Interaction of vitamin A supplementation level with ADH1C genotype on intramuscular fat in beef steers

Previously, the single nucleotide polymorphism in alcohol dehydrogenase (ADH1C c.-64T>C) was shown to have an association with intramuscular fat (IMF) in the longissimus thoracis (LT) muscle when vitamin A was limited in finishing rations of beef steers. The purpose of this study was to determine the optimum vitamin A supplementation level, in combination with ADH1C genotype, to increase IMF of the LT muscle. In total, 45 TT genotype, 45 CT and 27 CC Black Angus crossbred steers were backgrounded on a commercial ration containing 3360 IU vitamin A/kg dry matter (DM). During finishing, the steers were randomly assigned to one of three vitamin A treatments at 25%, 50% and 75% of the National Research Council recommendation of 2200 IU/kg DM. Treatments were administered via an oral bolus. Carcass quality was evaluated and a sample from the LT muscle was collected for analysis of IMF. A treatment×genotype interaction (P=0.04) was observed for IMF; TT steers on the 75% treatment had higher IMF relative to CT and CC steers on the same treatment. Western blot analysis showed that TT steers had higher (P=0.02) ADH1C protein expression in hepatic tissue. Previously, TT steers exhibited increased IMF when fed limited vitamin A. In the current study, the lack of variation in IMF between treatments and genotypes at the lower vitamin A treatment levels was likely due to the majority of the steers grading Canada AAA (USDA Choice). However, the western blot data supports that TT steers are expected to have higher IMF deposition, due to an increased production of ADH1C. The interaction between ADH1C genotype and vitamin A supplementation level has the potential for use in marker-assisted management programs to target niche markets based on increased marbling.     

Grape pomace improves performance,antioxidant status,fecal microbiota and meat quality of piglets

In the present study, grape pomace (GP) was used as feed additive in the diet of weaned piglets in order to develop innovative feedstuffs and to investigate their potential beneficial effects on welfare, productivity and meat quality. For examining the antioxidant capacity of the experimental feeds, 24 piglets of 20 days old were assigned to two experimental groups receiving standard or experimental diet for 30 days. Blood and tissues collections were performed at four different time-points, 2, 20, 35 and 50 days post birth. The collected tissues were brain, heart, kidney, liver, lung, quadriceps muscle, pancreas, spleen and stomach. The following oxidative stress markers were assessed: reduced glutathione (GSH), catalase activity, total antioxidant capacity (TAC), thiobarbituric acid reactive substances (TBARS), protein carbonyls (CARB) and H₂O₂ decomposition activity. The effect on bacterial growth was assessed by examining microbial populations in piglets’ fecal microbiota. Furthermore, the average daily gain (ADG) was calculated and the fatty acid profile of quadriceps muscle was assessed. The results showed that piglets fed with the diet supplemented with GP, had significantly increased antioxidants mechanisms in almost all the tissues as shown by increases in GSH, H₂O₂ decomposition activity and TAC compared with control group. Piglets fed with the experimental diet exhibited decreased oxidative stress-induced damage to lipids and proteins as shown by decreases in TBARS and CARB in GP group compared with control. In addition, the experimental diet increased significantly ADG (by 23.65%) (P<0.05) and enhanced the growth of facultative probiotic bacteria (by up to 1.2 log colony forming units (CFU)/g) (P<0.05) and lactic acid bacteria (by up to 2.0 log CFU/g) (P<0.05) in GP group compared with the control group. GP supplementation inhibited the growth of pathogen populations such as Enterobacteriacae (by up to 1.8 log CFU/g) (P<0.05) and Campylobacter jejuni (by up to 1.0 log CFU/g) (P<0.05). Regarding fatty acid composition of meat, GP inclusion in piglets’ diet increased significantly n-3 fatty acids (EPA; C20 : 5n-3, DHA; C22 : 6n-3, α-linolenic acid; C18 : 3n-3) and decreased significantly n-6/n-3 ratio compared with control (P<0.05). The results suggested that dietary GP supplementation may have a beneficial impact on piglets’ welfare and may improve productivity as well as meat quality.     

