Role of Serum Amyloid A Protein in the Early Detection of Late Onset Sepsis in Neonate

Serum Amyloid A (SAA) is an Acute-Phase Protein (APP) produced as an innate nonspecific response to any tissue damage. Hence, it plays a significant role in chronic inflammatory diseases. In particular, SAA levels increase dramatically in chronic periodontitis and chronic apical periodontitis. Recent studies suggest this role of SAA in the pathogenesis of various diseases, including chronic periodontitis and chronic apical periodontitis. Thus, the focus of this review is to sum up the current understanding of the role of SAA in health and disease and to elaborate on possible mechanisms by which SAA could play a role in the pathogenesis of chronic periodontitis and chronic apical periodontitis.

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Serum Amyloid A, Procalcitonin, Tumor Necrosis Factor-α, and Interleukin-1βLevels in Neonatal Late-Onset Sepsis

Mediators of Inflammation ◽

10.1155/2008/737141 ◽

2008 ◽

Vol 2008 ◽

pp. 1-7 ◽

Cited By ~ 22

Author(s):

Birsen Ucar ◽

Bilal Yildiz ◽

M. Arif Aksit ◽

Coskun Yarar ◽

Omer Colak ◽

...

Keyword(s):

Serum Amyloid A ◽

Late Onset ◽

Serum Amyloid ◽

Amyloid A ◽

Late Onset Sepsis ◽

Sepsis Score ◽

Reliable Marker ◽

Factor Α ◽

Necrosis Factor

Background. Sepsis is an important cause of mortality in newborns. However, a single reliable marker is not available for the diagnosis of neonatal late-onset sepsis (NLS). The aim of this study is to evaluate the value of serum amyloid A (SAA) and procalcitonin (PCT) in the diagnosis and follow-up of NLS.Methods. 36 septic and healthy newborns were included in the study. However, SAA, PCT, TNF-α, IL-1β, and CRP were serially measured on days 0, 4, and 8 in the patients and once in the controls. Töllner's sepsis score (TSS) was calculated for each patient.Results. CRP, PCT, and TNF-αlevels in septic neonates at each study day were significantly higher than in the controls (P=.001). SAA and IL-1βlevels did not differ from healthy neonates. The sensitivity and specificity were 86.8% and 97.2% for PCT, 83.3% and 80.6% for TNF-α, 75% and 44.4% for SAA on day 0.Conclusion. Present study suggests that CRP seems to be the most helpful indicator and PCT and TNF-αmay be useful markers for the early diagnosis of NLS. However, SAA, IL-1β, and TSS are not reliable markers for the diagnosis and follow-up of NLS.

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SAT0105 Inflammatory Markers in Rheumatoid Arthritis – What Is The Role of Serum Amyloid A Protein?

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2016-eular.4791 ◽

2016 ◽

Vol 75 (Suppl 2) ◽

pp. 703.2-703

Author(s):

D.R. Gonçalves ◽

R. Fonseca ◽

F. Aguiar ◽

T. Martins-Rocha ◽

M. Bernardes ◽

...

Keyword(s):

Rheumatoid Arthritis ◽

Inflammatory Markers ◽

Serum Amyloid A ◽

Serum Amyloid ◽

Amyloid A ◽

Serum Amyloid A Protein

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Cleavage, down-regulation and aggregation of serum amyloid A

10.1101/811398 ◽

2019 ◽

Author(s):

Wenhua Wang ◽

Prabir Khatua ◽

Ulrich H.E. Hansmann

Keyword(s):

