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Current researchis focused on the influence of β-aminobutyric acid (BABA) on the metabolism of nitric oxide (NO), hydrogen sulfide (H2S), ascorbic acid, and abscisic acid (ABA) in strawberry fruit. The increases in ion leakage and malondialdehyde (MDA) concentration in strawberry fruit and the degradation of chlorophyll in the sepals of the fruit were markedly inhibited by BABA at 20 mM. BABA-immersed fruit exhibited lower activities and expressions of polygalacturonase (PG), pectinmethylesterase (PME), and ethylene biosynthetic enzymes compared to the control. Furthermore, BABA immersion evidently upgraded the metabolic levels of NO and H2S, including the enzymatic activities and intermediary contents of metabolites, which collectively enhanced the levels of endogenous NO and H2S contents in strawberry fruit. The high enzymatic activities and gene expressions of the AsA biosynthesis pathway jointly maintained AsA accumulation in the BABA-treated sample. The application of BABA led to a decrease in ABA concentration, which was associated with reduced activities and gene expression levels of key enzymes participating in ABA metabolism. Our experimental observations showed that immersion with BABA may be a highly promising means to delay senescence and reduce natural decay in strawberry fruit, and the alleviation in senescence using BABA may be attributed to the modulation of NO, H2S, AsA, and ABA metabolism. [ABSTRACT FROM AUTHOR]

Urine samples of female patients with overactive bladder (OAB) are characterized by low levels of nerve growth factor (NGF) and elevated concentrations of nitric oxide (NO) compared to healthy controls. We therefore examined how NO might regulate NGF synthesis using rat bladder smooth muscle (SMCs) and urothelial (UROs) cells in culture. In UROs, incubation in hyperglycemic conditions to mimic insulin insensitivity present in the OAB cohort increased secretion of NO and concomitantly decreased NGF, except when the NO synthase inhibitor, l -NAME (1 mM) was present. Sodium nitroprusside (SNP) (300 μM, 24 h), a NO generator, decreased NGF levels and decreased cyclic GMP (cGMP) content, a process validated by the cGMP synthase inhibitor ODQ (100 μM). Alternatively, SNP increased mRNA of both NGF and matrix metalloproteinase-9 (MMP-9). MMP-9 knockout of UROs by Crispr-Cas9 potently decreased the effect of SNP on NGF, implying a dependent role of NO on MMP-9. On the other hand, matrix metalloproteinase-7 (MMP-7) activity was increased by SNP, which taken together with increase in NGF mRNA, suggests a compensatory mechanism. In SMCs, hyperglycemic conditions had the same effect on extracellular content of NO and NGF than in UROs. SNP also decreased NGF secretion but increased cGMP content. Stable permeable analogs of cGMP 8-(4-Chlorophenylthio)-cGMP (1 mM) and N2,2′-O-Dibutyryl-cGMP (3 mM) inhibited NGF release. NGF and MMP-9 mRNA expression was unchanged by SNP. Deletion of MMP-9 in SMCs by Crispr-Cas9 did not alter the effect of SNP. Finally, SNP decreased MMP-7 activity, diminishing the conversion of proNGF to NGF. These results demonstrate that enhanced NO secretion triggered by high glucose decreases NGF secretion through pathways unique for each cell type that involve cGMP and proteases MMP-7 and MMP-9. These results might help to explain our observations from the urine from patients with OAB associated with metabolic syndrome. • Hyperglycemic medium increases the release of nitric oxide by bladder cells. • Nitric oxide decreases the release of mature nerve growth factor. • Changes in cyclic GMP is required to mediate nitric oxide action. • Matrix metalloproteinases 7 and 9 are involved in neurotrophin proteolysis. [ABSTRACT FROM AUTHOR]

