scholarly journals Aggregatibacter actinomycetemcomitans as the Aetiological Cause of Rheumatoid Arthritis: What Are the Unsolved Puzzles?

Toxins ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 50
Author(s):  
Sung Cheng Looh ◽  
Zoey May Pheng Soo ◽  
Jia Jia Wong ◽  
Hok Chai Yam ◽  
Sook Khuan Chow ◽  
...  

Leukotoxin A (LtxA) is the major virulence factor of an oral bacterium known as Aggregatibacter actinomycetemcomitans (Aa). LtxA is associated with elevated levels of anti-citrullinated protein antibodies (ACPA) in rheumatoid arthritis (RA) patients. LtxA targets leukocytes and triggers an influx of extracellular calcium into cytosol. The current proposed model of LtxA-mediated hypercitrullination involves the dysregulated activation of peptidylarginine deiminase (PAD) enzymes to citrullinate proteins, the release of hypercitrullinated proteins through cell death, and the production of autoantigens recognized by ACPA. Although model-based evidence is yet to be established, its interaction with the host’s immune system sparked interest in the role of LtxA in RA. The first part of this review summarizes the current knowledge of Aa and LtxA. The next part highlights the findings of previous studies on the association of Aa or LtxA with RA aetiology. Finally, we discuss the unresolved aspects of the proposed link between LtxA of Aa and RA.

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Qingfei Chu ◽  
Xinyu Gu ◽  
Qiuxian Zheng ◽  
Jing Wang ◽  
Haihong Zhu

In addition to playing a pivotal role in cellular energetics and biosynthesis, mitochondrial components are key operators in the regulation of cell death. In addition to apoptosis, necrosis is a highly relevant form of programmed liver cell death. Differential activation of specific forms of programmed cell death may not only affect the outcome of liver disease but may also provide new opportunities for therapeutic intervention. This review describes the role of mitochondria in cell death and the mechanism that leads to chronic liver hepatitis and liver cirrhosis. We focus on mitochondrial-driven apoptosis and current knowledge of necroptosis and discuss therapeutic strategies for targeting mitochondrial-mediated cell death in liver diseases.


2013 ◽  
Vol 66 (1) ◽  
pp. 40-48 ◽  
Author(s):  
Masaru Kato ◽  
Caroline Ospelt ◽  
Renate E. Gay ◽  
Steffen Gay ◽  
Kerstin Klein

Nutrients ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 3155 ◽  
Author(s):  
Mrinalini Dey ◽  
Maurizio Cutolo ◽  
Elena Nikiphorou

Background: The role of nutrition in the pathogenesis of rheumatic diseases, including rheumatoid arthritis (RA), has gained increasing attention in recent years. A growing number of studies have focussed on the diverse nutritional contents of beverages, and their possible role in the development and progression of RA. Main body: We aimed to summarise the current knowledge on the role of a range of beverages in the context of RA. Beverages have a key role within the mosaic of autoimmunity in RA and potential to alter the microbiome, leading to downstream effects on inflammatory pathways. The molecular contents of beverages, including coffee, tea, and wine, have similarly been found to interfere with immune signalling pathways, some beneficial for disease progression and others less so. Finally, we consider beverages in the context of wider dietary patterns, and how this growing body of evidence may be harnessed by the multidisciplinary team in patient management. Conclusions: While there is increasing work focussing on the role of beverages in RA, integration of discussions around diet and lifestyle in our management of patients remains sparse. Nutrition in RA remains a controversial topic, but future studies, especially on the role of beverages, are likely to shed further light on this in coming years.


2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Samuel García ◽  
Carmen Conde

Poly(ADP-ribose) polymerase-1 (PARP-1) is a nuclear enzyme with a crucial role in the maintenance of genomic stability. In addition to the role of PARP-1 in DNA repair, multiple studies have also demonstrated its involvement in several inflammatory diseases, such as septic shock, asthma, atherosclerosis, and stroke, as well as in cancer. In these diseases, the pharmacological inhibition of PARP-1 has shown a beneficial effect, suggesting that PARP-1 regulates their inflammatory processes. In recent years, we have studied the role of PARP-1 in rheumatoid arthritis, as have other researchers, and the results have shown that PARP-1 has an important function in the development of this disease. This review summarizes current knowledge on the effects of PARP-1 in rheumatoid arthritis.