Effects of finishing diet sorting and digestibility on performance and feed efficiency in beef steers

The aim of this study was to test the hypotheses that differences in residual feed intake (RFI) of beef steers are related to diet sorting, diet nutrient composition, energy intake and apparent digestibility. To phenotype steers for RFI, 69 weaned Angus × Hereford steers were fed individually for 56 days. A finishing diet was fed twice daily on an ad libitum basis to maintain approximately 0.5 to 1.0 kg refusals. Diet offered and refused was measured daily, and DM intakes (DMI) were calculated by difference. Body weights were recorded at 14-day intervals following an 18-h solid feed withdrawal. The residual feed intake was determined as the residual of the regression of DMI versus mid-test metabolic BW (BW ^0.75) and average daily gain (ADG). Particle size distributions of diet and refusals were determined using the Penn State Particle Separator to quantify diet sorting. Sampling of diet, refusals and feces were repeated in four sampling periods which occurred during weeks 2, 4, 6 and 8 of the study. Particle size distributions of refusals and diet were analyzed in weeks 2, 4 and 6, and sampling for chemical analysis of refusals and feces occurred in all four periods. Indigestible neutral detergent fiber (288 h in situ) was used as an internal marker of apparent digestibility. We conclude that preference for the intakes of particles > 19 mm and 4 to 8 mm were negatively correlated to RFI and ADG, respectively. Although steers did sort to consume a different diet composition than offered, diet sorting did not impact intake energy, digestible energy or DM digestibility.     

Differential hepatic oxidative status in steers with divergent residual feed intake phenotype

Oxidative stress occurs when oxidant production exceeds the antioxidant capacity to detoxify the reactive intermediates or to repair the resulting damage. Feed efficiency has been associated with mitochondrial function due to its impact on cell energy metabolism. However, mitochondria are also recognized as a major source of oxidants. The aim of this study was to determine lipid and protein oxidative stress markers, and gene and protein expression as well as activity of antioxidant enzymes in the liver of steers of divergent residual feed intake (RFI) phenotypes. Hereford steers (n = 111) were evaluated in post-weaning 70 days standard test for RFI. Eighteen steers exhibiting the greatest (n = 9; high-RFI) and the lowest (n = 9; low-RFI) RFI values were selected for this study. After the test, steers were managed together under grazing conditions until slaughter when they reached the slaughter body weight. At slaughter, hepatic samples were obtained, were snap-frozen in liquid nitrogen and stored at −80°C until analyses. Hepatic thiobarbituric acid reactive species and protein carbonyls were greater (P = 0.05) and hepatic 4-hydroxynonenal protein adducts tended (P = 0.10) to be greater for high- than low-RFI steers. Hepatic gene expression glutathione peroxidase 4, glutamate–cysteine ligase catalytic subunit and peroxiredoxin 5 mRNA was greater (P ≤ 0.05) and glutathione peroxidase 3 mRNA tended (P = 0.10) to be greater in low- than high-RFI steers. Hepatic protein expression and enzyme activity of manganese superoxide dismutase and glutathione peroxidase enzyme activity tended (P ≤ 0.10) to be greater for low- than high-RFI steers. High-efficiency steers (low-RFI) probably had better hepatic oxidative status which was strongly associated with greater antioxidant ability near to the oxidant production site and, therefore, reduced oxidative stress of the liver. Decreased hepatic oxidative stress would reduce maintenance requirements due to a lower protein and lipid turnover and better efficiency in the use of energy.     

