Mini Review | DOI: https://doi.org/10.31579/2690-4861/019

Heparin and Amyloid ?2-Microglobulin

  • Yuichiro Higashimoto 1
  • Tatsuo Yoneda 2
  • Yoshihiro Motomiya 3*
  • 1 Department of Chemistry, Kurume University School of Medicine, Kurume, Fukuoka, Japan
  • 2 Department of Urology, Nara Medical University, Japan
  • 3* Suiyukai Clinic, Kashihara, Nara, Japan

*Corresponding Author: Yoshihiro Motomiya, Suiyukai Clinic, Kashihara, Nara, Japan

Citation: Higashimoto Y., Yoneda T., Motomiya Y. (2020) Mini-review: Heparin and Amyloid β2-Microglobulin. International Journal of Clinical Case Reports and Reviews. 2(2); DOI:10.31579/2690-4861/019

Copyright: © 2020 Yoshihiro Motomiya, This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Received: 20 March 2020 | Accepted: 17 April 2020 | Published: 27 April 2020

Keywords: glycosaminoglycans; hemodialysis; microglobulin

Abstract

Heparin is a major component of glycosaminoglycans (GAGs), which are components of tissues in the interstitial spaces of the body. Heparin is the most important anticoagulant used in clinical settings, especially for hemodialysis (HD).

Introduction

Heparin is a major component of glycosaminoglycans (GAGs), which are components of tissues in the interstitial spaces of the body. Heparin is the most important anticoagulant used in clinical settings, especially for hemodialysis (HD).

Since Gejo’s report in 1985, β2-microglobulin (β2-M) has been recognized as the precursor protein in dialysis-related amyloidosis (DRA), which is inevitably associated with long-term HD [1]. In general, this amyloidosis develops in the presence of two essential background conditions, i.e., extremely high concentrations of precursor proteins and amyloidogenic conformation of these precursor proteins. Connors [2] first demonstrated the amyloidogenic potential of β2-M in 1985. Serum β2-M levels in end-stage renal failure were known to be elevated because the kidney is the main organ related to the metabolism of β2-M. In addition, we later proved that the conversion of the native β2-M conformation to the amyloidogenic β2-M conformation was triggered by unfolding of the C-terminal portion from Ile-92 to Met-99 [3, 4] (Figure 1).

Figure1: C-terminal unfolding : destructuring by loss of intram

However, how native β2-M is converted to an amyloidogenic conformer with the unfolded C-terminus in vivo, i.e., in clinical settings such as HD, and how β2-M concentrations in the interstitial space reach as high as millimolar values despite micromolar serum levels of β2-M in patients with HD [5] have not been clarified. In this mini-review, we would like to demonstrate that heparin may be a key molecule for the answers to both of these questions.

Heparin is a mucopolysaccharide with different molecular weights (MWs) when prepared from animal organs, such as the intestine or the lung, and has been used widely as an anticoagulant. In the early 1990s, low-molecular-weight heparin (LMH), less than 6 kD, was introduced in HD to reduce the high risk of bleeding that had been associated with conventional heparin, which had heterogeneous MWs of more than 10 kD, or with high-molecular-weight heparin (HMH) [6]. Our previous study demonstrated a clear difference between HMH and LMH in interactions with β2-M, as follows [7].

Binding of Heparin with β2-M

HMH binds in a dose-dependent manner with DN6β2-M, a well-known highly amyloidogenic variant of β2-M [8]; binds somewhat with D76N β2-M, a natural amyloid variant of β2-M; and demonstrates weak binding with native β2-M (Figure 2).

Figure 2 Analysis of the interaction of β2m variants with high molecular weight heparin.

Biotinylated H.M.H. (0.5 U/mL) was immobilized onto streptavidin biosensor. Protein concentrations were 1.0 µM (A) and 0.1 µM (B), respectively. ΔN6β2m (line, ──), D76N β2m (dashed line, ----) and native β2m (dotted line,).

