A Putative D-Arabinono-1,4-lactone Oxidase, MoAlo1, Is Required for Fungal Growth, Conidiogenesis, and Pathogenicity in Magnaporthe oryzae

Magnaporthe oryzae is the causal agent of rice blast outbreaks. L-ascorbic acid (ASC) is a famous antioxidant found in nature. However, while ASC is rare or absent in fungi, a five-carbon analog, D-erythroascorbic acid (EASC), seems to appear to be a substitute for ASC. Although the antioxidant function of ASC has been widely described, the specific properties and physiological functions of EASC remain poorly understood. In this study, we identified a D-arabinono-1,4-lactone oxidase (ALO) domain-containing protein, MoAlo1, and found that MoAlo1 was localized to mitochondria. Disruption of MoALO1 (ΔMoalo1) exhibited defects in vegetative growth as well as conidiogenesis. The ΔMoalo1 mutant was found to be more sensitive to exogenous H2O2. Additionally, the pathogenicity of conidia in the ΔMoalo1 null mutant was reduced deeply in rice, and defective penetration of appressorium-like structures (ALS) formed by the hyphal tips was also observed in the ΔMoalo1 null mutant. When exogenous EASC was added to the conidial suspension, the defective pathogenicity of the ΔMoalo1 mutant was restored. Collectively, MoAlo1 is essential for growth, conidiogenesis, and pathogenicity in M. oryzae.

Biological Function of Plant Tannin and Its Application in Animal Health

Plant tannins are widely found in plants and can be divided into hydrolyzed tannins and condensed tannins. In recent years, researchers have become more and more interested in using tannin-rich plants and plant extracts in ruminant diets to improve the quality of animal products. Some research results show that plant tannins can effectively improve the quality of meat and milk, and enhance the oxidative stability of the product. In this paper, the classification and extraction sources of plant tannins are reviewed, as well as the biological functions of plant tannins in animals. The antioxidant function of plant tannins is discussed, and the influence of their structure on antioxidation is analyzed. The effects of plant tannins against pathogenic bacteria and the mechanism of action are discussed, and the relationship between antibacterial action and antioxidant action is analyzed. The inhibitory effect of plant tannins on many kinds of pathogenic viruses and their action pathways are discussed, as are the antiparasitic properties of plant tannins. The anti-inflammatory action of tannins and its mechanism are analyzed. The function of plant tannins in antidiarrheal action and its influencing factors are discussed. In addition, the effects of plant tannins as feed additives on animals and the influencing factors are reviewed in this paper to provide a reference for further research.

Effects of Plotytarya strohilacea Sieb. et Zuce Tannin on the Growth Performance, Oxidation Resistance, Intestinal Morphology and Cecal Microbial Composition of Broilers

The purpose of this experiment was to study the effects of Plotytarya strohilacea Sieb. et Zuce tannin on broilers growth performance, antioxidant function, intestinal development, intestinal morphology and the cecal microbial composition. In this experiment, a total of 360 1-day-old Arbor Acres male broilers were randomly divided into 4 treatment groups, with 6 replicates in each group and 15 broilers in each replicate. The control group (Control) was fed the basal diet, and the broilers were fed a basal diet supplemented with 0 (Control), 100 (PT1), 400 (PT2), and 800 (PT3) mg/kg Plotytarya strohilacea Sieb. et Zuce tannins for 42 days, respectively. The results showed that the average daily feed intake (ADFI) of the PT1 group was significantly lower than that of the control group, and there was a significant quadratic relationship between the ADFI and the concentration of tannin (P < 0.05). Compared with the control group, the F/G of broilers during the 22–42 days phase in the PT1 group showed a decreasing trend (P = 0.063). The serum catalase (CAT) activity in the PT1 group was significantly higher than those of the other three groups, and the effect was significantly quadratically related to the dosage (P < 0.05). The glutathione peroxidase (GSH-Px) activity in the PT1, PT2 and control groups were significantly higher than that of the PT3 group, and the effect was significantly quadratically related to the addition amount (P < 0.05). The serum total antioxidant capacity (T-AOC) activity in the PT1 group was significantly higher than that in the control group, and the effect was significantly quadratically related to the addition amount (P < 0.05). Compared to the control group, the villus height of jejunum in the PT1, PT2 and PT3 groups were significantly higher, and there was a significant quadratic relationship between the villus height of jejunum and the addition amount (P < 0.05). In addition, adding tannins to diets significantly increased Parabacteroides in the dominant genus (P < 0.05). In conclusion, dietary supplementation with Plotytarya strohilacea Sieb. et Zuce tannin improved the growth performance, antioxidant function, and intestinal morphology along with an increased abundance of Parabacteroides in the cecum, and the recommended dosage of tannin in broiler diets was 100 mg/kg.