The effect of type of shade on physiology,behaviour and performance of grazing steers

Research has addressed the issue of type of shade mainly on feedlots and high-producing dairy farms, but more studies are needed on the impact of shade on grazing beef cattle in a low-to-medium plane of nutrition. A 63-day grazing study using 24 British steers (268±4 kg) was undertaken in Uruguay (33°14'S, 54°15'W) to determine the effect of type of artificial shade on tympanic temperature (TT), behaviour and performance during summer. Cattle were allocated to six paddocks with an area of 2.5 ha each (four steers/paddock) continuously grazed. Treatments (two paddocks/treatment) were unshaded (US) and shaded with either 35% (35S) or 80% (80S) blockage of solar radiation. TT was recorded during 12 days placing an automatic device near the tympanic membrane inside the animal’s ear. Animal behaviours were measured by live observations of animals every 15 min from 1100 to 1600 h six times during the experimental period. According to the temperature–humidity index (THI), cattle was in the ‘normal’ category (THI<70, absence of heat stress) during 50% of the time, the rest being exposed to some degree of heat stress including 15% of the time with environmental conditions. Black globe temperature and surface soil temperature decreased as solar protection increased under the shade structure. Steers spent more time under the 80S structure than under the 35S between 1100 and 1600 h (83% and 49% of the time, respectively). Average 24-h TT did not differ among treatments (mean±s.e. 38.79±0.04ºC). Minimum TT was registered at 0700 h for all treatments (37.92±0.08ºC), whereas maximum TT was reached at 1700 h for both control group (39.73±0.18ºC) and 35% shade (39.48±0.12ºC) and at 1900 h for 80% shade (39.57±0.15ºC). Neither the provision nor the type of shade affected animal performance (0.622±0.060 kg/a per day), indicating the ability of cattle to acclimate and/or compensate for eventually short-term severe heat stress events. The results of this experiment suggest that the provision of shade with either 35% or 80% of blockage of solar radiation is recommended for the improvement of cattle well-being (expressed through changes in behaviour) without significantly affecting animal performance and TT. However, the overall results of the 63 days of the study can mask or dilute punctual effects of short heat stress events on cattle. More powerful experimental designs are required to address this issue in temperate regions.     

Supplementing a yeast-derived product to enhance productive and health responses of beef steers

This experiment evaluated the impacts of supplementing a yeast-derived product (Celmanax; Church & Dwight Co., Inc., Princeton, NJ, USA) on productive and health responses of beef steers, and was divided into a preconditioning (days 4 to 30) and feedlot receiving phase (days 31 to 69). In all, 84 Angus × Hereford steers were weaned on day 0 (BW=245±2 kg; age=186±2 days), and maintained in a single group from days 0 to 3. On day 4, steers were allocated according to weaning BW and age to a 21-pen drylot (4 steers/pen). Pens were randomly assigned to (n=7 pens/treatment): (1) no Celmanax supplementation during the study, (2) Celmanax supplementation (14 g/steer daily; as-fed) from days 14 to 69 or (3) Celmanax supplementation (14 g/steer daily; as-fed) from days 31 to 69. Steers had free-choice access to grass-alfalfa hay, and were also offered a corn-based concentrate beginning on day 14. Celmanax was mixed daily with the concentrate. On day 30, steers were road-transported for 1500 km (24 h). On day 31, steers returned to their original pens for the 38-day feedlot receiving. Shrunk BW was recorded on days 4, 31 and 70. Feed intake was evaluated daily (days 14 to 69). Steers were observed daily (days 4 to 69) for bovine respiratory disease (BRD) signs. Blood samples were collected on days 14, 30, 31, 33, 35, 40, 45, 54 and 69, and analyzed for plasma cortisol, haptoglobin, IGF-I, and serum fatty acids. Preconditioning results were analyzed by comparing pens that received (CELM) or not (CONPC) Celmanax during the preconditioning phase. Feedlot receiving results were analyzed by comparing pens that received Celmanax from days 14 to 69 (CELPREC), days 31 to 69 (CELRECV) or no Celmanax supplementation (CON). During preconditioning, BRD incidence was less (P=0.03) in CELM v. CONPC. During feedlot receiving, average daily gain (ADG) (P=0.07) and feed efficiency (P=0.08) tended to be greater in CELPREC and CELRECV v. CON, whereas dry matter intake was similar (P⩾0.29) among treatments. No other treatment effects were detected (P⩾0.20). Collectively, Celmanax supplementation reduced BRD incidence during the 30-day preconditioning. Moreover, supplementing Celmanax tended to improve ADG and feed efficiency during the 38-day feedlot receiving, independently of whether supplementation began during preconditioning or after feedlot entry. These results suggest that Celmanax supplementation benefits preconditioning health and feedlot receiving performance in beef cattle.     