The kD values for each β2-M species were as follows: 2.07×10-8M, and 1.72×10-7M, 3.71×10-6M respectively. The kD value of DN6β2-M was low, consistent with that of its specific aptamer [7].

LMH, however, did not bind with DN6β2-M or native β2-M (Figure 3).

Figure 3 Analysis of the interaction of β2m variants with low molecular weight heparin.

Biotinylated L.M.H. (5.0 U/mL) was immobilized onto streptavidin biosensor. ΔN6β2m (line, ──) and native β2m (dotted line,) were used as the binding partner. Protein concentration was 4.0 µM.  The real time binding curves were used to compute equilibrium dissociation constant by globally fitting the rate equation for 1:1 kinetics to the data.  Three-independent experiments were performed, respectively.

Because GAGs in the interstitial space have a rich heparin component, β2-M has been trapped in the interstitial space and accumulated in a time-dependent fashion in patients undergoing HD, and their levels of β2-M are expected to reach as high as millimolar values in 10 years or more.

Unfolding of the C-terminus of the β2-M molecule

An intermediate molecule with a partially unfolded structure of precursor proteins was identified as a key molecule in the amyloidogenic process [10]. With regard to β2-M, we confirmed that the unfolding at the C-terminus from Ile-92 to Met-99 was key process for the initiation of amyloidogenicity of this precursor protein (Figures 1–3). Our study of heparin demonstrated that 1 μM HMH could trigger the C-terminal unfolding of β2-M, which was consistent with the serum concentrations of β2-M in patients undergoing HD (Figure 4) [7].

Figure 4 Analysis of the interaction of mAb92-99 with native β2m in the presence of H.M.H.

MAb92-99 (10 µg/mL) was immobilized onto protein a biosensor. After adding native β2m to the reaction drop holder in the presence or absence of H.M.H., the real-time binding was monitored.  Native β2m incubated with H.M.H. (0.5 U/mL) for 24 h was also used as the binding partner.

In addition, given that β2-M concentrations may be much higher in the interstitial space than are concentrations in serum, we may expect more unfolding at the N-terminus than the C-terminus, which is likely to undergo proteolysis at Lys-6 and generate a highly amyloidogenic variant, DN6β2-M [8], because the unfolding process is believed to proceed from the N-terminus of β2-M [11].

GAGs Contain a Majority of the SO3– Moiety

Chemical solvents containing SO3– such as sodium dodecyl sulfate have induced conformational changes in proteins. For β2-M, several studies indicated amyloidogenic conversion that depended on a majority of SO3– moieties being present in GAGs [12,13,14,15]. As is well-known, heparin is a highly negative mucopolysaccharide rich in the SO3– moiety. Although we had not studied the dose-dependent effect of heparin on the C-terminal unfolding of β2-M, we believe that the SO3– majority contained in heparin may affect the results for HMH and LMH. The conformation of the β2-Mmolecule is maintained by multiple intramolecular hydrogen bonds, which may be partially broken by multiple SO3− groups.

Conclusion

Collectively, our studies have indicated two actions of HMH with β2-M: direct binding and induction of C-terminal unfolding. The former may result in an accumulation of β2-M in the interstitial space and the latter may lead to β2-M amyloidogenicity.

LMH showed no clear interactions, even with DN6β2-M, which indicates a superior clinical availability compared with HMH as an anticoagulant during long-term HD, in which DRA is a serious complication.

References

Clearly Auctoresonline and particularly Psychology and Mental Health Care Journal is dedicated to improving health care services for individuals and populations. The editorial boards' ability to efficiently recognize and share the global importance of health literacy with a variety of stakeholders. Auctoresonline publishing platform can be used to facilitate of optimal client-based services and should be added to health care professionals' repertoire of evidence-based health care resources.

img

Virginia E. Koenig

Journal of Clinical Cardiology and Cardiovascular Intervention The submission and review process was adequate. However I think that the publication total value should have been enlightened in early fases. Thank you for all.

