scholarly journals Extension of the generic amyloid hypothesis to nonproteinaceous metabolite assemblies

2015 ◽  
Vol 1 (7) ◽  
pp. e1500137 ◽  
Author(s):  
Shira Shaham-Niv ◽  
Lihi Adler-Abramovich ◽  
Lee Schnaider ◽  
Ehud Gazit
Keyword(s):  
Metabolic Disorders ◽  
Amyloid Fibrils ◽  
Metabolic Diseases ◽  
Apoptotic Cell ◽  
Single Amino Acid ◽  
Amyloid Formation ◽  
Mice Model ◽  
General Phenomenon ◽  
New Paradigm ◽  
Proteins And Peptides

The accumulation of amyloid fibrils is the hallmark of several major human diseases. Although the formation of these supramolecular entities has previously been associated with proteins and peptides, it was later demonstrated that even phenylalanine, a single amino acid, can form fibrils that have amyloid-like biophysical, biochemical, and cytotoxic properties. Moreover, the generation of antibodies against these assemblies in phenylketonuria patients and the correlating mice model suggested a pathological role for the assemblies. We determine that several other metabolites that accumulate in metabolic disorders form ordered amyloid-like ultrastructures, which induce apoptotic cell death, as observed for amyloid structures. The formation of amyloid-like assemblies by metabolites implies a general phenomenon of amyloid formation, not limited to proteins and peptides, and offers a new paradigm for metabolic diseases.

scholarly journals Insights into the Structure of Amyloid Fibrils

2009 ◽  
Vol 2 (1) ◽  
pp. 185-192
Author(s):  
Karen E. Marshall ◽  
Louise C. Serpell
Keyword(s):  
Amyloid Fibrils ◽  
Amyloid Formation ◽  
X Ray Diffraction ◽  
Generic Structure ◽  
Structural Characterisation ◽  
Cryo Electron Microscopy ◽  
Atomic Interactions ◽  
Heterogeneous Nature ◽  
Structural Insights ◽  
Proteins And Peptides

Various proteins and peptides are able to self assemble into amyloid fibrils that are associated with disease. Structural characterisation of these fibres is limited by their insoluble and heterogeneous nature. However, advances in various techniques including X-ray diffraction, cryo-electron microscopy and solid state NMR have provided detailed information on various amyloid fibrils, from the long range order and macromolecular structure to the atomic interactions that promote assembly and stabilise the amyloid core. The cross-β model has been widely accepted as a generic structure for most amyloid fibrils and is discussed in detail. It is clear, however, that polymorphisms are present, even in fibrils formed from the same precursor protein, and that these may represent differences in packing at a molecular level. To fully understand the roles of particular residues in amyloid formation and structure, short peptides can be used in conjunction with mutagenesis studies to assess their effects. The structural insights gained using a combination of techniques to study both full-length, disease related peptides and short fragments are essential if progress is to be made towards understanding why these fibres form and how to prevent their formation.

IS IT POSSIBLE TO PREDICT AMYLOIDOGENIC REGIONS FROM SEQUENCE ALONE?

2006 ◽  
Vol 04 (02) ◽  
pp. 373-388 ◽  
Author(s):  
OXANA V. GALZITSKAYA ◽  
SERGIY O. GARBUZYNSKIY ◽  
MICHAIL YU. LOBANOV
Keyword(s):  
Amino Acid ◽  
Protein Sequence ◽  
Amyloid Fibrils ◽  
Amyloid Fibril ◽  
Fibril Formation ◽  
Amino Acid Sequences ◽  
Amyloid Formation ◽  
Amyloid Fibril Formation ◽  
Polypeptide Chains ◽  
Proteins And Peptides

Identification of potentially amyloidogenic regions in polypeptide chains is very important because the amyloid fibril formation can be induced in most normal proteins. In our work we suggest a new method to detect amyloidogenic regions in protein sequence. It is based on the assumption that packing is tight inside an amyloid and therefore regions which could potentially pack well would have a tendency to form amyloids. This means that the regions with strong expected packing of residues would be responsible for the amyloid formation. We use this property to identify potentially amyloidogenic regions in proteins basing on their amino acid sequences only. Our predictions are consistent with known disease-related amyloidogenic regions for 8 of 11 amyloid-forming proteins and peptides in which the positions of amyloidogenic regions have been revealed experimentally. Predictions of the regions which are responsible for the formation of amyloid fibrils in proteins unrelated to disease have been also done.