Serum Amyloid A ◽

Serum Amyloid ◽

Amyloid Formation ◽

Dynamic Simulations ◽

Over Expression ◽

Amyloid A ◽

Serum Amyloid A Protein ◽

Ph Increase ◽

The One

AbstractVarious diseases cause over-expression of the serum amyloid A protein (SAA), which leads in some, but not all, cases to amyloidosis as a secondary disease. The response to the over-expression involves dissociation of SAA hexamer and subsequent cleavage of the released monomers, most commonly yielding fragments SAA1−76 of the full-sized SAA1−104. We report results from molecular dynamic simulations that probe the role of this cleavage for down-regulating activity and the concentration of SAA. We propose a mechanism that relies on two elements. First, the probability to assemble into hexamers is lower for the fragments than it is for the full-sized protein. Second, unlike other fragments SAA1−76 can switch between two distinct configurations. The first kind is easy to proteolyze (allowing a fast reduction of SAA concentration) but prone to aggregation, while the situation is opposite for the second kind. If the time scale for amyloid formation is longer than the one for proteolysis, the aggregation-prone species dominates. However, if environmental conditions such as low pH increase the risk of amyloid formation, the ensemble shifts toward the more protected form. We speculate that SAA amyloidosis is a failure of the switching mechanism leading to accumulation of the aggregation-prone species and subsequent amyloid formation.

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Expression of serum amyloid A protein in the absence of the acute phase response does not reduce HDL cholesterol or apoA-I levels in human apoA-I transgenic mice

The Journal of Lipid Research ◽

10.1016/s0022-2275(20)32143-x ◽

1999 ◽

Vol 40 (4) ◽

pp. 648-653 ◽

Cited By ~ 7

Author(s):

Hiroshi Hosoai ◽

Nancy R. Webb ◽

Jane M. Glick ◽

Uwe J.F. Tietge ◽

Matthew S. Purdom ◽

...

Keyword(s):

Transgenic Mice ◽

Acute Phase ◽

Acute Phase Response ◽

Serum Amyloid A ◽

Hdl Cholesterol ◽

Phase Response ◽

Serum Amyloid ◽

Amyloid A ◽

Serum Amyloid A Protein

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The potential role of glycosaminoglycans in serum amyloid A fibril formation by in silico approaches

Matrix Biology Plus ◽

10.1016/j.mbplus.2021.100080 ◽

2021 ◽

pp. 100080

Author(s):

Martyna Maszota-Zieleniak ◽

Annemarie Danielsson ◽

Sergey A. Samsonov

Keyword(s):

In Silico ◽

Serum Amyloid A ◽

Potential Role ◽

Fibril Formation ◽

Serum Amyloid ◽

Amyloid A

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Aggregation of Mouse Serum Amyloid A Protein Was Promoted by Amyloid-Enhancing Factors with the More Genetically Homologous Serum Amyloid A

International Journal of Molecular Sciences ◽

10.3390/ijms22031036 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1036

Author(s):

Xuguang Lin ◽

Kenichi Watanabe ◽

Masahiro Kuragano ◽

Kiyotaka Tokuraku

Keyword(s):

Amino Acid ◽

Serum Amyloid A ◽

Animal Species ◽

Amino Acid Sequences ◽

Serum Amyloid ◽

Mouse Serum ◽

Aa Amyloidosis ◽

Basic Residue ◽

Amyloid A ◽

Serum Amyloid A Protein

Amyloid A (AA) amyloidosis is a condition in which amyloid fibrils characterized by a linear morphology and a cross-β structure accumulate and are deposited extracellularly in organs, resulting in chronic inflammatory diseases and infections. The incidence of AA amyloidosis is high in humans and several animal species. Serum amyloid A (SAA) is one of the most important precursor amyloid proteins and plays a vital step in AA amyloidosis. Amyloid enhancing factor (AEF) serves as a seed for fibril formation and shortens the onset of AA amyloidosis sharply. In this study, we examined whether AEFs extracted and purified from five animal species (camel, cat, cattle, goat, and mouse) could promote mouse SAA (mSAA) protein aggregation in vitro using quantum-dot (QD) nanoprobes to visualize the aggregation. The results showed that AEFs shortened and promoted mSAA aggregation. In addition, mouse and cat AEFs showed higher mSAA aggregation-promoting activity than the camel, cattle, and goat AEFs. Interestingly, homology analysis of SAA in these five animal species revealed a more similar amino acid sequence homology between mouse and cat than between other animal species. Furthermore, a detailed comparison of amino acid sequences suggested that it was important to mSAA aggregation-promoting activity that the 48th amino acid was a basic residue (Lys) and the 125th amino acid was an acidic residue (Asp or Glu). These data imply that AA amyloidosis exhibits higher transmission activity among animals carrying genetically homologous SAA gene, and may provide a new understanding of the pathogenesis of amyloidosis.

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