Potential markers and metabolic processes involved in the mechanism of radiation-induced heart injury.

Irradiation of normal tissues leads to acute increase in reactive oxygen/nitrogen species that serve as intra- and inter-cellular signaling to alter cell and tissue function. In the case of chest irradiation, it can affect the heart, blood vessels, and lungs, with consequent tissue remodelation and adverse side effects and symptoms. This complex process is orchestrated by a large number of interacting molecular signals, including cytokines, chemokines, and growth factors.

Supplementation with n-3 polyunsaturated fatty acids to lipopolysaccharide-induced rats improved inflammation and functional properties of renal Na,K-ATPase.

Measurements of enzyme kinetics of renal Na, K-ATPase were used for characterization of ATP- and Na⁺-binding sites in rats that were subjected to 10 days of moderate inflammation that was induced by a single dose of Escherichia coli lipopolysaccharides (LPSs) at a dose of 1 mg kg⁻¹ body weight. We hypothesized that LPSs might initiate a malfunction of renal Na, K-ATPase, which is a key enzyme involved in regulation of sodium homeostasis in the organism. We also investigated the potential effect that fish oil (FO) has in the prevention of Na, K-ATPase alterations by administering FO daily at a dose of 30 mg kg⁻¹.

Antioxidant SMe1EC2 may attenuate the disbalance of sodium homeostasis in the organism induced by higher intake of cholesterol.

The study was focused to the influence of higher intake of cholesterol on properties of the renal Na,K-ATPase, a key system in maintaining the homeostasis of sodium in the organism. Feeding for 4 weeks with cholesterol-enriched food for rats afflicted with hereditary hypertriglyceridemia by itself enhanced the activity of Na,K-ATPase, probably as a consequence of higher number of active enzyme molecules as suggested by 32 % increase of V (max) value. This may be hypothesized as a reason for the increased retention of sodium.

Effect of saliva from horse fly Hybomitra bimaculata on kinetic properties of Na,K-ATPase: possible role in regulation of relaxation.

The possible involvement of salivary gland extract (SGE) from horse flies in modifying hyperpolarization and relaxation via alterations in functional properties of sarcolemmal Na,K-ATPase in the host tissue was tested in vitro by application of various amounts of SGE from Hybomitra bimaculata.SGE in the amount of 3 µg proteins representing approximately the equivalent of one salivary gland of Hybomitra bimaculata induced a stimulatory effect on Na,K-ATPase at all ATP concentrations applied. This effect resulted from the improved ATP-binding site affinity in the Na,K-ATPase molecule, as implicated by the reduction in K(M).

Influence of sub-chronic diabetes mellitus on functional properties of renal Na(+),K(+)-ATPase in both genders of rats.

For characterization of Na(+),K(+)-ATPase, a key enzyme involved in maintenance of intracellular sodium homeostasis, expression of alpha1 subunit and the ATP- and Na(+)-binding properties were investigated by Western blot analysis and by enzyme kinetics, respectively. Previous studies documented time-dependent alteration of properties of renal Na(+),K(+)-ATPase from its mobilization after 8 days to serious deteriorations after 16 weeks of diabetes in rats. Characterizing the critical period during development of the disease, when mobilization of Na(+),K(+)-ATPase observed in the acute phase turns to its damage, we examined the enzyme properties after 8 weeks lasting diabetes which was induced by a single intraperitoneal administration of streptozotocin in a dose of 65 mg.

Dual effect of polyphenolic compounds on cardiac Na+/K+-ATPase during development and persistence of hypertension in rats.

The enzyme kinetics of cardiac Na(+)/K(+)-ATPase were used for characterizing the ATP- and Na(+)-binding sites after administration of red wine polyphenolic compounds (Provinol) during developing and sustained hypertension. Hypertension was induced in rats (LN group) by the nitric oxide synthase inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME, 40 mg*kg(-1)*day(-1)). Provinol (40 mg*kg(-1)*day(-1)) was applied during developing hypertension (LNPF4 group) and sustained hypertension (LNPF7/3 group).

Acute diabetes mellitus and its influence on renal Na,K-ATPase in both genders.

Due to the importance of renal Na,K-ATPase in maintaining the sodium homeostasis in the organism, its activity and abundance is intensively studied in condition of diabetes mellitus. The main subject of this study was the investigation of properties of renal Na,K-ATPase and abundance of its alpha1 subunit in view of possible gender-dependent differences in male and female diabetic rats. Diabetes was induced by a single intraperitoneal dose of streptozotocin in a dose of 65 mg.