The Effects of Coenzyme Q10 Supplementation on Lipid Profiles Among Patients with Metabolic Diseases: A Systematic Review and Meta-analysis of Randomized Controlled Trials

2018 ◽  
Vol 24 (23) ◽  
pp. 2729-2742 ◽  
Author(s):  
Nasrin Sharifi ◽  
Reza Tabrizi ◽  
Mahmood Moosazadeh ◽  
Naghmeh Mirhosseini ◽  
Kamran B. Lankarani ◽  
...  
Keyword(s):  
Systematic Review ◽  
Lipid Profile ◽  
Coenzyme Q10 ◽  
Metabolic Disorders ◽  
Metabolic Diseases ◽  
Meta Analysis ◽  
Lipid Profiles ◽  
Controlled Trials ◽  
Serum Triglycerides ◽  
Coq10 Supplementation

Background and objective: Oxidative stress and inflammation are key parameters in developing metabolic disorders. Hence, antioxidant intake might be an appropriate approach. Several studies have evaluated the effect of coenzyme Q10 (CoQ10) supplementation on lipid profile among patients with metabolic diseases, though findings are controversial. The aim of this systematic review and meta-analysis was to determine the effects of CoQ10 supplementation on lipid profile in patients with metabolic disorders. Methods: We searched PubMed, EMBASE, Web of Science and Cochrane Library databases until July 2017. Prospective clinical trials were selected assessing the effect of CoQ10 supplementation on different biomarkers. Two reviewers independently assessed the eligibility of studies, extracted data, and evaluated the risk of bias of included studies. A fixed- or random-effects model was used to pool the data, which expressed as a standardized mean difference with 95% confidence interval. Heterogeneity was measured using a Q-test and with I2 statistics. Results: A total of twenty-one controlled trials (514 patients and 525 controls) were included. The meta-analysis indicated a significant reduction in serum triglycerides levels (SMD -0.28; 95% CI, -0.56, -0.005). CoQ10 supplementation also decreased total-cholesterol (SMD -0.07; 95% CI, -0.45, 0.31), increased LDL- (SMD 0.04; 95% CI, -0.27, 0.36), and HDL-cholesterol levels (SMD 0.10; 95% CI, -0.32, 0.51), not statistically significant. Conclusion: CoQ10 supplementation may significantly reduce serum triglycerides levels, and help to improve lipid profiles in patients with metabolic disorders. Additional prospective studies are recommended using higher supplementation doses and longer intervention period.

scholarly journals Apomorphine Targets the Pleiotropic Bacterial Regulator Hfq

Antibiotics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 257
Author(s):  
Florian Turbant ◽  
David Partouche ◽  
Omar El Hamoui ◽  
Sylvain Trépout ◽  
Théa Legoubey ◽  
...  
Keyword(s):  
Small Rnas ◽  
Antibacterial Agents ◽  
Amyloid Fibrils ◽  
Noncoding Rnas ◽  
Amyloid Formation ◽  
Gram Negative Bacteria ◽  
Translation Efficiency ◽  
Gram Negative ◽  
Bacterial Adaptation ◽  
E Coli

Hfq is a bacterial regulator with key roles in gene expression. The protein notably regulates translation efficiency and RNA decay in Gram-negative bacteria, thanks to its binding to small regulatory noncoding RNAs. This property is of primary importance for bacterial adaptation and survival in hosts. Small RNAs and Hfq are, for instance, involved in the response to antibiotics. Previous work has shown that the E. coli Hfq C-terminal region (Hfq-CTR) self-assembles into an amyloid structure. It was also demonstrated that the green tea compound EpiGallo Catechin Gallate (EGCG) binds to Hfq-CTR amyloid fibrils and remodels them into nonamyloid structures. Thus, compounds that target the amyloid region of Hfq may be used as antibacterial agents. Here, we show that another compound that inhibits amyloid formation, apomorphine, may also serve as a new antibacterial. Our results provide an alternative in order to repurpose apomorphine, commonly used in the treatment of Parkinson’s disease, as an antibiotic to block bacterial adaptation to treat infections.

