR are known to date (http://www. bumc.bu.edu/Dept/Content. aspx?DepartmentID = 354 PageID = 5530). Most of them.Ntaining membranes, suggesting that it has a function in clearance of late apoptotic cells [5?0]. Amyloidosis designates diseases involving the deposition of fibrillar proteins, mainly in extracellular spaces. Accumulation of amyloid fibrils is associated with cellular dysfunction and cell death [11,12]. At least 27 different human proteins are known to cause amyloidosis [13], the best known being the Ab peptide(which is associated with Alzheimer’s disease), prion protein, and transthyretin (TTR). TTR is found in blood plasma, the cerebrospinal fluid, and the vitreous humor of the eye. It is composed of four identical subunits of 127 amino acids rich in b-structures [14]. Its biological role in the transport of the thyroid hormone thyroxine and of retinol (via retinol-binding protein) is well established [15,16]. TTR is deposited as amyloid fibrils in three pathological conditions. Senile systemic amyloidosis occurs mainly in males at advanced age, with predominant manifestation in the heart due to deposits of wild-type TTR [17]. Familial forms of TTRrelated amyloidosis are inherited in an autosomal dominant manner and arise from single point mutations in the coding sequence of the TTR gene. These forms of TTR-related amyloidosis are characterized by deposition in several organs including the intestine, the vitreous body of the eye, and particularly along peripheral nerves. The typical manifestation is polyneuropathy, which affects motor, sensory, and autonomous functions; this form has therefore been termed familial amyloid polyneuropathy. However, some mutations in the TTR geneSAP and Aggregation-Induced Cell Deathare associated with amyloid deposits found mainly in cardiac tissue, which lead to familial amyloid cardiomyopathy (for review, see [18]). Amyloid consists of aggregated proteins with an ordered fibril structure. In addition, all types of amyloid are decorated with a number of non-fibrillar constituents, the identity of which is essentially independent of the precursor protein making up the fibrils. These universal non-fibrillar components include SAP [19] and glycosaminoglycans, especially heparan sulfate, dermatan sulfate, and chondroitin sulfate [20]. The amount of SAP in amyloid deposits might be remarkably high, as up to 20 g of SAP per kg dry weight of amyloid fibril has been reported (even though the plasma pool of SAP remained unchanged) [21]. The exact role of these molecules in 18325633 amyloidogenesis is unknown; none of the structural details of their interaction with amyloid fibrils are known either. However, their universal presence in all known deposits suggests that they have a functional role with as yet unknown clinical consequences. Reports on the role of SAP in amyloid formation are contradictory, since both inhibition [22] and promotion of aggregation [23,24] have been shown in the case of the Ab peptide of Alzheimer’s disease. Since SAP is the major acute-phase reactant in mice, lipopolysaccharide (LPS) can be used to trigger its production. However, forced expression of SAP by LPS has not been found to increase the formation of TTR amyloid in transgenic mice carrying the human TTR gene [25]. Interestingly, mice deficient in SAP develop Ab amyloid that is similar histochemically to deposits in normal mice, although amyloid formation is delayed and its quantity reduced [26]. More than 100 mutations of TTR are known to date (http://www. bumc.bu.edu/Dept/Content. aspx?DepartmentID = 354 PageID = 5530). Most of them.
