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Biochemical and Pharmacological Rationales in Radiotracer Design
Published in Lelio G. Colombetti, Principles of Radiopharmacology, 2019
Raymond E. Counsell, Nancy Korn
While the precise function of these substances is unknown, the polyamines seem to play an important role in cell growth and development as evidenced by increased levels of polyamines (and especially putrescine and spermidine) in rapidly growing normal and neoplastic tissues, which are paralleled with reported corresponding increases in RNA and protein synthesis, and sometimes increases in DNA synthesis. Several excellent reviews have reported on the known biochemistry and pharmacology of the polyamines.*204-211 It has been proposed by Tabor and Tabor210 that the biochemical function of polyamines is probably related to the interaction of these polycationic substances with polyanionic macromolecules such as RNA and DNA.
Biogenic Amines in Plant Food
Published in Akula Ramakrishna, Victoria V. Roshchina, Neurotransmitters in Plants, 2018
Kamil Ekici, Abdullah Khalid Omer
Polyamines are essential compounds for growth and development in plants. Since only polyamines spermidine and spermine share a common precursor S-adenosylmethionine (SAM) with ethylene, they demonstrated competitive effects on functions in fruit development and ripening in many plants. Polyamines are essential compounds for growth and development in plants. Since polyamines only spermidine and spermine share a common precursor S-adenosylmethionine (SAM) with ethylene, they demonstrated competitive effects on functions in fruit development and ripening in many plants. In higher plants generally, the polyamines are found in both free and conjugated forms its endogenous levels depend on the external conditions of light and temperature. Especially in reproductive organs and seeds they appear as conjugated forms. There is no clear role envisaged for these conjugated polyamines in plants, but scanty reports suggest their possible involvement in plant defence (Sridevi et al., 2009). Increased polyamine levels were observed during somatic embryogenesis of carrot cell cultures (Fienberg et al., 1984) and in developing tomato fruits (Heimer et al., 1979). L-Tyrosine decarboxylase (TYDC) belongs to the aromatic L-amino acid decarboxylase enzyme family and catalyses the conversion of tyrosine to tyramine in plants (Park et al., 2012).
Molecular Mechanisms of Training Effects
Published in Atko Viru, Adaptation in Sports Training, 2017
The elevated output of spermine and spermidine during muscular exercises was mentioned above. These polyamines are known to stimulate proliferation and protein synthesis (see p. 205). Somatotropin stimulates the metabolic processes leading to the formation of spermidine and spermine.90
Drugs and nanoformulations for the management of Leishmania infection: a patent and literature review (2015-2022)
Published in Expert Opinion on Therapeutic Patents, 2023
Mariana Verdan, Igor Taveira, Flávia Lima, Fernanda Abreu, Dirlei Nico
Polyamines play a fundamental role in cell growth and differentiation. Arginine is an amino acid necessary for Leishmania and host metabolism [76]. Arginase is an enzyme responsible for the cleavage of arginine, producing ornithine and urea. In Leishmania, arginase is one of the relevant enzymes in the polyamine biosynthesis pathway, which is responsible for converting arginine into ornithine [77]. In the Leishmania glycosome, arginase is also involved in trypanothione biosynthesis. Da Silva and colleagues demonstrated fundamental arginase activity in L. amazonensis, confirming arginase as an essential molecular target [78]. This study showed that Leishmania mutants for arginase decreased the power of infection in vitro. By the way, any other critical metabolic marks are under investigation. We will not extend our discussion on this issue so as not to deviate from the topic.
Gastro-protective effect of Artemisia Sieberi essential oil against ethanol-induced ulcer in rats as revealed via biochemical, histopathological and metabolomics analysis
Published in Biomarkers, 2022
Naglaa M. Ammar, Heba A. Hassan, Rania F. Ahmed, Abd El-Nasser G. El-Gendy, Ahmed M. Abd-ElGawad, Abdel Razik H. Farrag, Mohamed A. Farag, Abdelsamed I. Elshamy, Sherif M. Afifi
In line with our results, (Casero and Pegg 2009) reported that polyamines play a critical role in many physiological and pathological processes presenting potential drug targets (Casero and Pegg 2009). Among these, cadaverine a metabolite of the microbiome biosynthesized by bacterial decarboxylation of lysine during protein hydrolysis showed a down-regulation in the ulcer group (Figure 3S, Figure 5) suggesting that gut microbiota metabolic machinery was also affected (Qi et al.2011). In a previous study, decreased levels of polyamines in serum samples were also observed (Takeuchi et al.2014). Pyrimidine metabolism presented another pathway affected in this inflammation model (Figure 5), with uracil, a pyrimidine being the most prominent altered metabolites (Figure 3S, Figure 5). The increased level of uracil in ulcer group suggests an alteration in pyrimidine metabolism (Weljie et al.2007), and in agreement with a previous study (Chen et al.2010) reporting an increased level of pyrimidines in gastric cancer mice.
Spermidine improves gut barrier integrity and gut microbiota function in diet-induced obese mice
Published in Gut Microbes, 2020
Lingyan Ma, Yinhua Ni, Zhe Wang, Wenqing Tu, Liyang Ni, Fen Zhuge, Aqian Zheng, Luting Hu, Yufeng Zhao, Liujie Zheng, Zhengwei Fu
Polyamines are involved in various biological processes and therefore have important implications for human health, especially for intestinal maturation and immune system differentiation and development.22 The biosynthesis of polyamines tends to decrease with age,23,24 and this is the reason why dietary polyamines are of importance in aged populations. Consistently, spermidine content is decreased during aging in both humans and mice, and its supplementation extends the lifespan of mice and protects against cardiovascular diseases.25,26 In addition, cohort study indicated that higher spermidine intake is linked to lower mortality.27 Although several studies have demonstrated the role of spermidine in metabolic syndrome-related diseases, including liver diseases19,20 and obesity,21 the relationship between spermidine intake and the incidence of metabolic syndrome remains unclear. Here, we found that daily spermidine intake was negatively correlated with obesity phenotypes, which serves as a theoretical basis for the establishment of recommended levels of spermidine intake for individuals with obesity.