scholarly journals Protein Quality Evaluation of Animal Food Proteins by <i>In-Vitro</i> Methodologies

2013 ◽  
Vol 04 (04) ◽  
pp. 376-384 ◽  
Author(s):  
Jesús Manuel Barrón-Hoyos ◽  
Adrian Rafael Archuleta ◽  
María del Refugio Falcón-Villa ◽  
Rafael Canett-Romero ◽  
Francisco Javier Cinco-Moroyoqui ◽  
...  
2012 ◽  
Vol 108 (S2) ◽  
pp. S149-S157 ◽  
Author(s):  
Kay J. Rutherfurd-Markwick

In addition to supplying essential nutrients, some food proteins can confer additional health benefits beyond nutrition. The presence of bioactive proteins and peptides in different foods is a factor not currently taken into consideration when assessing the dietary quality of food proteins. The range of described physiological benefits attributed to bioactive proteins and peptides is diverse. Multiple factors can potentially impact on the ability of a bioactive peptide or protein to elicit an effect. Although some food proteins act directly in their intact form to elicit their effects, generally it is peptides derived from digestion, hydrolysis or fermentation that are of most interest. The levels of bioactive peptides generated must be sufficient to elicit a response, but should not be so high as to be unsafe, thus causing negative effects. In addition, some peptides cause systemic effects and therefore must be absorbed, again in sufficient amounts to elicit their action. Many studies to date have been carried outin vitro; therefore it is important that further trials are conductedin vivoto assess efficacy, dose response and safety of the peptides, particularly if health related claims are to be made. Therefore, methods must be developed and standardised that enable the measurement of health benefits and also the level of bioactive peptides which are absorbed into the bloodstream. Once standardised, such methods may provide a new perspective and an additional mechanism for analysing protein quality which is currently not encompassed by the use of the protein digestibility-corrected amino acid score (PDCAAS).


2002 ◽  
Vol 7 (3) ◽  
pp. 287-292 ◽  
Author(s):  
Eun-Young Hwang ◽  
Jin-Hwa Lee ◽  
Hong-Soo Ryu ◽  
Nam-Gyu Park ◽  
Soon-Sil Chun

Biomolecules ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 110
Author(s):  
Dina Aweida ◽  
Shenhav Cohen

Protein degradation maintains cellular integrity by regulating virtually all biological processes, whereas impaired proteolysis perturbs protein quality control, and often leads to human disease. Two major proteolytic systems are responsible for protein breakdown in all cells: autophagy, which facilitates the loss of organelles, protein aggregates, and cell surface proteins; and the ubiquitin-proteasome system (UPS), which promotes degradation of mainly soluble proteins. Recent findings indicate that more complex protein structures, such as filamentous assemblies, which are not accessible to the catalytic core of the proteasome in vitro, can be efficiently degraded by this proteolytic machinery in systemic catabolic states in vivo. Mechanisms that loosen the filamentous structure seem to be activated first, hence increasing the accessibility of protein constituents to the UPS. In this review, we will discuss the mechanisms underlying the disassembly and loss of the intricate insoluble filamentous myofibrils, which are responsible for muscle contraction, and whose degradation by the UPS causes weakness and disability in aging and disease. Several lines of evidence indicate that myofibril breakdown occurs in a strictly ordered and controlled manner, and the function of AAA-ATPases is crucial for their disassembly and loss.


1998 ◽  
Vol 22 ◽  
pp. 120-122
Author(s):  
A. S. Chaudhry

The need to develop an in vitro method to simulate ruminal digestion of protein foods has long been recognized. An in vitro method must be more rapid, consistent and convenient than in sacco methods. Purified enzymes have been examined in the past to estimate in vitro degradability of protein foods (Poos-Floyd et al., 1985; Aufrere et al., 1991; Luchini et al., 1996) or their fractions (Chaudhry and Webster, 1994). However, the selection of an appropriate enzyme for a range of foodstuffs remains to be realized. This study examined the potential of two enzymes and a centrifuged rumen fluid (CRF) to estimate proteolysis of food proteins.


2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Shirin Doroudgar ◽  
Mirko Völkers ◽  
Donna J Thuerauf ◽  
Ashley Bumbar ◽  
Mohsin Khan ◽  
...  

