The mechanisms of the formation of cardiogenic afferent effects after the development of local immune damage to the heart]

Sensitivity of cardiac receptors to several substances after local immune heart damage and the nature of cardiogenic influences on the circulation were studied in acute experiments o anesthetized dogs. The depressor reflexes from the heart were shown to disappear during 30 min. after immune heart damage, and vagal afferent impulse activity decreased. After immune heart damage, cardiac sympathetic afferent fibres were more sensitive to endogenous biological substances than to vagal ones. The sympathetic cardiac afferent system is found to be more sensitive to chemical agents, which is a decisive factor in formation of cardiogenic influences on the circulation during pathological processes in the heart.     

Flagellin and outer surface proteins from Borrelia burgdorferi are not glycosylated

We investigated the presence of glycoproteins in Borrelia burgdorferi. We did not find any evidence for glycosylation of the major outer membrane proteins OspA and OspB or the structural flagellar proteins FlaB and FlaA. We suggest that glycoproteins present on the surface of B. burgdorferi may be tightly bound culture medium glycoproteins.     

The INA complex facilitates assembly of the peripheral stalk of the mitochondrial F1Fo‐ATP synthase

Mitochondrial F₁F_o‐ATP synthase generates the bulk of cellular ATP. This molecular machine assembles from nuclear‐ and mitochondria‐encoded subunits. Whereas chaperones for formation of the matrix‐exposed hexameric F₁‐ATPase core domain have been identified, insight into how the nuclear‐encoded F₁‐domain assembles with the membrane‐embedded F_o‐region is lacking. Here we identified the INA complex (INAC) in the inner membrane of mitochondria as an assembly factor involved in this process. Ina22 and Ina17 are INAC constituents that physically associate with the F₁‐module and peripheral stalk, but not with the assembled F₁F_o‐ATP synthase. Our analyses show that loss of Ina22 and Ina17 specifically impairs formation of the peripheral stalk that connects the catalytic F₁‐module to the membrane embedded F_o‐domain. We conclude that INAC represents a matrix‐exposed inner membrane protein complex that facilitates peripheral stalk assembly and thus promotes a key step in the biogenesis of mitochondrial F₁F_o‐ATP synthase.     

Tyrosine nitration as a key event of signal transduction that regulates functional state of the cell

This review is dedicated to the role of nitration of proteins by tyrosine residues in physiological and pathological conditions. First of all, we analyze the biochemical evidence of peroxynitrite formation and reactions that lead to its formation, types of posttranslational modifications (PTMs) induced by reactive nitrogen species, as well as three biological pathways of tyrosine nitration. Then, we describe two possible mechanisms of protein nitration that are involved in intracellular signal transduction, as well as its interconnection with phosphorylation/dephosphorylation of tyrosine. Next part of the review is dedicated to the role of proteins nitration in different pathological conditions. In this section, special attention is devoted to the role of nitration in changes of functional properties of actin—protein that undergoes PTMs both in normal and pathological conditions. Overall, this review is devoted to the main features of protein nitration by tyrosine residue and the role of this process in intracellular signal transduction in basal and pathological conditions.     

Sex-related differences in plasma amino acids of patients with ST-elevation myocardial infarction and glycine as risk marker of acute heart failure with preserved ejection fraction

Nowadays, the problem of preventing acute heart failure (AHF) in patients with ST-elevation myocardial infarction (STEMI) and preserved left-ventricular ejection fraction (pLVEF) is still not completely resolved, especially in late-presented patients. The purpose of study was: (1) assessment of free plasma amino acid (PAA) alterations in STEMI patients [not receiving reperfusion therapy (RT)], depending on sex and LVEF; (2) analysis of development of late/persistent AHF more than 48 h after admission (pAHF) in STEMI patients with pLVEF depending on PAA levels. This prospective cohort study included 92 STEMI patients (33 women and 59 men), not receiving RT. The free PAA were investigated by ion-exchange liquid-column chromatography. The women had significantly higher PAA levels than men in general cohort and cohort with pLVEF (n?=?69). There were associations between female sex and pAHF in general cohort (OR 3.7, p?=?0.004) and cohort with pLVEF (OR 11.4, p?=?0.0001) by logistic regression. The association between pAHF and glycine level [OR 2.5, p?<?0.0001; AUC 0.84, p?<?0.0001; 86.7% sensitivity and 77.8% specificity for?>?2.6 mg/dL] was revealed in cohort with pLVEF (including female and male). Glycine remained a predictor of pAHF with pLVEF by multivariable logistic regression adjusting for comorbidities, demographic and clinical variables. Higher rate of pAHF in female than in male STEMI patients with pLVEF is associated with higher plasma glycine in women. The glycine level may be genetically determinated by female sex. The plasma glycine?>?2.6 mg/dL is a predictor of pAHF in STEMI with pLVEF (including female and male).