Thus, cellular respiration yields approximately 38 ATP molecules from one glucose molecule Figure 1 Adenosine triphosphate consists of phosphate, ribose, and adenosine groups that are connected through two high-energy phosphoanhydride bonds within the molecule. Figure 2 From the high energy bonds among the phosphate group, ATP is produced. As a pentose sugar, D-ribose has five carbons in its ring structure; the chemical structure Figure 3 , and the molecular weight is An image of the chemical structure of D-Ribose which is a pentose monosaccharide simple sugar.
Ribose is a naturally occurring five-carbon sugar produced in the body through the PPP, a metabolic pathway parallel to glycolysis that generates nicotinamide adenine dinucleotide phosphate NADPH , pentoses, and ribose 5-phosphate.
The PPP is a slow process that requires an enzyme called glucosephosphate dehydrogenase GPDH that is often in short supply within the cells Figure 4. This enzyme can have limited expression in the myocardial cells with cardiac disease leading to significant delay in the production of ribose There are two main pathways — the de novo and salvage—for the synthesis of nucleotides. Using the 5-phosphoribo-sylpyrophosphate PRPP , the de novo pathway enzymes build purine and pyrimidine nucleotides from the beginning of the process with ribose.
This pathway is much slower than the salvage pathway in which preformed ribose allows the cells to quickly and efficiently recycle the ATP end products. Consequently, ribose is crucial for both the de novo and salvage pathways 37 — In certain pathologic conditions such as heart failure, cellular energy deficiency exists in myocardial mitochondria.
The reduction in ATP production is directly correlated with the decreased supply of D-ribose in the mitochondria. This may be related to the limited expression of the GPDH enzyme in myocardium that can significantly interrupt the production of ribose. Several studies have shown that augmenting D-ribose following myocardial ischemia improves mitochondrial function by increasing myocardial ATP production Administering supplemental D-ribose circumvents the enzymatic step to assist with replenishing ATP levels in cells.
In purine metabolism, D-glucose is transformed to both D-ribosephosphate and to D-ribosephosphate and then altered to 5-phospho-D-ribose 1-pyrophsophate PRPP for the synthesis of purine and pyrimidine Figure 5. Supplemental D-ribose bypasses the upper part of the pentose pathway and is an alternative source for 5-phospho-D-ribose 1-pyrophosphate PRPP.
D-ribose has been used both orally and intravenously in patients for many different pathologic conditions such as chronic fatigue syndrome 41 , fibromyalgia 42 , and myocardial dysfunction It is often used to improve athletic performance and reduce symptoms of cramping, pain, and stiffness following exercise Under different pathologic conditions, ATP, ADP, and adenosine monophosphate are degraded and not available for energy production.
Supplemental D-ribose has been shown to enhance recovery of ATP levels and reduce cellular injury in humans and animals 9 , A study by Pliml et al.
They hypothesized that supplemental D-ribose increased ATP metabolism and assisted with restoring cardiac energy metabolism Another group of investigators found that daily oral D-ribose significantly improved left a trial function in congestive heart failure patients. Supplemental D-ribose can be purchased in a dry powder form, and the recommended dose ranges from 5 to 15 grams per day and not by body mass units The powder is mixed in a non-carbonated drink and has a sweet taste.
It is readily metabolized if consumed within 30 minutes after being mixed in fluid. The side effects are minimal, but patients have reported mild diarrhea, slight nausea, and stomach discomfort that was reduced by consuming the drink with food 45 — There had been some concerns about the safety of ribose therapy related to the inhibitory effects of ribose on cell proliferation in vitro.
However, Pliml et al. They found no significant inhibition of human lymphocyte proliferation in vitro in mitogen-stimulated cells and no evidence that ribose therapy was harmful to human cells Mitochondria regulate a multitude of metabolic and signaling pathways, but their primary function is the production of ATP. When mitochondrial function is compromised, there can be a reduced efficiency of cellular respiration and thus a loss of ATP production.
