lemon balm, oxidative stress and infection, CYB5R, molybdenum - brief notes

Lemon balm (Melissa officinalis) methanolic extract was shown to have antiviral activity in vitro against enterovirus 71 - attributed to the antioxidant constituent rosmarinic acid.

https://www.nature.com/articles/s41598-017-12388-2

"Several lines of evidence support the notion that the redox status of host affects viral pathogenesis26. We have previously shown that EV71 infection induces oxidative stress, which in turn promotes viral replication27,28. Treatment with antioxidants, such as N-acetylcysteine (NAC) or mito-Tempo, suppresses EV71 replication27,28,29. Natural antioxidants, epigallocatechin gallate (EGCG) and gallocatechin gallate (GCG), in green tea have antiviral activity, which correlates well with their antioxidant capacity30. It is probable that the antiviral activities of natural products may be partly attributed to their antioxidative activities."

Review article on redox biology of respiratory viral infections:

https://pubmed.ncbi.nlm.nih.gov/30049972/

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Molybdenum deficiency resulted in reduced CYB5R  activity in a rat study.

Yuan, Yang, Wang Fan, Li Guangsheng, and Kang Deren. “Study on the Relation between Molybdenum and Methemoglobin Reductase: Low Molybdenum Diet Experiment in Rats.” [Ying Yang Xue Bao] Acta Nutrimenta Sinica 16, no. 2 (January 1, 1994): 111–14. http://europepmc.org/article/CBA/273954.

"Molybdenum deficiency of rats was produced by low molybdenum diet. The NADH-cytochrome b_(5)-methemoglobin reductase activity in erythrocyte was in increased significantly in the rats supplemented with 1.0 and 5.0mg/kg Mo as NaMoO_(4) to the diet. The concentrations of molybdenum in erythrocytes of rats of supplemented groups were significantly higher than those of low molybdenum group. The concentration of molybdenum in erythrocytes was significantly correlated with NADH-cytochrome b_(5)-methemoglobin redutase activity in rats supplemented with 0.1 and 1.0 mg/kg molybdenum."

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Cytochrome b5 reductase and the control of lipid metabolism and healthspan

https://pubmed.ncbi.nlm.nih.gov/28721264/

"Cytochrome b5 reductases are a family of flavoproteins that catalyze the reduction of coenzyme Q and cytochrome b5 using NADH as an electron donor in a one-electron transfer reaction.8 This family is composed of only a single member in Drosophila melanogaster (CYB5R) and four members in mammals, known as CYB5R1–4. These proteins exhibit antioxidant properties, as evidenced by an increase in reduced coenzyme Q content coupled with NADH oxidation.8 Cytochrome b5 reductases are expressed in a number of subcellular compartments, including the endoplasmic reticulum, the mitochondrial outer membrane and the plasma membrane, to control the redox state of the cells.5 CYB5R participates in a variety of metabolic conversions, including the elongation and desaturation of fatty acids, cholesterol biosynthesis and cytochrome P450-mediated mono-oxygenation, and represents a major antioxidant in response to vitamin E deficiency.9 The increase in NADH oxidation by CYB5R activity has been linked to the activation of the sirtuin family of NAD+-dependent histone deacetylases,10,11 and therefore CYB5R may have an important role in the regulation of metabolic pathways associated with healthspan and aging.12       

...

In summary, this cross-species study along with our previous report in yeast indicate that CYB5R is an important and conserved modulator of healthspan-associated pathways through improved control of energy homeostasis and mitochondrial bioenergetic efficiency. We demonstrated that CYB5R3 overexpression also confers partial protection against xenobiotic-induced liver cancer in laboratory mice. Our findings warrant the development of new strategies aimed at targeting CYB5R for metabolism regulation and treatment of age-associated pathologies."



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African American men were found to have reduced CYB5R activity relative to Caucasian American men:

https://pubmed.ncbi.nlm.nih.gov/9549232/

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https://emedicine.medscape.com/article/204178-overview#a4

"Higher gastric pH in infants may facilitate bacterial proliferation, resulting in increased conversion of dietary nitrates to nitrites.

An association between methemoglobinemia and acute gastroenteritis in infants has been noted in several studies. This may be due to acidosis from loss of stool bicarbonate, which impairs the already immature function of the methemoglobin reductase system in these young patients ."

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Freshwater aquarium fish can suffer from methemoglobinemia, called 'brown blood disease', as a result of 'new tank syndrome' which is nitrite accumulation due to lack of nitrifying bacteria. Saltwater fish are less susceptible as chloride can prevent uptake of nitrite by the gills.

https://www.addl.purdue.edu/newsletters/1998/spring/nitrate.shtml

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In suspensions of erythrocytes, chloride prolongs methemoglobinemia, while bicarbonate stimulates reduction of methemoglobin:

https://www.sciencedirect.com/science/article/abs/pii/000629526890364X







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