Metabolic syndrome is considered to be a cluster of disorders that directly contribute to the development of cardiovascular disease and are characterized by chronic systemic infl ammation. Numerous epidemiological data indicate that an adverse intrauterine environment, caused by the peculiarities of the nutritional status or placental insuffi ciency in a woman with metabolic syndrome, can “program” the susceptibility of the fetus to further development of cardiovascular and metabolic diseases, has an impact on cognitive and behavioral development. Nitric oxide (NO) plays a critical role in the pathogenesis of components of the metabolic syndrome. Children born prematurely have a high incidence of brain damage, which can lead to motor, cognitive, behavioral, social and sensory disorders. The purpose the research was the study of the effect of the eNOS gene polymorphism and indicators of nitric oxide metabolism on the neonatal consequences in prematurely born children from mothers with metabolic syndrome. Material and methods. A study was conducted in which 100 premature infants were included. Two groups were formed: the main group (n=34), which included preterm infants (birth weight 2145.29±148.19 g and gestational age 33.18±0.55 weeks) of mothers with metabolic syndrome, and the comparison group (n=66), which included preterm infants (birth weight 2295.99±101.45 and gestational age 34.03±0.45 weeks) of mothers without metabolic syndrome. The children underwent a genetic study – determination of the polymorphism of the eNOS gene, as well as the level of nitrites, nitrates and nitrosothiols in the urine. By decision of the bioethics commission No. 217 dated 12.06.2023, the materials of the scientifi c work comply with the Rules of Humane Treatment of Patients. Traditional methods of parametric and nonparametric statistics were used; nonparametric methods were used to analyze qualitative characteristics expressed mainly in percentages. The methods of parametric statistics were used to check the normality of the distribution of quantitative characteristics using the Kolmogorov- Smirnov criterion. Statistical processing of the obtained results was carried out using the package of application programs EXCEL-2003® and STATA version 11 for Windows (StataCorp, Texas, USA). The work was carried out as part of the scientifi c and experimental work of the Department of Pediatrics #1 with Neonatology of the Poltava State Medical University “To develop clinical and laboratory criteria, methods of predicting and preventing metabolic disoders in young children (state registration number 0120U102856). Results. The most common diseases in the infants of the studied groups were the consequences of intrauterine hypoxia (44.1%) and respiratory failure requiring artifi cial lung ventilation (50.0%), although no signifi cant diff erences were found in the prevalence of these conditions. We identifi ed the presence of signifi cant associations between the consequences of intrauterine hypoxia and the levels of nitrates (OR 1.19; 95% CI 1.01-1.40; p=0.042), nitrosothiols (OR 1.19; 95% CI 0.99-1.42; p=0.050) and the polymorphic genotype 4aa/ab of the eNOS gene (OR 0.28; 95% CI 0.12-0.67; p=0.004). Analysis of systemic hemodynamics revealed no signifi cant diff erences in baseline values between preterm infants with and without intrauterine hypoxia, but we did observe an association with urine output on day 3 of life. To fi nally clarify the complex infl uence of indicators of nitrate metabolism on the development of intrauterine hypoxia and to predict the development of consequences of this condition in premature infants, the following indicators are included in the regression prognostic model: the level of nitrates, nitrites, 4aa/4ab genotype and urine output on the third day of life. As the research results show, there is a direct reliable relationship with nitrates and an inverse relationship with nitrites, 4aa/4ab genotype and urine output. This prediction model has high operating characteristics – the area under the ROC curve is 0.8168. Some mechanisms of the infl uence of maternal metabolic syndrome on the development of relevant disorders in newborns are known, including disorders of nitric oxide synthesis, endothelial dysfunction, and oxidative stress. In our study, the consequences of intrauterine hypoxia were reliably associated with an increase in the concentration of urinary nitrates and a decrease in nitrites, as well as the absence of the 4aa/ab genotype, which is associated with reduced release of nitric oxide. There is evidence that nitric oxide can have both protective and deleterious eff ects, depending on factors such as nitric oxide synthase isoform and duration of exposure to hypoxia. Conclusions. In preterm infants born to mothers with metabolic syndrome, elevated urinary nitrate levels and the absence of the eNOS 4aa/ab genotype increase the likelihood of suff ering the consequences of intrauterine hypoxia.

