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Meat Science Apr 2020This review aimed to examine the literature about blooming to determine any practical implications for meat colour and colour stability. Blooming is critical to surface... (Review)
Review
This review aimed to examine the literature about blooming to determine any practical implications for meat colour and colour stability. Blooming is critical to surface colour in addition to pigment and achromatic factors and causes meat to become lighter (higher L*) and redder (higher a*) due to the formation of oxymyoglobin (OMb). Bloom depth of red meat varies in the range of about 1-12 mm due to a range of extrinsic factors notably oxygen partial pressure, temperature and time post slicing. A range of intrinsic factors also affect bloom acting via the oxygen consumption rate of mitochondria and metmyoglobin (MMb) reductase activity post mortem, such as post mortem age, muscle type, rigor temperature, ultimate pH (pHu), genotype and vitamin E status. These sources of variation have implications for measurement protocols and commercial applications for colour and colour stability. Development of a rapid method to measure bloom depth would enable assessment of bloom independently of surface colour.
Topics: Animals; Color; Mitochondria; Myoglobin; NADH, NADPH Oxidoreductases; Oxygen; Oxygen Consumption; Red Meat; Temperature
PubMed: 31927436
DOI: 10.1016/j.meatsci.2019.108040 -
JCI Insight Oct 2022BACKGROUNDDuring aging, there is a functional decline in the pool of muscle stem cells (MuSCs) that influences the functional and regenerative capacity of skeletal... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUNDDuring aging, there is a functional decline in the pool of muscle stem cells (MuSCs) that influences the functional and regenerative capacity of skeletal muscle. Preclinical evidence has suggested that nicotinamide riboside (NR) and pterostilbene (PT) can improve muscle regeneration, e.g., by increasing MuSC function. The objective of this study was to investigate if supplementation with NR and PT (NRPT) promotes skeletal muscle regeneration after muscle injury in elderly individuals by improved recruitment of MuSCs.METHODSThirty-two elderly individuals (55-80 years of age) were randomized to daily supplementation with either NRPT (1,000 mg NR and 200 mg PT) or matched placebo. Two weeks after initiation of supplementation, skeletal muscle injury was induced by electrically induced eccentric muscle work. Skeletal muscle biopsies were obtained before, 2 hours after, and 2, 8, and 30 days after injury.RESULTSA substantial skeletal muscle injury was induced by the protocol and associated with release of myoglobin and creatine kinase, muscle soreness, tissue edema, and a decrease in muscle strength. MuSC content, proliferation, and cell size revealed a large demand for recruitment after injury, but this was not affected by NRPT. Furthermore, histological analyses of muscle fiber area, central nuclei, and embryonic myosin heavy chain showed no NRPT supplementation effect.CONCLUSIONDaily supplementation with 1,000 mg NR and 200 mg PT is safe but does not improve recruitment of the MuSC pool or other measures of muscle recovery in response to injury or subsequent regeneration in elderly individuals.TRIAL REGISTRATIONClinicalTrials.gov NCT03754842.FUNDINGNovo Nordisk Foundation (NNF17OC0027242) and Novo Nordisk Foundation CBMR.
Topics: Aged; Creatine Kinase, MM Form; Dietary Supplements; Humans; Muscle, Skeletal; Muscular Diseases; Myoglobin; Myosin Heavy Chains; Niacinamide; Pyridinium Compounds; Stilbenes
PubMed: 35998039
DOI: 10.1172/jci.insight.158314 -
Nutrients Jul 2023This study investigated the acute effects of natural antioxidants, derived from yeast fermentation containing glutathione and dietary vitamin C supplementation, on... (Randomized Controlled Trial)
Randomized Controlled Trial
Enhancing Supplemental Effects of Acute Natural Antioxidant Derived from Yeast Fermentation and Vitamin C on Sports Performance in Triathlon Athletes: A Randomized, Double-Blinded, Placebo-Controlled, Crossover Trial.