img

Delcio G Silva Junior

Journal of Women Health Care and Issues By the present mail, I want to say thank to you and tour colleagues for facilitating my published article. Specially thank you for the peer review process, support from the editorial office. I appreciate positively the quality of your journal.

img

Ziemlé Clément Méda

Journal of Clinical Research and Reports I would be very delighted to submit my testimonial regarding the reviewer board and the editorial office. The reviewer board were accurate and helpful regarding any modifications for my manuscript. And the editorial office were very helpful and supportive in contacting and monitoring with any update and offering help. It was my pleasure to contribute with your promising Journal and I am looking forward for more collaboration.

img

Mina Sherif Soliman Georgy

We would like to thank the Journal of Thoracic Disease and Cardiothoracic Surgery because of the services they provided us for our articles. The peer-review process was done in a very excellent time manner, and the opinions of the reviewers helped us to improve our manuscript further. The editorial office had an outstanding correspondence with us and guided us in many ways. During a hard time of the pandemic that is affecting every one of us tremendously, the editorial office helped us make everything easier for publishing scientific work. Hope for a more scientific relationship with your Journal.

img

Layla Shojaie

The peer-review process which consisted high quality queries on the paper. I did answer six reviewers’ questions and comments before the paper was accepted. The support from the editorial office is excellent.

img

Sing-yung Wu

Journal of Neuroscience and Neurological Surgery. I had the experience of publishing a research article recently. The whole process was simple from submission to publication. The reviewers made specific and valuable recommendations and corrections that improved the quality of my publication. I strongly recommend this Journal.

img

Orlando Villarreal

Dr. Katarzyna Byczkowska My testimonial covering: "The peer review process is quick and effective. The support from the editorial office is very professional and friendly. Quality of the Clinical Cardiology and Cardiovascular Interventions is scientific and publishes ground-breaking research on cardiology that is useful for other professionals in the field.

img

Katarzyna Byczkowska

Thank you most sincerely, with regard to the support you have given in relation to the reviewing process and the processing of my article entitled "Large Cell Neuroendocrine Carcinoma of The Prostate Gland: A Review and Update" for publication in your esteemed Journal, Journal of Cancer Research and Cellular Therapeutics". The editorial team has been very supportive.

img

Anthony Kodzo-Grey Venyo

Testimony of Journal of Clinical Otorhinolaryngology: work with your Reviews has been a educational and constructive experience. The editorial office were very helpful and supportive. It was a pleasure to contribute to your Journal.

img

Pedro Marques Gomes

Dr. Bernard Terkimbi Utoo, I am happy to publish my scientific work in Journal of Women Health Care and Issues (JWHCI). The manuscript submission was seamless and peer review process was top notch. I was amazed that 4 reviewers worked on the manuscript which made it a highly technical, standard and excellent quality paper. I appreciate the format and consideration for the APC as well as the speed of publication. It is my pleasure to continue with this scientific relationship with the esteem JWHCI.

img

Bernard Terkimbi Utoo

This is an acknowledgment for peer reviewers, editorial board of Journal of Clinical Research and Reports. They show a lot of consideration for us as publishers for our research article “Evaluation of the different factors associated with side effects of COVID-19 vaccination on medical students, Mutah university, Al-Karak, Jordan”, in a very professional and easy way. This journal is one of outstanding medical journal.

img

Prof Sherif W Mansour

Dear Hao Jiang, to Journal of Nutrition and Food Processing We greatly appreciate the efficient, professional and rapid processing of our paper by your team. If there is anything else we should do, please do not hesitate to let us know. On behalf of my co-authors, we would like to express our great appreciation to editor and reviewers.

