Intestinal protein nitration induced by myeloperoxidase

Rationale. Heart failure (HF) is accompanied by the development of an imbalance between oxygen- and nitric oxide-derived free radical production leading to protein nitration. Both chlorinating and peroxidase cycle of Myeloperoxidase (MPO) contribute to oxidative and nitrosative stress and are involved in tyrosine nitration of protein. Ceruloplasmin (Cp) has antioxidant function through its ferroxidase I (FeOxI) activity and has recently been proposed as a physiological defense mechanism against MPO inappropriate actions.Objective. We investigated the relationship between plasma MPO-related chlorinating activity, Cp and FeOxI, and nitrosative stress, inflammatory, neurohormonal, and nutritional biomarkers in HF patients.Methods and Results. In chronic HF patients (n=81, 76±9 years, NYHA Class II (26); Class III (29); Class IV (26)) and age-matched controls (n=17, 75±11 years, CTR), plasma MPO chlorinating activity, Cp, FeOxI, nitrated protein, free Malondialdehyde, BNP, norepinephrine, hsCRP, albumin, and prealbumin were measured. Plasma MPO chlorinating activity, Cp, BNP, norepinephrine, and hsCRP were increased in HF versus CTR. FeOxI, albumin, and prealbumin were decreased in HF. MPO-related chlorinating activity was positively related to Cp (r= 0.363,P<0.001), nitrated protein, hsCRP, and BNP and inversely to albumin.Conclusions. Plasma MPO chlorinated activity is increased in elderly chronic HF patients and positively associated with Cp, inflammatory, neurohormonal, and nitrosative parameters suggesting a role in HF progression.

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PSVII-35 Late-Breaking Abstract: Microwave heat treatment feed effect on ruminal degradability and intestinal protein digestibility - a brief review

Journal of Animal Science ◽

10.1093/jas/skaa278.607 ◽

2020 ◽

Vol 98 (Supplement_4) ◽

pp. 342-343

Author(s):

Md Safiqur Rahaman Shishir ◽

Muhammad Jamal Khan ◽

Hassan Khanaki ◽

Graham Brodie ◽

Brendan Cullen ◽

...

Keyword(s):

Heat Treatment ◽

Protein Digestibility ◽

Soya Bean ◽

Canola Meal ◽

Canola Seed ◽

Intestinal Protein ◽

Bean Meal ◽

Ruminal Degradability ◽

Soya Bean Meal

Abstract Rumen degradability of crude protein (CP) of feed is a major factor that determines the utilization of CP in ruminant production. This study briefly reviewed the findings from six international studies of microwave (MW) heat treatment effect on feed CP rumen degradability and intestinal CP digestibility. Six in vitro studies of concentrate feed (canola seed, canola meal, soya bean meal, cottonseed meal, corn, and barley) showed a decrease in effective rumen degradability of dry matter and protein by 4–40% and 17–40%, respectively compared to control group (untreated concentrate feed). Among the six studies, four studies identified the MW heat treatment effect on intestinal protein digestibility. Due to MW heat treatment, canola seed, canola meal, soya bean meal, and cottonseed meal showed an increase in intestinal CP digestibility by 17%, 20%, 21%, and 19%, respectively. Overall the briefly reviewed studies showed that, MW heat treatment substantially reduced feed CP ruminal degradability and increased in vitro CP digestibility of ruminally undegraded CP.

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N-Acetyl Cysteine Overdose Inducing Hepatic Steatosis and Systemic Inflammation in Both Propacetamol-Induced Hepatotoxic and Normal Mice

Antioxidants ◽

10.3390/antiox10030442 ◽

2021 ◽

Vol 10 (3) ◽

pp. 442

Author(s):

Gunn-Guang Liou ◽

Cheng-Chi Hsieh ◽

Yi-Ju Lee ◽

Pin-Hung Li ◽

Ming-Shiun Tsai ◽

...