This study investigated the acute effects of natural antioxidants, derived from yeast fermentation containing glutathione and dietary vitamin C supplementation, on metabolic function, skeletal muscle oxygenation, cardiac function, and antioxidant function during submaximal exercise in middle-aged triathlon athletes. Twelve participants (aged 49.42 ± 5.9 years) completed 90 min submaximal cycling trials corresponding to 70% maximal oxygen uptake with either vitamin C and glutathione (VitC+Glu), vitamin C (VitC), glutathione (Glu) supplementation, or placebo. Metabolic function (minute ventilation, oxygen uptake, carbon dioxide output [VCO], respiratory exchange ratio [RER], oxygen pulse [Opulse], carbohydrate oxidation, fat oxidation, and energy expenditure), skeletal muscle oxygenation (oxidized hemoglobin and myoglobin in skeletal muscle tissue, total hemoglobin and myoglobin in skeletal muscle tissue [tHb]), cardiac function (heart rate [HR], stroke volume [SV], cardiac output, end-diastolic volume, end-systolic volume, and ejection fraction), and antioxidant function parameters (blood lactate, superoxide dismutase, catalase, glutathione peroxidases, glutathione [GSH], diacron reactive oxygen metabolite [dROM], and biological antioxidant potential [BAP]) were measured during submaximal exercise and recovery. VCO, RER, HR, blood lactate after exercise, and dROM were significantly lower, and Opulse, tHb, and BAP were significantly higher for VitC+Glu than for the other trials ( < 0.05). In conclusion, combined vitamin C and glutathione supplementation was more effective in improving metabolic function, skeletal oxygenation, cardiac function, and antioxidant function during prolonged submaximal exercise in middle-aged triathletes.
Topics: Humans; Middle Aged; Antioxidants; Ascorbic Acid; Saccharomyces cerevisiae; Cross-Over Studies; Fermentation; Myoglobin; Vitamins; Athletic Performance; Glutathione; Muscle, Skeletal; Athletes; Oxygen; Lactates; Dietary Supplements
PubMed: 37571262
DOI: 10.3390/nu15153324 -
Meat Science Dec 2023Reduction in muscle glycogen triggered by adverse antemortem handling events alters postmortem energy metabolism and results in a high ultimate pH and dark, firm and dry...
Reduction in muscle glycogen triggered by adverse antemortem handling events alters postmortem energy metabolism and results in a high ultimate pH and dark, firm and dry beef, often referred to as 'dark-cutting'. However, the relationship between atypical dark (AT) beef, postmortem energy metabolism and underlying tissue characteristics remains somewhat unclear. Cattle harvested in the US and Canada representing normal (pH < 5.6), AT dark (pH 5.6-5.8) and dark cutting (DC; pH > 5.8) beef were analyzed for tissue characteristics related to energy metabolism. Results show AT dark beef is more oxidative but similar to normal beef in glycolytic potential and nucleotide abundance. Mitochondria DNA content (P < 0.05, Canada; P < 0.005, US) and oxidative enzymes for DC and AT dark beef were greater (P < 0.01; Canada and US) compared to normal beef. Myoglobin tracked (P < 0.01) with color classification. These findings show both DC and AT beef are inherently more oxidative and raise the possibility that more oxidative muscle may be more prone to develop dark beef.
Topics: Cattle; Animals; Muscle, Skeletal; Color; Myoglobin; Glycogen; Glycolysis; Hydrogen-Ion Concentration; Red Meat
PubMed: 37778129
DOI: 10.1016/j.meatsci.2023.109344 -
Biochemistry Sep 2023Proteins have undergone evolutionary processes to achieve optimal stability, increased functionality, and novel functions. Comparative analysis of existent and ancestral...
Proteins have undergone evolutionary processes to achieve optimal stability, increased functionality, and novel functions. Comparative analysis of existent and ancestral proteins provides insights into the factors that influence protein stability and function. Ancestral sequence reconstruction allows us to deduce the amino acid sequences of ancestral proteins. Here, we present the structural and functional characteristics of an ancestral protein, AncMH, reconstructed to be the last common ancestor of hemoglobins and myoglobins. Our findings reveal that AncMH harbors heme and that the heme binds oxygen. Furthermore, we demonstrate that the ferrous heme in AncMH is pentacoordinated, similar to that of human adult hemoglobin and horse myoglobin. A detailed comparison of the heme pocket structure indicates that the heme pocket in AncMH is more similar to that of hemoglobin than that of myoglobin. However, the autoxidation of AncMH is faster than that of both hemoglobin and myoglobin. Collectively, our results suggest that ancestral proteins of hemoglobins and myoglobins evolved in steps, including the hexa- to pentacoordination transition, followed by stabilization of the oxygen-bound form.
Topics: Adult; Humans; Animals; Horses; Globins; Heme; Myoglobin; Amino Acid Sequence; Oxygen
PubMed: 37647623
DOI: 10.1021/acs.biochem.3c00203 -
Pulse Duration Effects on Solution-Phase Protein Desorption in Laser Electrospray Mass Spectrometry.Journal of the American Society For... Apr 2023The effect of laser pulse duration on the ablation of aqueous myoglobin is investigated using laser electrospray mass spectrometry (LEMS). Pulse durations of 55...