D-ribose is an ATP substrate naturally occurring within cells. When nucleotides are reduced, supplemental D-ribose has been shown to be useful in enhancing the recovery of these energy molecules. Thus, D-ribose supplementation may help to return adenine nucleotides to the cell and thereby serve as a potential therapeutic option for various pathophysiologic conditions. National Center for Biotechnology Information , U. Adv Biosci Clin Med. Author manuscript; available in PMC May Diane E.
Mahoney , 1 John B. Pierce , 1 James L. Vacek , 2 Richard L. Clancy , 1 Andrew J. Sauer , 3 and Janet D. Pierce 1. John B. John T. James L. Richard L. Andrew J. Janet D. Author information Copyright and License information Disclaimer. Corresponding Author: Amanda Thimmesch, ude. Copyright notice. See other articles in PMC that cite the published article. Abstract Mitochondria are important organelles referred to as cellular powerhouses for their unique properties of cellular energy production.
Mitochondria Mitochondria are highly dynamic double membrane-bound organelles cellular components found in the cytoplasm of most eukaryotic cells, those cells that contain a nucleus 11 — Cellular Respiration Cellular respiration is a series of biochemical reactions within mitochondria that results in ATP production Open in a separate window.
Figure 1. Figure 2. Figure 3. Figure 4. The relationship of the pentose phosphate pathway to stages of cellular respiration. Supplemental D-ribose In certain pathologic conditions such as heart failure, cellular energy deficiency exists in myocardial mitochondria. Figure 5. Funding: None. Footnotes Conflicts of interest: None.
References 1. Martin-Fernandez B, Gredilla R. Mitochondria and oxidative stress in heart aging. Age Dordr ; 38 — Mitochondrial energetics and therapeutics. Annu Rev Pathol. Schapira AH. Mitochondrial disease. Nicolson GL. Integr Med Encinitas ; 13 — Mitochondrial Metabolism in Aging Heart. Circ Res. Lane N. Energetics and genetics across the prokaryote-eukaryote divide. Biol Direct. The rise of mitochondria in medicine.
Chinnery PF, Hudson G. Mitochondrial genetics. Br Med Bull. D-Ribose as a supplement for cardiac energy metabolism. J Cardiovasc Pharmacol Ther. Herrick J, St Cyr J. Ribose in the heart.
J Diet Suppl. Mitochondrial quality control pathways: PINK1 acts as a gatekeeper. Biochem Biophys Res Commun. Ettema TJ. Evolution: Mitochondria in the second act. Agrawal A, Mabalirajan U. Rejuvenating cellular respiration for optimizing respiratory function: targeting mitochondria.
Selective removal of mitochondria via mitophagy: distinct pathways for different mitochondrial stresses. Biochim Biophys Acta. Mitochondria are the powerhouses of immunity. Nat Immunol. Mitochondrially derived peptides as novel regulators of metabolism. J Physiol. One cup of skim milk contains 0. An ounce of cheddar cheese has 0. Eggs and dairy products also boast calcium, potassium, vitamin D and protein. These nutrients contribute to healthy bone mass and low blood pressure. Opt for low-fat or fat-free milk and cheese.
Other options are high in fat and cholesterol, which can raise your bad cholesterol and contribute to heart disease. Certain vegetables provide you with a dose of ribose or riboflavin. One-half cup of spinach holds 0. Vegetables are also an excellent source of potassium, fiber, folate and vitamins A and C.
Roast asparagus or broccoli and toss it over pasta or eat it as a side dish, add spinach to sandwiches and soups, or chop any of the three and add it to an omelet for an energizing dose of ribose to start your day.
In the United States, food companies enrich wheat flour and breads with riboflavin. According to the Linus Pauling Institute, 1 cup of wheat puffed cereal contains 0. A slice of white bread contains 0. The dietary fiber in whole grains, however, can prevent constipation, reduce your cholesterol levels and lower your risk of heart disease, obesity and Type 2 diabetes. Nutrition Nutrition Basics Carbs. By Michelle Fisk. Michelle Fisk.
Michelle Fisk began writing professionally in
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