Metabolic syndrome is considered to be a cluster of disorders that directly contribute to the development of cardiovascular disease and are characterized by chronic systemic inflammation. Numerous epidemiological data indicate that an adverse intrauterine environment, caused by the peculiarities of the nutritional status or placental insufficiency in a woman with metabolic syndrome, can "program" the susceptibility of the fetus to further development of cardiovascular and metabolic diseases, has an impact on cognitive and behavioral development. Nitric oxide (NO) plays a critical role in the pathogenesis of components of the metabolic syndrome. Children born prematurely have a high incidence of brain damage, which can lead to motor, cognitive, behavioral, social and sensory disorders. The purpose the research was the study of the effect of the eNOS gene polymorphism and indicators of nitric oxide metabolism on the neonatal consequences in prematurely born children from mothers with metabolic syndrome. Material and methods. A study was conducted in which 100 premature infants were included. Two groups were formed: the main group (n=34), which included preterm infants (birth weight 2145.29±148.19 g and gestational age 33.18±0.55 weeks) of mothers with metabolic syndrome, and the comparison group (n=66), which included preterm infants (birth weight 2295.99±101.45 and gestational age 34.03±0.45 weeks) of mothers without metabolic syndrome. The children underwent a genetic study - determination of the polymorphism of the eNOS gene, as well as the level of nitrites, nitrates and nitrosothiols in the urine. By decision of the bioethics commission No. 217 dated 12.06.2023, the materials of the scientific work comply with the Rules of Humane Treatment of Patients. Traditional methods of parametric and nonparametric statistics were used; nonparametric methods were used to analyze qualitative characteristics expressed mainly in percentages. The methods of parametric statistics were used to check the normality of the distribution of quantitative characteristics using the Kolmogorov-Smirnov criterion. Statistical processing of the obtained results was carried out using the package of application programs EXCEL-2003® and STATA version 11 for Windows (StataCorp, Texas, USA). The work was carried out as part of the scientific and experimental work of the Department of Pediatrics #1 with Neonatology of the Poltava State Medical University "To develop clinical and laboratory criteria, methods of predicting and preventing metabolic disoders in young children (state registration number 0120U102856). Results. The most common diseases in the infants of the studied groups were the consequences of intrauterine hypoxia (44.1%) and respiratory failure requiring artificial lung ventilation (50.0%), although no significant differences were found in the prevalence of these conditions. We identified the presence of significant associations between the consequences of intrauterine hypoxia and the levels of nitrates (OR 1.19; 95% CI 1.01-1.40; p=0.042), nitrosothiols (OR 1.19; 95% CI 0.99-1.42; p=0.050) and the polymorphic genotype 4aa/ab of the eNOS gene (OR 0.28; 95% CI 0.12-0.67; p=0.004). Analysis of systemic hemodynamics revealed no significant differences in baseline values between preterm infants with and without intrauterine hypoxia, but we did observe an association with urine output on day 3 of life. To finally clarify the complex influence of indicators of nitrate metabolism on the development of intrauterine hypoxia and to predict the development of consequences of this condition in premature infants, the following indicators are included in the regression prognostic model: the level of nitrates, nitrites, 4aa/4ab genotype and urine output on the third day of life. As the research results show, there is a direct reliable relationship with nitrates and an inverse relationship with nitrites, 4aa/4ab genotype and urine output. This prediction model has high operating characteristics - the area under the ROC curve is 0.8168. Some mechanisms of the influence of maternal metabolic syndrome on the development of relevant disorders in newborns are known, including disorders of nitric oxide synthesis, endothelial dysfunction, and oxidative stress. In our study, the consequences of intrauterine hypoxia were reliably associated with an increase in the concentration of urinary nitrates and a decrease in nitrites, as well as the absence of the 4aa/ab genotype, which is associated with reduced release of nitric oxide. There is evidence that nitric oxide can have both protective and deleterious effects, depending on factors such as nitric oxide synthase isoform and duration of exposure to hypoxia. Conclusions. In preterm infants born to mothers with metabolic syndrome, elevated urinary nitrate levels and the absence of the eNOS 4aa/ab genotype increase the likelihood of suffering the consequences of intrauterine hypoxia. [ABSTRACT FROM AUTHOR]

Current researchis focused on the influence of β-aminobutyric acid (BABA) on the metabolism of nitric oxide (NO), hydrogen sulfide (H2S), ascorbic acid, and abscisic acid (ABA) in strawberry fruit. The increases in ion leakage and malondialdehyde (MDA) concentration in strawberry fruit and the degradation of chlorophyll in the sepals of the fruit were markedly inhibited by BABA at 20 mM. BABA-immersed fruit exhibited lower activities and expressions of polygalacturonase (PG), pectinmethylesterase (PME), and ethylene biosynthetic enzymes compared to the control. Furthermore, BABA immersion evidently upgraded the metabolic levels of NO and H2S, including the enzymatic activities and intermediary contents of metabolites, which collectively enhanced the levels of endogenous NO and H2S contents in strawberry fruit. The high enzymatic activities and gene expressions of the AsA biosynthesis pathway jointly maintained AsA accumulation in the BABA-treated sample. The application of BABA led to a decrease in ABA concentration, which was associated with reduced activities and gene expression levels of key enzymes participating in ABA metabolism. Our experimental observations showed that immersion with BABA may be a highly promising means to delay senescence and reduce natural decay in strawberry fruit, and the alleviation in senescence using BABA may be attributed to the modulation of NO, H2S, AsA, and ABA metabolism.