Sod1 integrates oxygen availability to redox regulate NADPH production and the thiol redoxome

Cu/Zn superoxide dismutase (Sod1) is a highly conserved and abundant antioxidant enzyme that detoxifies superoxide (O2•−) by catalyzing its conversion to dioxygen (O2) and hydrogen peroxide (H2O2). Using Saccharomyces cerevisiae and mammalian cells, we discovered that a major aspect of the antioxidant function of Sod1 is to integrate O2 availability to promote NADPH production. The mechanism involves Sod1-derived H2O2 oxidatively inactivating the glycolytic enzyme, GAPDH, which in turn reroutes carbohydrate flux to the oxidative phase of the pentose phosphate pathway (oxPPP) to generate NADPH. The aerobic oxidation of GAPDH is dependent on and rate-limited by Sod1. Thus, Sod1 senses O2 via O2•− to balance glycolytic and oxPPP flux, through control of GAPDH activity, for adaptation to life in air. Importantly, this mechanism for Sod1 antioxidant activity requires the bulk of cellular Sod1, unlike for its role in protection against O2•− toxicity, which only requires <1% of total Sod1. Using mass spectrometry, we identified proteome-wide targets of Sod1-dependent redox signaling, including numerous metabolic enzymes. Altogether, Sod1-derived H2O2 is important for antioxidant defense and a master regulator of metabolism and the thiol redoxome.

Astaxanthin as a Novel Mitochondrial Regulator: A New Aspect of Carotenoids, beyond Antioxidants

Astaxanthin is a member of the carotenoid family that is found abundantly in marine organisms, and has been gaining attention in recent years due to its varied biological/physiological activities. It has been reported that astaxanthin functions both as a pigment, and as an antioxidant with superior free radical quenching capacity. We recently reported that astaxanthin modulated mitochondrial functions by a novel mechanism independent of its antioxidant function. In this paper, we review astaxanthin’s well-known antioxidant activity, and expand on astaxanthin’s lesser-known molecular targets, and its role in mitochondrial energy metabolism.

cDNA Cloning and Partial Characterization of the DJ-1 Gene from Tribolium castaneum

The DJ-1 gene is highly conserved across a wide variety of organisms and it plays a role in anti-oxidative stress mechanisms in cells. The red flour beetle, Tribolium castaneum, is widely used as a model insect species because it is easy to evaluate gene function in this species using RNA interference (RNAi). The T. castaneum DJ-1 (TcDJ-1) sequence is annotated in the T. castaneum genome database; however, the function and characteristics of the TcDJ-1 gene have not been elucidated. Here, we investigated the cDNA sequence of TcDJ-1 and partially characterized its function. First, we examined the TcDJ-1 amino acid sequence and found that it was highly conserved with sequences from other species. TcDJ-1 mRNA expression was higher in the early pupal and adult developmental stages. We evaluated oxidant tolerance in TcDJ-1 knockdown adults using paraquat and found that adults with TcDJ-1 knockdown exhibited increased sensitivity to paraquat. Our findings show that TcDJ-1 has an antioxidant function, as observed for DJ-1 from other insects. Therefore, these results suggest that TcDJ-1 protects against oxidative stress during metamorphosis.

INVESTIGATION OF THE SELENIUM STATUS AND ACTIVITY OF THE ANTIOXIDANT SYSTEM IN THE ROMANOV SHEEP IN THE NORTH-WESTERN REGION

The extension of the characteristics of the cattle ration is widely spread nowadays. One of the most significant nutritional element is selenium. Selenium has antioxidant function because it is a necessary part of the antioxidant enzyme glutathione peroxidase. There is a deficiency of selenium on the large territories of Russian Federation, especially on North-Western region. The selenium deficiency is the reason of different metabolic diseases and stiff lamb disease. All of the aforesaid leads to production loss. In this article it is firstly reported about selenium status, biochemistry characteristics and their variations after treatment selenium –containing drug among Romanov sheep in north-western region. In the course of study was found that selenium concertation in sheep serum was lower than normal. The selenium drug administration was led to an increase of serum selenium concertation

Effect of 2-Cys Peroxiredoxins Inhibition on Redox Modifications of Bull Sperm Proteins

Sperm peroxiredoxins (PRDXs) are moonlighting proteins which, in addition to their antioxidant activity, also act as redox signal transducers through PRDX-induced oxidative post-translational modifications of proteins (oxPTMs). Despite extensive knowledge on the antioxidant activity of PRDXs, the mechanisms related to PRDX-mediated oxPTMs are poorly understood. The present study aimed to investigate the effect of bull sperm 2-Cys PRDX inhibition by Conoidin A on changes in oxPTM levels under control and oxidative stress conditions. The results showed that a group of sperm mitochondrial (LDHAL6B, CS, ACO2, SDHA, ACAPM) and actin cytoskeleton proteins (CAPZB, ALDOA, CCIN) is oxidized due to the action of 2-Cys PRDXs under control conditions. In turn, under oxidative stress conditions, 2-Cys PRDX activity seems to be focused on antioxidant function protecting glycolytic, TCA pathway, and respiratory chain enzymes; chaperones; and sperm axonemal tubulins from oxidative damage. Interestingly, the inhibition of PRDX resulted in oxidation of a group of rate-limiting glycolytic proteins, which is known to trigger the switching of glucose metabolism from glycolysis to pentose phosphate pathway (PPP). The obtained results are expected to broaden the knowledge of the potential role of bull sperm 2-Cys in both redox signal transmission and antioxidant activity.