2017 ◽  
Vol 42 (4) ◽  
pp. 390-398 ◽  
Author(s):  
Weronika Kurowska ◽  
Ewa H. Kuca-Warnawin ◽  
Anna Radzikowska ◽  
Włodzimierz Maśliński

2005 ◽  
Vol 2005 (3) ◽  
pp. 121-130 ◽  
Author(s):  
Anna Maria Witkowska

A soluble IL-2 receptor (sIL-2R) is a circulating form of a membrane receptor localized on lymphoid and some cancer cells. The biological function of sIL-2R has not been completely understood. Substantially, it seems to reflect T-lymphocyte activation in diseases of different pathology. Moreover, the soluble receptor has been considered, at least in part, responsible for unsuccessful immunotherapy with IL-2 in cancers. Several lines of evidence indicate sIL-2R measurements to be useful in determining disease progress and prognosis. This review summarizes current knowledge on the sIL-2R behavior in RA and solid cancers of varied etiology.


Author(s):  
Lourdes Rey ◽  
Sergio Mérida-López ◽  
Nicolás Sánchez-Álvarez ◽  
Natalio Extremera

This study contributes to current knowledge on the protective role of emotional intelligence and flourishing in cases of suicide risk (namely depressive symptoms and suicidal ideation) in a sample of adolescent victims of traditional bullying. The proposed model tested the mediator role of flourishing in the relationship between emotional intelligence (EI) and suicide risk together with the moderating effect of EI in the relationship between low flourishing and increased suicide risk. Considering an initial sample of 1847 adolescents (52.5% female), a subsample of 494 pure bullying victims (61.3% female) took part in this research. The main results showed EI to be linked to decreased suicide risk through levels of flourishing. Moreover, EI buffered the relationship between low flourishing and the associated suicide risk. Victimized adolescents with both low levels of EI and of flourishing reported higher levels of suicide risk than their counterparts with high EI levels. This suggests the protective role of EI of both predicting higher flourishing and reducing the likelihood of suicide risk among victimized adolescents with low levels of flourishing. Finally, the practical implications of these novel findings regarding the role of EI and flourishing in the prevention of suicide risk among victimized adolescents are discussed.


2013 ◽  
Vol 72 (Suppl 3) ◽  
pp. A807.2-A807
Author(s):  
M. Kato ◽  
C. Ospelt ◽  
B. A. Michel ◽  
R. E. Gay ◽  
S. Gay ◽  
...  

2008 ◽  
Vol 2008 ◽  
pp. 1-6 ◽  
Author(s):  
Seung-Ah Yoo ◽  
Seung-Ki Kwok ◽  
Wan-Uk Kim

Recent experimental and clinical studies have placed new emphasis on the role of angiogenesis in chronic inflammatory disease. Vascular endothelial growth factor (VEGF) and its receptors are the best characterized system in the regulation of rheumatoid arthritis (RA) by angiogenesis. Furthermore, in addition to its angiogenic role, VEGF can act as a direct proinflammatory mediator during the pathogenesis of RA, and protect rheumatoid synoviocytes from apoptosis, which contributes to synovial hyperplasia. Therefore, the developments of synovial inflammation, hyperplasia, and angiogenesis in the joints of RA patients seem to be regulated by a common cue, namely, VEGF. Agents that target VEGF, such as anti-VEGF antibody and aptamer, have yielded promising clinical data in patients with cancer or macular degeneration, and in RA patients, pharmacologic modulations targeting VEGF or its receptor may offer new therapeutic approaches. In this review, the authors integrate current knowledge of VEGF signaling and information on VEGF antagonists gleaned experimentally and place emphasis on the use of synthetic anti-VEGF hexapeptide to prevent VEGF interacting with its receptor.


Sign in / Sign up

Export Citation Format

Share Document