The effect of laser pulse duration on the ablation of aqueous myoglobin is investigated using laser electrospray mass spectrometry (LEMS). Pulse durations of 55 femtoseconds (fs), 56 piscoseconds (ps), and 10 nanoseconds (ns) were used to ablate aqueous myoglobin from stainless-steel and quartz substrates. The integrated signal intensity of myoglobin increases with decreasing pulse duration for both substrates. Laser-induced thermal effects are assessed by the relative amount of solvent adduction and number of phosphate moieties adducted to myoglobin by each laser pulse duration. The mass spectra for 55 fs vaporization shows myoglobin with appreciable solvent and phosphate adduction and baseline elevation. The mass spectra for 10 ns ablation have minimal adduction and limited baseline elevation. Heat-induced conformation changes in myoglobin were used to measure the amount of thermal energy deposited by each laser pulse duration. Ablation using the 55 fs pulse revealed the highest ratio of unfolded to folded myoglobin in comparison to the 56 ps and 10 ns measurements due to increased droplet lifetime and consequent interaction with the acid in the electrospray solvent. Collisional activation and heated capillary temperature were employed to reduce the droplet lifetime and demonstrate that fs ablation preserves approximately 2 times more myoglobin folded conformation in comparison to ps and ns pulses.
Topics: Myoglobin; Spectrometry, Mass, Electrospray Ionization; Muramidase; Cytochromes c; Lasers; Solvents; Water
PubMed: 36947866
DOI: 10.1021/jasms.2c00362 -
Life Sciences Nov 2022Rhabdomyolysis is a life-threatening condition. One of the most common complications of rhabdomyolysis is acute kidney injury (AKI), and 10 % of all AKI patients...
AIMS
Rhabdomyolysis is a life-threatening condition. One of the most common complications of rhabdomyolysis is acute kidney injury (AKI), and 10 % of all AKI patients present with rhabdomyolysis. EGFR is associated with different types of AKI. However, the function and regulatory mechanism of EGFR in rhabdomyolysis-induced AKI model remain unknown. Here, we performed the experiments to explore the role of EGFR in this model.
MAIN METHODS
We used proximal tubule-specific Atg7 knockout mice and Wa-2 mice to establish animal models. Then, the samples were collected for pathology assay and IB detection. In vitro, the BUMPT cells treated with myoglobin were collected for the detection of apoptosis and autophagy. IB detection were processed for the analysis of protein expressions, FCM analysis for the cell apoptosis, GFP-LC3 transfection and immunofluorescent for autophagy.
KEY FINDINGS
EGFR promotes autophagy to mediate rhabdomyolysis-induced AKI via STAT3/Atg7 axis, and gefitinib is a potential therapeutic option for AKI. Here, we demonstrated that EGFR was activated by myoglobin and glycerol both in vitro and in vivo, respectively. Genetic or pharmacological inhibition of EGFR ameliorated myoglobin and glycerol-induced renal cell apoptosis. Mechanistically, EGFR mediated autophagy induction via STAT3/Atg7 axis, thereby resulting in kidney cell apoptosis. Furthermore, Wa-2 mice or gefitinib treatment prevented the progression of rhabdomyolysis-induced AKI as well as renal cell apoptosis and autophagy via inhibiting STAT3/Atg7 axis.
SIGNIFICANCE
Researchers can use this finding to better study the function and regulatory mechanism of EGFR in RM-induced AKI model. And gefitinib represents a potential target for treatment of AKI.
Topics: Mice; Animals; Myoglobin; Up-Regulation; Gefitinib; Glycerol; Rhabdomyolysis; Kidney; Acute Kidney Injury; Apoptosis; Autophagy; ErbB Receptors
PubMed: 36209831
DOI: 10.1016/j.lfs.2022.121050 -
Journal of Biological Inorganic... May 2020Myoglobin (Mb), generally taken as the molecular model of monomeric globular heme-proteins, is devoted: (i) to act as an intracellular oxygen reservoir, (ii) to...