scholarly journals Inhibition study of proinflammatory factor with ethanolic extract of propolis on innate immunity from diabetes mellitus mice model

2018 ◽  
Vol 90 (2) ◽  
Author(s):  
Bambang Pristiwanto ◽  
Sutiman B. Sumitro ◽  
Muhammad S. Djati ◽  
Aris Soewondo ◽  
Hideo Tsuboi ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Innate Immunity ◽  
Body Weight ◽  
Metabolic Diseases ◽  
Ethanolic Extract ◽  
Control Group ◽  
Mice Model ◽  
Innate Immunity Cells ◽  
Proinflammatory Factor ◽  
Ethanolic Extract Of Propolis

Health becomes an important topic today. One current problem was how to treat the effects of metabolic diseases, such as diabetes mellitus (DM). Thus, this study used an ethanolic extract of propolis (EEP), to test their ability as the supplement in the diabetes treatment to reduce inflammation, through proinflammatory factor response, especially nuclear factor κB (NF-κB). The streptozotocin- induced diabetes mellitus (SID) mice model was used, and expression of an proinflammatory factor was analyzed in their innate immunity cells with 3 doses of EEP, i.e. 50 mg/kg body weight, 100 mg/kg body weight, and 200 mg/kg body weight. Treatment of EEP in SID with three doses treatment decrease the number of macrophages with NF-κB expression significantly with DM control group. The results of B cells with NF-κB expression showed that EEP treatment in SID could decrease in dose 1 and dose 3, but not in dose 2. Proinflammatory cytokines expression of macrophage, especially Tumor Necrosis Factor-α and Interferon-γ, with EEP treatment in SID could decrease in three doses. This study suggests that EEP could reduce inflammation by inhibiting the development of NF-κB in innate immunity cells.

scholarly journals Identification of critical amino acid residues in the regulatory N-terminal domain of PMEL

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Susan M. Mitchell ◽  
Morven Graham ◽  
Xinran Liu ◽  
Ralf M. Leonhardt
Keyword(s):  
Amino Acid ◽  
Pigment Cell ◽  
Specific Protein ◽  
Single Amino Acid ◽  
Amyloid Formation ◽  
Amino Acid Residues ◽  
Proteolytic Fragment ◽  
The Core ◽  
N Terminus ◽  
In Cis

AbstractThe pigment cell-specific protein PMEL forms a functional amyloid matrix in melanosomes onto which the pigment melanin is deposited. The amyloid core consists of a short proteolytic fragment, which we have termed the core-amyloid fragment (CAF) and perhaps additional parts of the protein, such as the PKD domain. A highly O-glycosylated repeat (RPT) domain also derived from PMEL proteolysis associates with the amyloid and is necessary to establish the sheet-like morphology of the assemblies. Excluded from the aggregate is the regulatory N-terminus, which nevertheless must be linked in cis to the CAF in order to drive amyloid formation. The domain is then likely cleaved away immediately before, during, or immediately after the incorporation of a new CAF subunit into the nascent amyloid. We had previously identified a 21 amino acid long region, which mediates the regulatory activity of the N-terminus towards the CAF. However, many mutations in the respective segment caused misfolding and/or blocked PMEL export from the endoplasmic reticulum, leaving their phenotype hard to interpret. Here, we employ a saturating mutagenesis approach targeting the motif at single amino acid resolution. Our results confirm the critical nature of the PMEL N-terminal region and identify several residues essential for PMEL amyloidogenesis.

INHERITED METABOLIC DISORDERS AND HEART DISEASES

2019 ◽  
Author(s):  
Vjekoslav Krželj ◽  
Ivana Čulo Čagalj
Keyword(s):  
Metabolic Disorders ◽  
Metabolic Diseases ◽  
Technological Development ◽  
Heart Diseases ◽  
Glycogen Storage ◽  
Acid Oxidation ◽  
Lysosomal Storage ◽  
Glycogen Storage Diseases ◽  
Coronary Diseases ◽  
Inherited Metabolic Disorders