img

Hao Jiang

As an author who has recently published in the journal "Brain and Neurological Disorders". I am delighted to provide a testimonial on the peer review process, editorial office support, and the overall quality of the journal. The peer review process at Brain and Neurological Disorders is rigorous and meticulous, ensuring that only high-quality, evidence-based research is published. The reviewers are experts in their fields, and their comments and suggestions were constructive and helped improve the quality of my manuscript. The review process was timely and efficient, with clear communication from the editorial office at each stage. The support from the editorial office was exceptional throughout the entire process. The editorial staff was responsive, professional, and always willing to help. They provided valuable guidance on formatting, structure, and ethical considerations, making the submission process seamless. Moreover, they kept me informed about the status of my manuscript and provided timely updates, which made the process less stressful. The journal Brain and Neurological Disorders is of the highest quality, with a strong focus on publishing cutting-edge research in the field of neurology. The articles published in this journal are well-researched, rigorously peer-reviewed, and written by experts in the field. The journal maintains high standards, ensuring that readers are provided with the most up-to-date and reliable information on brain and neurological disorders. In conclusion, I had a wonderful experience publishing in Brain and Neurological Disorders. The peer review process was thorough, the editorial office provided exceptional support, and the journal's quality is second to none. I would highly recommend this journal to any researcher working in the field of neurology and brain disorders.

img

Dr Shiming Tang

Dear Agrippa Hilda, Journal of Neuroscience and Neurological Surgery, Editorial Coordinator, I trust this message finds you well. I want to extend my appreciation for considering my article for publication in your esteemed journal. I am pleased to provide a testimonial regarding the peer review process and the support received from your editorial office. The peer review process for my paper was carried out in a highly professional and thorough manner. The feedback and comments provided by the authors were constructive and very useful in improving the quality of the manuscript. This rigorous assessment process undoubtedly contributes to the high standards maintained by your journal.

img

Raed Mualem

International Journal of Clinical Case Reports and Reviews. I strongly recommend to consider submitting your work to this high-quality journal. The support and availability of the Editorial staff is outstanding and the review process was both efficient and rigorous.

img

Andreas Filippaios

Thank you very much for publishing my Research Article titled “Comparing Treatment Outcome Of Allergic Rhinitis Patients After Using Fluticasone Nasal Spray And Nasal Douching" in the Journal of Clinical Otorhinolaryngology. As Medical Professionals we are immensely benefited from study of various informative Articles and Papers published in this high quality Journal. I look forward to enriching my knowledge by regular study of the Journal and contribute my future work in the field of ENT through the Journal for use by the medical fraternity. The support from the Editorial office was excellent and very prompt. I also welcome the comments received from the readers of my Research Article.

img

Dr Suramya Dhamija

Dear Erica Kelsey, Editorial Coordinator of Cancer Research and Cellular Therapeutics Our team is very satisfied with the processing of our paper by your journal. That was fast, efficient, rigorous, but without unnecessary complications. We appreciated the very short time between the submission of the paper and its publication on line on your site.

img

Bruno Chauffert

I am very glad to say that the peer review process is very successful and fast and support from the Editorial Office. Therefore, I would like to continue our scientific relationship for a long time. And I especially thank you for your kindly attention towards my article. Have a good day!

img

Baheci Selen

"We recently published an article entitled “Influence of beta-Cyclodextrins upon the Degradation of Carbofuran Derivatives under Alkaline Conditions" in the Journal of “Pesticides and Biofertilizers” to show that the cyclodextrins protect the carbamates increasing their half-life time in the presence of basic conditions This will be very helpful to understand carbofuran behaviour in the analytical, agro-environmental and food areas. We greatly appreciated the interaction with the editor and the editorial team; we were particularly well accompanied during the course of the revision process, since all various steps towards publication were short and without delay".

img

Jesus Simal-Gandara

I would like to express my gratitude towards you process of article review and submission. I found this to be very fair and expedient. Your follow up has been excellent. I have many publications in national and international journal and your process has been one of the best so far. Keep up the great work.

img

Douglas Miyazaki

We are grateful for this opportunity to provide a glowing recommendation to the Journal of Psychiatry and Psychotherapy. We found that the editorial team were very supportive, helpful, kept us abreast of timelines and over all very professional in nature. The peer review process was rigorous, efficient and constructive that really enhanced our article submission. The experience with this journal remains one of our best ever and we look forward to providing future submissions in the near future.