N-acetylcysteine modulates doxorubicin-induced oxidative stress and antioxidant vitamin concentrations in liver of rats

Doxorubicin (DOX) is a chemotherapeutic agent, and is widely used in cancer treatment. The most common side effect of DOX was indicated on cardiovascular system by experimental studies. There are some studies suggesting oxidative stress-induced toxic changes on liver related to DOX administration. The aim of the present study was to evaluate whether antioxidant N-acetylcysteine (NAC) relieves oxidative stress in DOX- induced liver injury in rat. Twenty-four male rats were equally divided into three groups. First group was used as a control. Second group received single dose of DOX. NAC for 10 days was given to constituting the third group after giving one dose of DOX. After 10 days of the experiment, liver tissues were taken from all animals. Lipid peroxidation (LP) levels were higher in the DOX group than in control whereas LP levels were lower in the DOX+NAC group than in control. Vitamin C and vitamin E levels were lower in the DOX group than in control whereas vitamin C and vitamin E levels were higher in the DOX+NAC group than in the DOX group. Reduced glutathione levels were higher in the DOX+NAC group than in control and DOX group. Glutathione peroxidase, vitamin A and β-carotene values were not changed in the three groups by DOX and NAC administrations. In histopathological evaluation of DOX group, there were mononuclear cell infiltrations, vacuolar degeneration, hepatocytes with basophilic nucleus and sinusoidal dilatations. The findings were totally recovered by NAC administration. In conclusion, N-acetylcysteine induced modulator effects on the doxorubicin-induced hepatoxicity by inhibiting free radical production and supporting the antioxidant vitamin levels.     

Selection of antioxidants against ovarian oxidative stress in mouse model

Oxidative stress (OS) plays an important role in the process of ovarian granulosa cell apoptosis and follicular atresia. The aim of this study was to select antioxidant against OS in ovary tissue. Firstly, we chose the six antioxidants and analyzed the reactive oxygen species (ROS) level in the ovary tissue. The results showed that proanthocyanidins, gallic acid, curcumin, and carotene decrease the ROS level compared with control group. We further demonstrated that both proanthocyanidins and gallic acid increase the antioxidant enzymes activity. Moreover, change in the ROS level was not observed in proanthocyanidins and gallic acid group of brain, liver, spleen, and kidney tissues. Finally, we found that proanthocyanidins and gallic acid inhibit pro‐apoptotic genes expression in granulosa cells. Taken together, proanthocyanidins and gallic acid may be the most acceptable and optimal antioxidants specifically against ovarian OS and also may be involved in the inhibition of granulosa cells apoptosis in mouse ovary.     

Impact of adding nitrate or increasing the lipid content of two contrasting diets on blood methaemoglobin and performance of two breeds of finishing beef steers