Cytoglobin (Cygb) has been identified as the major nitric oxide (NO) metabolizing protein in vascular smooth muscle cells (VSMCs) and is crucial for the regulation of vascular tone. In the presence of its requisite cytochrome B5a (B5)/B5 reductase-isoform-3 (B5R) reducing system, Cygb controls NO metabolism through the oxygen-dependent process of NO dioxygenation. Tobacco cigarette smoking (TCS) induces vascular dysfunction; however, the role of Cygb in the pathophysiology of TCS-induced cardiovascular disease has not been previously investigated. While TCS impairs NO biosynthesis, its effect on NO metabolism remains unclear. Therefore, we performed studies in aortic VSMCs with tobacco smoke extract (TSE) exposure to investigate the effects of cigarette smoke constituents on the rates of NO decay, with focus on the alterations that occur in the process of Cygb-mediated NO metabolism. TSE greatly enhanced the rates of NO metabolism by VSMCs. An initial increase in superoxide-mediated NO degradation was seen at 4 h of exposure. This was followed by much larger progressive increases at 24 and 48 h, accompanied by parallel increases in the expression of Cygb and B5/B5R. siRNA-mediated Cygb knockdown greatly decreased these TSE-induced elevations in NO decay rates. Therefore, upregulation of the levels of Cygb and its reducing system accounted for the large increase in NO metabolism rate seen after 24 h of TSE exposure. Thus, increased Cygb-mediated NO degradation would contribute to TCS-induced vascular dysfunction and partial inhibition of Cygb expression or its NO dioxygenase function could be a promising therapeutic target to prevent secondary cardiovascular disease. • Cytoglobin controls nitric oxide (NO) metabolism through NO dioxygenation. • Tobacco smoking exposure induces loss of vascular NO; however, the cause was unknown. • Vascular smooth muscle cell exposure first triggered increased superoxide generation. • This was followed by induction of cytoglobin and the B5/B5R reducing system. • Together, this greatly increased the rate of NO decay in vascular smooth muscle cells. [ABSTRACT FROM AUTHOR]

Background: Kidney cancer is a common adult malignancy in the USA. Clear cell renal cell carcinoma (ccRCC), the predominant subtype of kidney cancer, is characterized by widespread metabolic changes. Urea metabolism is one such altered pathway in ccRCC. The aim of this study was to elucidate the contributions of urea cycle enzymes, argininosuccinate synthase 1 (ASS1), and argininosuccinate lyase (ASL) towards ccRCC progression. Methods: We employed a combination of computational, genetic, and metabolomic tools along with in vivo animal models to establish a tumor-suppressive role for ASS1 and ASL in ccRCC. Results: We show that the mRNA and protein expression of urea cycle enzymes ASS1 and ASL are reduced in ccRCC tumors when compared to the normal kidney. Furthermore, the loss of ASL in HK-2 cells (immortalized renal epithelial cells) promotes growth in 2D and 3D growth assays, while combined re-expression of ASS1 and ASL in ccRCC cell lines suppresses growth in 2D, 3D, and in vivo xenograft models. We establish that this suppression is dependent on their enzymatic activity. Finally, we demonstrate that conservation of cellular aspartate, regulation of nitric oxide synthesis, and pyrimidine production play pivotal roles in ASS1+ASL-mediated growth suppression in ccRCC. Conclusions: ccRCC tumors downregulate the components of the urea cycle including the enzymes argininosuccinate synthase 1 (ASS1) and argininosuccinate lyase (ASL). These cytosolic enzymes lie at a critical metabolic hub in the cell and are involved in aspartate catabolism and arginine and nitric oxide biosynthesis. Loss of ASS1 and ASL helps cells redirect aspartate towards pyrimidine synthesis and support enhanced proliferation. Additionally, reduced levels of ASS1 and ASL might help regulate nitric oxide (NO) generation and mitigate its cytotoxic effects. Overall, our work adds to the understanding of urea cycle enzymes in a context-independent of ureagenesis, their role in ccRCC progression, and uncovers novel potential metabolic vulnerabilities in ccRCC. [ABSTRACT FROM AUTHOR]