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Biochemical Markers in Ophthalmology
Published in Ching-Yu Cheng, Tien Yin Wong, Ophthalmic Epidemiology, 2022
Abdus Samad Ansari, Pirro G. Hysi
Neurodegeneration, elevated IOP, and oxidative stress are among the factors leading to disease development and progression. Metabolomic studies have looked to evaluate how we can better identify metabolic changes in these patients. Markers for oxidative stress have been found in both serum and aqueous samples. These include 2-mercaptoethanesulfonic acid, d-erythronolactone, dehydroascorbic acid, galactose, mannose, pelargonic acid, ribitol, N-acetyl-l-leucine, RAC-glycerol 1-myristate, arginine, 1-oleoyl-RAC-glycerol, and cystathionine [121, 122]. One systematic review identified malonyldialdehyde as one of the best biomarkers for oxidative stress in serum for patients with glaucoma [123]. Other studies have indicated that spermine and spermidine may play a metabolic role in individuals with POAG [122], potentially affecting mitochondrial membrane potential, thus influencing a degree of neuroprotection on the optic nerve. More recently a metabolome-wide association study employing machine learning and Mendelian randomization found that levels of O-methylascorbate, a circulating product of vitamin C metabolism, significantly lowered IOP in subjects from the general population [124].
Plant-Based Natural Products Against Huntington’s Disease: Preclinical and Clinical Studies
Published in Megh R. Goyal, Hafiz Ansar Rasul Suleria, Ademola Olabode Ayeleso, T. Jesse Joel, Sujogya Kumar Panda, The Therapeutic Properties of Medicinal Plants, 2019
Banadipa Nanda, Samapika Nandy, Anuradha Mukherjee, Abhijit Dey
Spermidine (@5 and 10 mg/kg), a potent polyamine with antioxidant and anti-inflammatory properties, attenuated 3-NP-induced striatal toxicity in rats through regulation of oxidative stress, motor coordination, and striatal neurotransmitters levels [46]. Polyamines (including spermidine) are active against age-induced memory impairment (AMI) [121].
Biochemical and Pharmacological Rationales in Radiotracer Design
Published in Lelio G. Colombetti, Principles of Radiopharmacology, 2019
Raymond E. Counsell, Nancy Korn
The polyamines, spermidine and spermine, and their precursor putrescine are ubiquitous in nature. These substances are synthesized from L-ornithine in higher animals according to the pathway shown in Figure 20.
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
Spermidine, a natural polyamine, can either be obtained orally from exogenous dietary sources or be produced by commensal intestinal bacteria and cellular biosynthesis.16 The concentration of spermidine declines in an age-dependent manner and epidemiological studies have revealed that the increased dietary uptake of spermidine reduces overall mortality associated with cardiovascular diseases and cancer.17 The beneficial effects exerted by spermidine on aging and various diseases are mainly attributed to its role as a physiological autophagy inducer in a variety of model organisms.16,18 Recent studies have demonstrated that spermidine treatment protects against liver fibrosis and hepatocarcinogenesis by activating the microtubule-associated protein 1S (MAP1S)-mediated autophagy pathway.19,20 Moreover, spermidine administration attenuated weight gain and the comorbidities of obesity induced by hypercaloric pro-diabetic regimens, and this effect was correlated with autophagy activity in white adipose tissue (WAT).21 However, it is still not clear whether spermidine could protect gut barrier function by inducing autophagy, and how spermidine modifies the gut microbiota and contributes to metabolic improvement remains unresolved.
Nutritional intervention in chronic pain: an innovative way of targeting central nervous system sensitization?
Published in Expert Opinion on Therapeutic Targets, 2020
Jo Nijs, Sevilay Tumkaya Yilmaz, Ömer Elma, Joe Tatta, Patrick Mullie, Luc Vanderweeën, Peter Clarys, Tom Deliens, Iris Coppieters, Nathalie Weltens, Lukas Van Oudenhove, Eva Huysmans, Anneleen Malfliet
Polyamines represent another potential therapeutic target in the area of nutritional interventions for the prevention of post-surgical pain. Polyamines are cationic organic molecules present in all living organisms, with spermidine, spermine, and their precursor putrescine as the main polyamines in mammalian cells [71]. Human gut bacteria synthesize and transport polyamines [71], and polyamine levels increase with inflammation [72]. Polyamines are thought to be involved in the regulation of numerous metabolic and electrophysiological processes in the nervous system, including scavenging of reactive oxygen species, and alteration of polyamine metabolism has been identified in neurodegenerative disease and several types of cancer, resulting in the increased interest of exogenous administration of natural polyamines as innovative treatment [71]. Animal studies support the idea that a polyamine-deficient dietary pattern has analgesic effects on inflammatory pain [73] and reduces pain hypersensitivity [74]. Excitation of N-methyl-D-aspartate (NMDA) receptors is an essential component of the central nervous system sensitization, with polyamines holding the capacity to modulate them [72]. Polyamine-deficient dietary pattern is thought to inhibit tyrosine phosphorylation of the NMDA receptors [72], thereby potentially decreasing the sensitivity of the (central) nervous system.
Intestinal luminal putrescine is produced by collective biosynthetic pathways of the commensal microbiome
Published in Gut Microbes, 2019
Atsuo Nakamura, Takushi Ooga, Mitsuharu Matsumoto
Polyamines, which include putrescine, spermidine, and spermine, are low-molecular-weight organic cations required for structural stability of DNA and RNA, protein synthesis, cell growth, and differentiation.13 Accordingly, polyamines have multiple physiological roles. For example, polyamines suppress inflammation by inhibiting inflammatory cytokine synthesis in macrophages,14 exert antimutagenic effects,15,16 and inhibit aberrant gene methylation.17 In intestinal epithelial cells, polyamines play a role in occludin protein synthesis and stability,18 regulate E-cadherin transcription,19 regulate apoptosis,20 and increase cell proliferation.21 Furthermore, spermidine enhances longevity in bacteria, yeast, worms, and flies by promoting autophagy.22 In mammals, the abundance of polyamines in the body decreases with age,23,24 and the concentration of intestinal luminal polyamines is lower in the elderly.25 Most dietary polyamines are absorbed in the small intestine.26 In contrast, putrescine and spermidine are produced by intestinal bacteria in the colon.27 Recently, Kibe et al.28 demonstrated that administration of arginine, a polyamine precursor, results in a dose-dependent increase in putrescine concentration in the rat and mouse colonic lumen and that increasing polyamine abundance in the mouse colonic lumen delays senescence. Therefore, intestinal bacteria are considered an important source of polyamines in the lower intestinal tract.