• BMB Reports
• /
• 제40권5호
• /
• pp.662-669
• /
• 2007

Although the function of cellular prion protein (PrP$^C$) and the pathogenesis of prion diseases have been widely described, the mechanisms are not fully clarified. In this study, increases of the portion of non-glycosylated prion protein deposited in the hamster brains infected with scrapie strain 263K were described. To elucidate the pathological role of glycosylation profile of PrP, wild type human PrP (HuPrP) and two genetic engineering generated non-glycosylated PrP mutants (N181Q/N197Q and T183A/T199A) were transiently expressed in human astrocytoma cell line SF126. The results revealed that expressions of non-glycosylated PrP induced significantly more apoptosis cells than that of wild type PrP. It illustrated that Bcl-2 proteins might be involved in the apoptosis pathway of non-glycosylated PrPs. Our data highlights that removal of glycosylation of prion protein provokes cells apoptosis.

• Journal of Microbiology and Biotechnology
• /
• 제17권7호
• /
• pp.1059-1070
• /
• 2007

Prion diseases, often called transmissible spongiform encephalopathies (TSEs), are infectious diseases that accompany neurological dysfunctions in many mammalian hosts. Prion diseases include Creutzfeldt-Jakob disease (CJD) in humans, bovine spongiform encephalopathy (BSE, "mad cow disease") in cattle, scrapie in sheep, and chronic wasting disease (CWD) in deer and elks. The cause of these fatal diseases is a proteinaceous pathogen termed prion that lacks functional nucleic acids. As demonstrated in the BSE outbreak and its transmission to humans, the onset of disease is not limited to a certain species but can be transmissible from one host species to another. Such a striking nature of prions has generated huge concerns in public health and attracted serious attention in the scientific communities. To date, the potential transmission of prions to humans via foodborne infection and iatrogenic routes has not been alleviated. Rather, the possible transmission of human to human or cervids to human aggravates the terrifying situation across the globe. In this review, basic features about prion diseases including clinical and pathological characteristics, etiology, and transmission of diseases are described. Based on recently accumulated evidences, the molecular and biochemical aspects of prions, with an emphasis on the molecular interactions involved in prion conversion that is critical during prion replication and pathogenesis, are also addressed.

• 한국동물위생학회지
• /
• 제32권4호
• /
• pp.307-314
• /
• 2009

The aim of the present study was to investigate whether Bovine Spongiform Encephalopathy (BSE) is present in this country and to analyze the Global BSE Risk (GBR) status in Bangladesh. A total of 2,000 brain samples were collected from cattle older than 30 months of age, slaughtered for human consumption in the district slaughter houses from 2005 to 2006. The brainstem (obex), Pyriform lobe, cerebrum and cerebellum were subjected to histopathological study. Samples that showed some nonspecific lesions were subjected to immunohistochemistry and only brain stem to ELISA for the detection of abnormal prion protein $PrP^{sc}$. In passive surveillance, annual overall diseases of cattle, buffalo, sheep and goats in Bangladesh were collected from Department of Livestock Services (DLS), Dhaka to investigate the occurrences of neurological diseases. Import related data were collected from "National Export Promotion Bureau" Kawran Bazar, Bangladesh Bank and DLS to analyze the importing products of animal origin (cattle, buffalo, sheep and goats) from different countries to find whether or not the imported products posed any risk for the BSE. In an actire surveillance conducted in slaughter house, histopathologically BSE specific lesions were not detected in any of the brain samples, but other nonspecific lesions were observed. No $PrP^{sc}$ was detected from the samples by immunohistochemistry and ELISA. DLS report also supported the absence of BSE in cattle and buffalo and scrapie in sheep and goats in Bangladesh. It was also clearly recorded that Bangladesh imported livestock products from countries in GBR level I and II but not from countries in GBR level III and IV. From this study it apparently seems that BSE is not currently present in the indigenous animals in Bangladesh and poses no or negligible risk to human and animal health.