Adding nitrate to the diet or increasing the concentration of dietary lipid are effective strategies for reducing enteric methane emissions. This study investigated their effect on health and performance of finishing beef cattle. The experiment was a two×two×three factorial design comprising two breeds (CHX, crossbred Charolais; LU, Luing); two basal diets consisting of (g/kg dry matter (DM), forage to concentrate ratios) 520 : 480 (Mixed) or 84 : 916 (Concentrate); and three treatments: (i) control with rapeseed meal as the main protein source replaced with either (ii) calcium nitrate (18 g nitrate/kg diet DM) or (iii) rapeseed cake (RSC, increasing acid hydrolysed ether extract from 25 to 48 g/kg diet DM). Steers (n=84) were allocated to each of the six basal diet×treatments in equal numbers of each breed with feed offered ad libitum. Blood methaemoglobin (MetHb) concentrations (marker for nitrate poisoning) were monitored throughout the study in steers receiving nitrate. After dietary adaptation over 28 days, individual animal intake, performance and feed efficiency were recorded for a test period of 56 days. Blood MetHb concentrations were low and similar up to 14 g nitrate/kg diet DM but increased when nitrate increased to 18 g nitrate/kg diet DM (P<0.001). An interaction between basal diet and day (P<0.001) indicated that MetHb% was consistently greater in Concentrate – than Mixed-fed steers at 18 g nitrate/kg diet DM. Maximum individual MetHb% was 15.4% (of total Hb), which is lower than considered clinically significant (30%). MetHb concentrations for individual steers remained consistent across time. Concentrate-fed steers were more efficient (lower residual feed intake (RFI) values) than Mixed-fed steers (P<0.01), with lower dry matter intake (DMI) (kg/day) (P<0.001) and similar average daily gain (ADG). CHX steers were more efficient (lower RFI; P<0.01) than LU steers with greater ADG (P<0.01), lower DMI (/kg BW; P<0.01) and lower fat depth (P<0.001). ADG, BW or DMI did not differ across dietary treatments (P>0.05). Neither basal diet nor treatment affected carcass quality (P>0.05), but CHX steers achieved a greater killing out proportion (P<0.001) than LU steers. Thus, adding nitrate to the diet or increasing the level of dietary lipid through the use of cold-pressed RSC, did not adversely affect health or performance of finishing beef steers when used within the diets studied.     

Behavioral and monoamine changes following severe vitamin C deficiency

Severe vitamin C deficiency (ascorbic acid; AA) was induced in gulo?/? mice incapable of synthesizing their own AA. A number of behavioral measures were studied before and during the deprivation period, including a scorbutic period, during which weight loss was observed in the mice. Mice were then resuscitated with AA supplements. During the scorbutic period, gulo?/? mice showed decreased voluntary locomotor activity, diminished physical strength, and increased preference for a highly palatable sucrose reward. These behaviors all returned to control levels following resuscitation. Altered trial times in subordinate mice in the tube test for social dominance in the AA‐deprived mice persisted following resuscitation and may signify a depressive‐like behavior in these mice. Biochemical analyses were undertaken following a second deprivation period. AA deficiency was accompanied by decreased blood glucose levels, oxidative damage to lipids and proteins in the cortex, and decreases in dopamine and serotonin metabolites in both the cortex and striatum. Given the reasonably high proportions of the population that do not consume sufficient AA in the diet, these data have important implications for physical and psychological function in the general population.     

Assessing feed efficiency in beef steers through feeding behavior, infrared thermography and glucocorticoids