Keyword(s):

Inbred Mouse ◽

Serum Triglyceride ◽

Mouse Strains ◽

High Dose ◽

Therapeutic Effects ◽

Protein Nitration ◽

Cholesterol Levels ◽

Antioxidative Enzyme Activities ◽

Acetyl Cysteine ◽

Dose Dependent

Acetaminophen (APAP) overdose induces acute liver damage and even death. The standard therapeutic dose of N-acetyl cysteine (NAC) cannot be applied to every patient, especially those with high-dose APAP poisoning. There is insufficient evidence to prove that increasing NAC dose can treat patients who failed in standard treatment. This study explores the toxicity of NAC overdose in both APAP poisoning and normal mice. Two inbred mouse strains with different sensitivities to propacetamol-induced hepatotoxicity (PIH) were treated with different NAC doses. NAC therapy decreased PIH by reducing lipid oxidation, protein nitration and inflammation, and increasing glutathione (GSH) levels and antioxidative enzyme activities. However, the therapeutic effects of NAC on PIH were dose-dependent from 125 (N125) to 275 mg/kg (N275). Elevated doses of NAC (400 and 800 mg/kg, N400 and N800) caused additional deaths in both propacetamol-treated and normal mice. N800 treatments significantly decreased hepatic GSH levels and induced inflammatory cytokines and hepatic microvesicular steatosis in both propacetamol-treated and normal mice. Furthermore, both N275 and N400 treatments decreased serum triglyceride (TG) and induced hepatic TG, whereas N800 treatment significantly increased interleukin-6, hepatic TG, and total cholesterol levels. In conclusion, NAC overdose induces hepatic and systemic inflammations and interferes with fatty acid metabolism.

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S-Nitrosothiol Signaling Is involved in Regulating Hydrogen Peroxide Metabolism of Zinc-Stressed Arabidopsis

Plant and Cell Physiology ◽

10.1093/pcp/pcz138 ◽

2019 ◽

Vol 60 (11) ◽

pp. 2449-2463 ◽

Cited By ~ 5

Author(s):

Zs Kolbert ◽

ï¿½ Molnï¿½r ◽

D Olï¿½h ◽

G Feigl ◽

E Horvï¿½th ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Plant Cells ◽

Thioredoxin Reductase ◽

Protein S ◽

Protein Nitration ◽

Wild Type ◽

Accumulation Capacity ◽

Zn Tolerance ◽

Activity Loss ◽

New Evidence

Abstract Accumulation of heavy metals such as zinc (Zn) disturbs the metabolism of reactive oxygen (e.g. hydrogen peroxide, H2O2) and nitrogen species (e.g. nitric oxide, NO; S-nitrosoglutathione, GSNO) in plant cells; however, their signal interactions are not well understood. Therefore, this study examines the interplay between H2O2 metabolism and GSNO signaling in Arabidopsis. Comparing the Zn tolerance of the wild type (WT), GSNO reductase (GSNOR) overexpressor 35S::FLAG-GSNOR1 and GSNOR-deficient gsnor1-3, we observed relative Zn tolerance of gsnor1-3, which was not accompanied by altered Zn accumulation capacity. Moreover, in gsnor1-3 plants Zn did not induce NO/S-nitrosothiol (SNO) signaling, possibly due to the enhanced activity of NADPH-dependent thioredoxin reductase. In WT and 35S::FLAG-GSNOR1, GSNOR was inactivated by Zn, and Zn-induced H2O2 is directly involved in the GSNOR activity loss. In WT seedlings, Zn resulted in a slight intensification of protein nitration detected by Western blot and protein S-nitrosation observed by resin-assisted capture of SNO proteins (RSNO-RAC). LC-MS/MS analyses indicate that Zn induces the S-nitrosation of ascorbate peroxidase 1. Our data collectively show that Zn-induced H2O2 may influence its own level, which involves GSNOR inactivation-triggered SNO signaling. These data provide new evidence for the interplay between H2O2 and SNO signaling in Arabidopsis plants affected by metal stress.

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