img

Dr Griffith

I am very pleased to serve as EBM of the journal, I hope many years of my experience in stem cells can help the journal from one way or another. As we know, stem cells hold great potential for regenerative medicine, which are mostly used to promote the repair response of diseased, dysfunctional or injured tissue using stem cells or their derivatives. I think Stem Cell Research and Therapeutics International is a great platform to publish and share the understanding towards the biology and translational or clinical application of stem cells.

img

Dr Tong Ming Liu

I would like to give my testimony in the support I have got by the peer review process and to support the editorial office where they were of asset to support young author like me to be encouraged to publish their work in your respected journal and globalize and share knowledge across the globe. I really give my great gratitude to your journal and the peer review including the editorial office.

img

Husain Taha Radhi

I am delighted to publish our manuscript entitled "A Perspective on Cocaine Induced Stroke - Its Mechanisms and Management" in the Journal of Neuroscience and Neurological Surgery. The peer review process, support from the editorial office, and quality of the journal are excellent. The manuscripts published are of high quality and of excellent scientific value. I recommend this journal very much to colleagues.

img

S Munshi

Dr.Tania Muñoz, My experience as researcher and author of a review article in The Journal Clinical Cardiology and Interventions has been very enriching and stimulating. The editorial team is excellent, performs its work with absolute responsibility and delivery. They are proactive, dynamic and receptive to all proposals. Supporting at all times the vast universe of authors who choose them as an option for publication. The team of review specialists, members of the editorial board, are brilliant professionals, with remarkable performance in medical research and scientific methodology. Together they form a frontline team that consolidates the JCCI as a magnificent option for the publication and review of high-level medical articles and broad collective interest. I am honored to be able to share my review article and open to receive all your comments.

img

Tania Munoz

“The peer review process of JPMHC is quick and effective. Authors are benefited by good and professional reviewers with huge experience in the field of psychology and mental health. The support from the editorial office is very professional. People to contact to are friendly and happy to help and assist any query authors might have. Quality of the Journal is scientific and publishes ground-breaking research on mental health that is useful for other professionals in the field”.

img

George Varvatsoulias

Dear editorial department: On behalf of our team, I hereby certify the reliability and superiority of the International Journal of Clinical Case Reports and Reviews in the peer review process, editorial support, and journal quality. Firstly, the peer review process of the International Journal of Clinical Case Reports and Reviews is rigorous, fair, transparent, fast, and of high quality. The editorial department invites experts from relevant fields as anonymous reviewers to review all submitted manuscripts. These experts have rich academic backgrounds and experience, and can accurately evaluate the academic quality, originality, and suitability of manuscripts. The editorial department is committed to ensuring the rigor of the peer review process, while also making every effort to ensure a fast review cycle to meet the needs of authors and the academic community. Secondly, the editorial team of the International Journal of Clinical Case Reports and Reviews is composed of a group of senior scholars and professionals with rich experience and professional knowledge in related fields. The editorial department is committed to assisting authors in improving their manuscripts, ensuring their academic accuracy, clarity, and completeness. Editors actively collaborate with authors, providing useful suggestions and feedback to promote the improvement and development of the manuscript. We believe that the support of the editorial department is one of the key factors in ensuring the quality of the journal. Finally, the International Journal of Clinical Case Reports and Reviews is renowned for its high- quality articles and strict academic standards. The editorial department is committed to publishing innovative and academically valuable research results to promote the development and progress of related fields. The International Journal of Clinical Case Reports and Reviews is reasonably priced and ensures excellent service and quality ratio, allowing authors to obtain high-level academic publishing opportunities in an affordable manner. I hereby solemnly declare that the International Journal of Clinical Case Reports and Reviews has a high level of credibility and superiority in terms of peer review process, editorial support, reasonable fees, and journal quality. Sincerely, Rui Tao.

img

Rui Tao

Clinical Cardiology and Cardiovascular Interventions I testity the covering of the peer review process, support from the editorial office, and quality of the journal.

img

Khurram Arshad