Inherited metabolic disorders can cause heart diseases, cardiomyopathy in particular, as well as cardiac arrhythmias, valvular and coronary diseases. More than 40 different inherited metabolic disorders can provoke cardiomyopathy, including lysosomal storage disorders, fatty acid oxidation defects, organic acidemias, amino acidopathies, glycogen storage diseases, congenital disorders of glycosylation as well as peroxisomal and mitochondrial disorders. If identified and diagnosed on time, some of congenital metabolic diseases could be successfully treated. It is important to assume them in cases when heart diseases are etiologically undefined. Rapid technological development has made it easier to establish the diagnosis of these diseases. This article will focus on common inherited metabolic disorders that cause heart diseases, as well as on diseases that might be possible to treat.

scholarly journals Ayurveda Internal Medicine for the Management of Common Metabolic Disorders W.S.R. to Madhumeha and Sthoulya

2019 ◽  
Vol 9 (5-s) ◽  
pp. 167-169
Author(s):  
Dhananjay S. Khot
Keyword(s):  
Internal Medicine ◽  
Metabolic Syndrome ◽  
Life Style ◽  
Metabolic Disorders ◽  
Dietary Habits ◽  
Metabolic Diseases ◽  
Health Issues ◽  
The Metabolic Syndrome ◽  
Sedentary Life Style

The metabolic disorders are major health issues of today’s scenario and incidences of metabolic diseases increases day by day due to the disturbed pattern of life style. Ayurveda texts have described term “Santarpanjanya Vikaras” which resembles diseases of defective tissue metabolism. Ayurveda mentioned that improper dietary habits and sedentary life style affects state of Agni which resulted Ama production and finally leading to the metabolic syndrome. The vitiation of Dosha, diminish state of Dhatu and blockage of channels, etc. also can initiate pathogenesis of metabolic disorders. The Kayachikitsa branch of Ayurveda recommended use of internal medicine for the management of various metabolic disorders. Considering increased health burden of society due to the metabolic syndrome present article explore role of ayurveda internal medicine for the management of metabolic syndrome. Keywords: Ayurveda, metabolic syndrome, Santarpanjanya, Madhumeha and Sthoulya.       

scholarly journals Deletion of Serf2 shifts amyloid conformation in an Aβ amyloid mouse model

2021 ◽  
Author(s):  
E. Stroo ◽  
L. Janssen ◽  
O. Sin ◽  
W. Hogewerf ◽  
M. Koster ◽  
...  
Keyword(s):  
Mouse Model ◽  
Amyloid Fibrils ◽  
Mammalian Brain ◽  
Amyloid Formation ◽  
List Type ◽  
Lung Maturation ◽  
Disease Manifestation ◽  
Aβ Amyloid ◽  
Perinatal Lethality

AbstractNeurodegenerative diseases like Alzheimer, Parkinson and Huntington disease are characterized by aggregation-prone proteins that form amyloid fibrils through a nucleation process. Despite the shared β-sheet structure, recent research has shown that structurally different polymorphs exist within fibrils of the same protein. These polymorphs are associated with varying levels of toxicity and different disease phenotypes. MOAG-4 and its human orthologs SERF1 and SERF2 have previously been shown to modify the nucleation and drive amyloid formation and protein toxicity in vitro and in C. elegans. To further explore these findings, we generated a Serf2 knockout (KO) mouse model and crossed it with the APPPS1 mouse model for Aβ amyloid pathology. Full-body KO of Serf2 resulted in a developmental delay and perinatal lethality due to insufficient lung maturation. Therefore, we proceeded with a brain-specific Serf2 KO, which was found to be viable. We examined the Aβ pathology at 1 and 3 months of age, which is before and after the start of amyloid deposition. We show that SERF2 deficiency does not affect the production and overall Aβ levels. Serf2 KO-APPPS1 mice displayed an increased intracellular Aβ accumulation at 1 month and a higher number of Aβ deposits compared to APPPS1 mice with similar Aβ levels. Moreover, conformation-specific dyes and electron microscopy revealed a difference in the structure and amyloid content of these Aβ deposits. Together, our results reveal that SERF2 causes a structural shift in Aβ aggregation in a mammalian brain. These findings indicate that a single endogenous factor may contribute to amyloid polymorphisms, allowing for new insights into this phenomenon’s contribution to disease manifestation.HighlightsLoss of SERF2 slows embryonic development and causes perinatal lethalitySERF2 affects proliferation in a cell-autonomous fashionBrain-specific Serf2 knockout does not affect viability or Aβ productionBrain deletion of Serf2 shifts the amyloid conformation of Aβ

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