DJ-1 degrades transthyretin and an inactive form of DJ-1 is secreted in familial amyloidotic polyneuropathy.

DJ-1 plays roles in transcriptional regulation and anti-oxidative stress, and loss of its function is thought to result in the onset of Parkinson's disease. DJ-1 has a protease-like structure and transthyretin (TTR), a protein causing familial amyloidotic polyneuropathy (FAP), was identified as a substrate for DJ-1 protease in this study. Both TTR and DJ-1 were secreted into the culture medium under normal conditions, and secreted TTR was not aggregated. Under oxidative conditions, TTR but not DJ-1 was secreted into the culture medium, resulting in aggregation. Mirror images of both the expression patterns and solubility of DJ-1 and TTR were observed in tissues of FAP patients, and an unoxidized form of DJ-1, an inactive form, was secreted into the serum of FAP patients. These results suggest that oxidative stress to cells abrogates secretion of DJ-1 and that secreted DJ-1 degrades aggregated TTR to protect against the onset of FAP.

[Practical application of nutritional assessment protein and inflammatory marker in the nutrition support team (NST)].

Recently nutrition support team (NST) has been established for the purpose of prevention of complications which are caused by nutrition disorders and reduction of the medical expenses. Although physical examinations and blood biochemical data had been used as the indexes evaluating nutritional of patients, they were not suitable for the evaluation for the short-term in-patient. On the contrary, serum albumin (ALB) has been wildly used as a nutritional marker. However, it is impossible to evaluate nutrition state for the short-term in-patient and acute phase disease patient accurately, because the plasma half-life is 21 days and it takes long time to detect the change in nutritional state by its value. Rapid turnover proteins (RTP), whose plasma half-life is shorter, has paid attention to evaluate nutritional state for the short-term in-patients and acute phase disease patients. Although, prognostic inflammatory and nutritional index (PINI) was considered as a useful maker for evaluating inflammatory and nutritional states using the concentrations of transthyretin (TTR), a RTP, alpha1-acid glycoprotein (alpha1-AG), a chronic inflammation marker, C reactive protein (CRP), a acute inflammation marker, and ALB, However, it has several pitfalls. We newly made serum amyloid A (SAA) index using SAA instead of CRP. When we compared SAA index with PINI in many diseases, it turned out that SAA index became a more effective index which reflected the patient condition than did PINI. As for this index, it is expected to be used by NST while further alternation may be needed.

A transgenic rat with the human ATTR V30M: a novel tool for analyses of ATTR metabolisms.

Amyloidogenic transthyretin (ATTR) is the pathogenic protein of familial amyloidotic polyneuropathy (FAP). To establish a tool for analyses of ATTR metabolisms including after liver transplantations, we developed a transgenic rat model expressing human ATTR V30M and confirmed expressions of human ATTR V30M in various tissues. Mass spectrometry for purified TTR revealed that rat intrinsic TTR and human ATTR V30M formed tetramers. Congo red staining and immunohistochemistry revealed that nonfibrillar deposits of human ATTR V30M, but not amyloid deposits, were detected in the gastrointestinal tracts of the transgenic rats. At 24h after liver transplantation, serum human ATTR V30M levels in transgenic rats that received livers from normal rats became lower than detectable levels. These results thus suggest that this transgenic rat may be a useful animal model which analyzes the metabolism of human ATTR V30M including liver transplantation studies.

FK506 inhibits murine AA amyloidosis: possible involvement of T cells in amyloidogenesis.

OBJECTIVE: To determine the possibility that T cells represent a potential target for therapy in AA amyloidosis. METHODS: AA amyloidosis was induced in C3H/HeN mice by concomitant administration of AgNO3 and amyloid-enhancing factor (AEF). Mice injected with AgNO3 and AEF received intraperitoneal injections of FK506 (2-200 microg/day). The degree of splenic amyloid deposition was determined by Congo red staining. Serum amyloid A (SAA), interleukin 1beta (IL-1beta), IL-6, and tumor necrosis factor-a concentrations were measured by ELISA. AA amyloidosis was also induced in ICR mice by injection of Freund's complete adjuvant (FCA) and Mycobacterium butyricum without AEF. ICR mice injected with FCA and M. butyricum also received intraperitoneal injections of FK506 (200 microg/day) to eliminate the possibility that FK506 action might depend upon AEF activity in the amyloid formation. Amyloid deposition was also induced with and without AEF in severe combined immunodeficient (SCID) mice and nude mice to clarify the role of T cells in the mechanism of amyloid formation in AA amyloidosis. RESULTS: FK506 treatment significantly reduced the amount of amyloid deposition and incidence of amyloidosis without reducing serum SAA and proinflammatory cytokine levels in the murine AA amyloidosis models with and without AEF. SCID mice and nude mice showed resistance to development of AA amyloidosis. CONCLUSION: Our findings may provide a new therapeutic strategy for amyloidosis. The results suggested that T cells may play an important role in the mechanism of amyloid formation in AA amyloidosis.