Myoglobin (Mb), generally taken as the molecular model of monomeric globular heme-proteins, is devoted: (i) to act as an intracellular oxygen reservoir, (ii) to transport oxygen from the sarcolemma to the mitochondria of vertebrate heart and red muscle cells, and (iii) to act as a scavenger of nitrogen and oxygen reactive species protecting mitochondrial respiration. Here, the first evidence of NO inhibition of ferric Mb- (Mb(III)) mediated detoxification of peroxynitrite is reported, at pH 7.2 and 20.0 °C. NO binds to Mb(III) with a simple equilibrium; the value of the second-order rate constant for Mb(III) nitrosylation (i.e., k) is (6.8 ± 0.7) × 10 M s and the value of the first-order rate constant for Mb(III)-NO denitrosylation (i.e., k) is 3.1 ± 0.3 s. The calculated value of the dissociation equilibrium constant for Mb(III)-NO complex formation (i.e., k/k = (4.6 ± 0.7) × 10 M) is virtually the same as that directly measured (i.e., K = (3.8 ± 0.5) × 10 M). In the absence of NO, Mb(III) catalyzes the conversion of peroxynitrite to NO, the value of the second-order rate constant (i.e., k) being (1.9 ± 0.2) × 10 M s. However, in the presence of NO, Mb(III)-mediated detoxification of peroxynitrite is only partially inhibited, underlying the possibility that also Mb(III)-NO is able to catalyze the peroxynitrite isomerization, though with a reduced rate (k* = (2.8 ± 0.3) × 10 M s). These data expand the multiple roles of NO in modulating heme-protein actions, envisaging a delicate balancing between peroxynitrite and NO, which is modulated through the relative amount of Mb(III) and Mb(III)-NO.
Topics: Animals; Catalysis; Ferric Compounds; Free Radical Scavengers; Male; Molecular Structure; Myoglobin; Nitro Compounds; Peroxynitrous Acid; Whales
PubMed: 32172452
DOI: 10.1007/s00775-020-01767-2 -
Food & Function Aug 2022The study aimed to explore the digestion of a myoglobin diet and its relationship with the gut microbiota and intestinal barrier at two feeding time points. The study...
The study aimed to explore the digestion of a myoglobin diet and its relationship with the gut microbiota and intestinal barrier at two feeding time points. The study indicated that myoglobin diets had a higher α-helix content and lower digestibility. The particle sizes of the digested myoglobin diets were higher but their zeta potential values were lower than those of a casein diet. C57BL/6J mice were fed with a casein diet incorporated with 0, 0.38%, 1.13% and 3.39% myoglobin for 3 and 8 weeks. With the increase of the myoglobin content, the relative abundance of increased significantly. Moreover, the content of short chain fatty acids tended to increase and then decrease as the myoglobin content increased at 3 weeks. Furthermore, the low-myoglobin diet upregulated the gene expression involved in colonic mucin and tight junction proteins by increasing the proportion of beneficial microbiota. However, the high-myoglobin diet had adverse effects.
Topics: Animals; Caseins; Diet; Diet, High-Fat; Gastrointestinal Microbiome; Intestinal Mucosa; Mice; Mice, Inbred C57BL; Mucus; Myoglobin; Verrucomicrobia
PubMed: 35943300
DOI: 10.1039/d2fo01799g -
Journal of Inorganic Biochemistry Aug 2023Kinetic and structural investigations of the flavohemoglobin-type NO dioxygenase have suggested critical roles for transient Fe(III)O complex formation and O-forced...
Kinetic and structural investigations of the flavohemoglobin-type NO dioxygenase have suggested critical roles for transient Fe(III)O complex formation and O-forced movements affecting hydride transfer to the FAD cofactor and electron-transfer to the Fe(III)O complex. Stark-effect theory together with structural models and dipole and internal electrostatic field determinations provided a semi-quantitative spectroscopic method for investigating the proposed Fe(III)O complex and O-forced movements. Deoxygenation of the enzyme causes Stark effects on the ferric heme Soret and charge-transfer bands revealing the Fe(III)O complex. Deoxygenation also elicits Stark effects on the FAD that expose forces and motions that create a more restricted NADH access to FAD for hydride transfer and switch electron-transfer off. Glucose also forces the enzyme toward an off state. Amino acid substitutions at the B10, E7, E11, G8, D5, and F7 positions influence the Stark effects of O on resting heme spin states and FAD consistent with the proposed roles of the side chains in the enzyme mechanism. Deoxygenation of ferric myoglobin and hemoglobin A also induces Stark effects on the hemes suggesting a common 'oxy-met' state. The ferric myoglobin and hemoglobin heme spectra are also glucose-responsive. A conserved glucose or glucose-6-phosphate binding site is found bridging the BC-corner and G-helix in flavohemoglobin and myoglobin suggesting novel allosteric effector roles for glucose or glucose-6-phosphate in the NO dioxygenase and O storage functions. The results support the proposed roles of a ferric O intermediate and protein motions in regulating electron-transfer during NO dioxygenase turnover.
Topics: Iron; Myoglobin; Oxygen; Electrons; Glucose-6-Phosphate; Heme; Nitric Oxide
PubMed: 37229820
DOI: 10.1016/j.jinorgbio.2023.112257