A better understanding of the factors regulating feed efficiency and their potential as predictors of feed efficiency in cattle is needed. Therefore, the potential of three classes of traits, namely, feeding behavior characteristics: daily time at feeder (TF; min/day), time per meal (TM; min), meal size (MS; g DM), eating rate (ER; g DM/min), number of daily meals (NM) and daily visits to the feeder (VF); infrared (IR) thermography traits (°C): eye (EY), cheek (CK), snout (SN), ribs (RB) and hind area (HA); and glucocorticoid levels: fecal cortisol metabolites (FCM; ng/g) and plasma cortisol (PC; ng/ml) as predictors of efficiency were evaluated in 91 steers (436 ± 37 kg) over 2 years (Y1 = 46; Y2 = 45). Additionally, the individual traits of each of these three classes were combined to define three single traits. Individual daily feed intake of a corn silage and high-moisture corn-based diet was measured using an automated feeding system. Body weight and thermographs were taken every 28 days over a period of 140 days. Four productive performance traits were calculated: daily dry matter intake (DMI), average daily gain (ADG), feed to gain ratio (F : G) and residual feed intake (RFI). Steers were also classified into three RFI categories (low-, medium- and high-RFI). Among the feeding behavior characteristics, MS and ER were correlated with all efficiency traits (range: 0.26 to 0.75). Low-RFI (more efficient steers) had smaller MS, lower ER and fewer VF in comparison to high-RFI steers. Less efficient steers (high-RFI) performed more VF during the nocturnal period than more efficient steers. More efficient steers had lower CK and SN temperatures than less efficient steers (28.1°C v. 29.2°C and 30.0°C v. 31.2°C), indicating greater energetic efficiency for low-RFI steers. In terms of glucocorticoids, PC was not correlated with efficiency traits. In contrast, more efficient steers had higher FCM in comparison to less efficient steers (51.1 v. 31.2 ng/g), indicating that a higher cortisol baseline is related to better feed efficiency. The overall evaluation of the three classes of traits revealed that feeding behavior, IR thermography and glucocorticoids accounted for 18%, 59% and 7% of the total variation associated with RFI, respectively. These classes of traits have usefulness in the indirect assessment of feed efficiency in cattle. Among them, IR thermography was the most promising alternative to screen cattle for this feed efficiency. These findings might have application in selection programs and in the better understanding of the biological basis associated with productive performance.     

Prevalence and antimicrobial susceptibility of Salmonella spp. isolates from US cattle in feedlots in 1999 and 2000

AIMS: Faecal samples from cattle in US feedlots were evaluated for the presence of Salmonella. When Salmonella isolates were recovered the antimicrobial resistance patterns were determined. METHODS AND RESULTS: Faecal samples were collected from pen floors in 73 feedlots in 12 states during the period from October 1999 to September 2000. Pens of cattle selected for sampling were those that had been in the feedlot for the shortest period of time, the longest period of time and a randomly selected pen from the remaining pens. Faecal samples were cultured for Salmonella spp. and all Salmonella isolates were categorized by serotype. The susceptibilities of all isolates were determined using a panel of 17 antimicrobials. Overall, 6.3% (654/10,417) of the samples cultured positive for Salmonella spp. and 22.2% (94/422) of pens and 50.7% (37/73) of feedlots had one or more positive samples. There was little difference in the proportion of positive samples from short-fed (6.1%, 212/3482), random (6.4%, 217/3400) and long-fed (6.4%, 224/3485) pens of cattle. One of two pens of cattle that could not be attributed to a pen type had a single positive sample (2.0%, 1/50). Samples collected during the period of April to June (6.8%, 209/3054) and July to September (11.4%, 286/2500) were more likely to be positive than those collected during October to December (4.0%, 73/1838) and January to March (2.8%, 86/3025). The most common serotypes of Salmonella were dissimilar from those that are typically seen in human illness and cattle illness. The majority of isolates (62.8%, 441/702) were sensitive to all of the antimicrobials tested. Resistance was most frequently observed to tetracycline (35.9%, 252/702) followed by streptomycin (11.1%, 78/702), ampicillin (10.4%, 73/702) and chloramphenicol (10.4%, 73/702). Multiple resistance (resistance to > or =2 antimicrobials) was observed for 11.7% (82/702) of the isolates. CONCLUSIONS: Salmonella was isolated at low frequency from faeces of feedlot cattle and the serotypes were not those commonly associated with human illness. In addition most of the Salmonella isolates were sensitive to all the antimicrobials tested. SIGNIFICANCE AND IMPACT OF THE STUDY: This study contributes to understanding the ecology of Salmonella in cattle feedlots and the prevalence of resistance among potential food-borne pathogens.     