The endoplasmic reticulum (ER) is essential for protein homeostasis, or proteostasis, which governs the balance of the proteome. In addition to secreted and membrane proteins, proteins bound for many other cellular locations are also made on ER-bound ribosomes, emphasizing the importance of protein quality and quantity control in the ER. Unlike cytosolic E3 ubiquitin ligases studied in the heart, synoviolin/Hrd1, which has not been studied in the heart, is an ER transmembrane E3 ubiquitin ligase, which we found to be upregulated upon protein misfolding in cardiac myocytes. Given the strategic location of synoviolin in the ER membrane, we addressed the hypothesis that synoviolin is critical for regulating the balance of the proteome, and accordingly, myocyte size. We showed that in vitro, adenovirus-mediated overexpression of synoviolin decreased cardiac myocyte size and protein synthesis, but unlike atrophy-related ubiquitin ligases, synoviolin did not increase global protein degradation. Furthermore, targeted gene therapy using adeno-associated virus 9 (AAV9) showed that overexpression of synoviolin in the left ventricle attenuated maladaptive cardiac hypertrophy and preserved cardiac function in mice subjected to trans-aortic constriction (AAV9-control TAC = 22.5 ± 6.2% decrease in EF vs. AAV9-synoviolin TAC at 6 weeks post TAC; P<0.001), and decreased mTOR activity. Since calcium is a major regulator of cardiac myocyte size, we examined the effects of synoviolin gain- or loss-of-function, using AAV9-synoviolin, or an miRNA designed to knock down synoviolin, respectively. While synoviolin gain-of-function did not affect calcium handling in isolated adult myocytes, synoviolin loss-of-function increased calcium transient amplitude (P<0.01), prolonged spark duration (P<0.001), and increased spark width (P<0.001). Spark frequency and amplitude were unaltered upon synoviolin gain- or loss-of-function. Whereas SR calcium load was unaltered by synoviolin loss-of-function, SERCA-mediated calcium removal was reduced (P<0.05). In conclusion, our studies suggest that in the heart, synoviolin is 1) a critical component of proteostasis, 2) a novel determinant of cardiac myocyte size, and 3) necessary for proper calcium handling.


2005 ◽  
Vol 25 (6) ◽  
pp. 587-596 ◽  
Author(s):  
Sahadevan Seena ◽  
Kandikere R. Sridhar ◽  
Saraf R. Ramesh

2019 ◽  
Vol 3 (2) ◽  
pp. 30-35
Author(s):  
Karen N. Dartora ◽  
Paula C. Bona ◽  
Francielli L. Dos Santos ◽  
Paula Bianchetti ◽  
Renata Vidor Contri

The objective of this study was to evaluate quality parameters of magistral topical solutions containing minoxidil (A, B and C), comparing the results with the ones obtained for the industrial formulation. Organoleptic tests, evaluation of the pH and density, centrifuge test, drug content determination, comparison of indicated dosages and in vitro follicular penetration of minoxidil were performed. Regarding the organoleptic properties, differences in color and viscosity were observed between the magistral (composed of minoxidil sulfate) and the industrial formulations (composed of minoxidil base). For pH values, the magistral solutions presented considerably more acidic pH, compared to the industrial sample. For the density test, the samples with the highest ethanol percentages (B and C) presented lower density. In the centrifuge test, none of the samples showed changes. Considering the drug content test, only the industrial sample and the magistral sample C showed drug percentage within the expected (90-110%), indicating lack of correction factor determination by the magistral pharmacies. Furthermore, it was observed that the dosage indicated by the magistral pharmacies do not correspond to the dose indicated by the industry, being significantly lower. All topical solutions tested presented hair follicle penetration of minoxildil, without statistical difference. The results indicate that there is a failure in the magistral pharmacies regarding the production and the indication of dosage of minoxidil topical solutions.


2019 ◽  
Author(s):  
Aida Revilla-García ◽  
Cristina Fernández ◽  
María Moreno-del Álamo ◽  
Vivian de los Ríos ◽  
Ina M. Vorberg ◽  
...  

AbstractRepA is a bacterial protein that builds intracellular amyloid oligomers acting as inhibitory complexes of plasmid DNA replication. When carrying a mutation enhancing its amyloidogenesis (A31V), the N-terminal domain (WH1) generates cytosolic amyloid particles that are inheritable within a bacterial lineage. Such amyloids trigger in bacteria a lethal cascade reminiscent to mitochondria impairment in human cells affected by neurodegeneration. To fulfil all the features of a prion-like protein, horizontal (intercellular) transmissibility remains to be demonstrated for RepA-WH1. Since this is experimentally intractable in bacteria, here we transiently expressed in a murine neuroblastoma cell line the soluble, barely cytotoxic RepA-WH1(WT) and assayed its response to co-incubation with in vitro assembled RepA-WH1(A31V) amyloid fibres. In parallel, cells releasing RepA-WH1(A31V) aggregates were co-cultured with human neuroblastoma cells expressing RepA-WH1(WT). Both the assembled fibres and the extracellular RepA-WH1(A31V) aggregates induce, in the cytosol of recipient cells, the formation of cytotoxic amyloid particles. Mass spectrometry analyses of the proteomes of both types of injured cells point to alterations in mitochondria, protein quality triage, signalling and intracellular traffic.Summary blurbThe horizontal, cell-to-cell spread of a bacterial prion-like protein is shown for the first time in mammalian cells. Amyloid cross-aggregation of distinct variants, and their associated toxicities, follow the same trend found in bacteria, underlining the universality of prion biology.


Author(s):  
Nijsiri Ruangrungsi ◽  
Yamon Pitakpawasutthi ◽  
Maneewan Suwatronnakorn ◽  
Somchai Issaravanich ◽  
Chanida Palanuvej

Sign in / Sign up

Export Citation Format

Share Document