Antioxidative activity of thiophane [bis(3-(3,5-di-tret-butyl-4-hydroxyphenyl)propyl)sulfide]

The antioxidant activity, mutagenicity, and genotoxicity of bis(3-(3,5-di-tret-butyl-4-hydroxyphenyl)propyl)sulfide (thiophane) were studied using bacterial tests. The results of both an Ames test and SOS chromotest, as well as those studying the survival of E. coli cells deficient in enzymes responsible for the repair of DNA oxidative damage, testify to the fact that thiophane is not mutagenic and genotoxic, and it protects Salmonella typhimurium cells better than the well-known antioxidant trolox.     

Cyclic oxidation and reduction of protein methionine residues is an important antioxidant mechanism

Almost all forms of reactive oxygen species (ROS) oxidize methionine residues of proteins to a mixture of the R- and S-isomers of methionine sulfoxide. Because organisms contain methionine sulfoxide reductases (Msr's) that can catalyze the thioredoxin-dependent reduction of the sulfoxides back to methionine, it was proposed that the cyclic oxidation/reduction of methionine residues might serve as antioxidants to scavenge ROS, and also to facilitate the regulation of critical enzyme activities. We summarize here results of studies showing that organisms possess two different forms of Msr – namely, MsrA that catalyzes reduction of the S-isomer and MsrB that catalyzes the reduction of the R-isomer. Deletion of the msrA gene in mice leads to increased sensitivity to oxidative stress and to a decrease (40%) in the maximum lifespan. This suggests that elimination of both Msr's would have more serious consequences.     

Mitochondrial‐targeted peptide rapidly improves mitochondrial energetics and skeletal muscle performance in aged mice

Mitochondrial dysfunction plays a key pathogenic role in aging skeletal muscle resulting in significant healthcare costs in the developed world. However, there is no pharmacologic treatment to rapidly reverse mitochondrial deficits in the elderly. Here, we demonstrate that a single treatment with the mitochondrial‐targeted peptide SS‐31 restores in vivo mitochondrial energetics to young levels in aged mice after only one hour. Young (5 month old) and old (27 month old) mice were injected intraperitoneally with either saline or 3 mg kg^?1 of SS‐31. Skeletal muscle mitochondrial energetics were measured in vivo one hour after injection using a unique combination of optical and ³¹P magnetic resonance spectroscopy. Age‐related declines in resting and maximal mitochondrial ATP production, coupling of oxidative phosphorylation (P/O), and cell energy state (PCr/ATP) were rapidly reversed after SS‐31 treatment, while SS‐31 had no observable effect on young muscle. These effects of SS‐31 on mitochondrial energetics in aged muscle were also associated with a more reduced glutathione redox status and lower mitochondrial H₂O₂ emission. Skeletal muscle of aged mice was more fatigue resistant in situ one hour after SS‐31 treatment, and eight days of SS‐31 treatment led to increased whole‐animal endurance capacity. These data demonstrate that SS‐31 represents a new strategy for reversing age‐related deficits in skeletal muscle with potential for translation into human use.     

Neuroprotective activities of bacopa,lycopene, astaxanthin, and vitamin B12 combination on oxidative stress-dependent neuronal death

Oxidative stress is considered the common effector of the cascade of degenerative events in many neurological conditions. Thus, in this paper we tested different nutraceuticals in H₂O₂ in vitro model to understand if could represent an adjuvant treatment for neurological diseases. In this study, nutraceuticals bacopa, lycopene, astaxanthin, and vitamin B12 were used alone or in combination in human neuronal differentiated SH-SY5Y cells upon hydrogen peroxide-induced injury and neuroprotective, neuronal death pathways were analyzed. The nutraceuticals analyzed were able to protect H₂O₂ cytotoxic effects, through increasing cell viability and proteins involved in neuroprotection pathways and restoring proteins involved in cell death pathways. On this basis, it is possible to propose the use of these compounds as dietary supplement for the prevention or as adjuvant to the only symptomatic treatments so far available for neurodegenerative diseases.