Caffeine Molecule

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A Caffeine Molecule is a methlzanthine.

References

2022

  • (Wikipedia, 2022) ⇒ https://en.wikipedia.org/wiki/Caffeine Retrieved:2022-8-21.
    • Caffeine is a central nervous system (CNS) stimulant of the methylxanthine class.[1] It is used as a cognitive enhancer, increasing alertness and attentional performance.[2] [3] Caffeine acts by blocking binding of adenosine to the adenosine A1 receptor, which enhances release of the neurotransmitter acetylcholine. Caffeine also increases cyclic AMP levels through nonselective inhibition of phosphodiesterase.

      Caffeine is a bitter, white crystalline purine, a methylxanthine alkaloid, and is chemically related to the adenine and guanine bases of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). It is found in the seeds, fruits, nuts, or leaves of a number of plants native to Africa, East Asia and South America,[4] and helps to protect them against herbivores and from competition by preventing the germination of nearby seeds,[5] as well as encouraging consumption by select animals such as honey bees.[6] The best-known source of caffeine is the coffee bean, the seed of the Coffea plant. People may drink beverages containing caffeine to relieve or prevent drowsiness and to improve cognitive performance. To make these drinks, caffeine is extracted by steeping the plant product in water, a process called infusion. Caffeine-containing drinks, such as coffee, tea, and cola, are consumed globally in high volumes. In 2020, almost 10 million tonnes of coffee beans were consumed globally. Caffeine is the world's most widely consumed psychoactive drug.[7] Unlike most other psychoactive substances, caffeine remains largely unregulated and legal in nearly all parts of the world. Caffeine is also an outlier as its use is seen as socially acceptable in most cultures and even encouraged in others, particularly in the Western world.

      Caffeine can have both positive and negative health effects. It can treat and prevent the premature infant breathing disorders bronchopulmonary dysplasia of prematurity and apnea of prematurity. Caffeine citrate is on the WHO Model List of Essential Medicines.[8] It may confer a modest protective effect against some diseases, including Parkinson's disease.[9] Some people experience sleep disruption or anxiety if they consume caffeine, but others show little disturbance. Evidence of a risk during pregnancy is equivocal; some authorities recommend that pregnant women limit caffeine to the equivalent of two cups of coffee per day or less.[10] [11] Caffeine can produce a mild form of drug dependence – associated with withdrawal symptoms such as sleepiness, headache, and irritability – when an individual stops using caffeine after repeated daily intake.[12][13][14] Tolerance to the autonomic effects of increased blood pressure and heart rate, and increased urine output, develops with chronic use (i.e., these symptoms become less pronounced or do not occur following consistent use). Caffeine is classified by the US Food and Drug Administration as generally recognized as safe. Toxic doses, over 10 grams per day for an adult, are much higher than the typical dose of under 500 milligrams per day. The European Food Safety Authority reported that up to 400 mg of caffeine per day (around 5.7 mg/kg of body mass per day) does not raise safety concerns for non-pregnant adults, while intakes up to 200 mg per day for pregnant and lactating women do not raise safety concerns for the fetus or the breast-fed infants. A cup of coffee contains 80–175 mg of caffeine, depending on what "bean" (seed) is used, how it is roasted (darker roasts have less caffeine), and how it is prepared (e.g., drip, percolation, or espresso). Thus it requires roughly 50–100 ordinary cups of coffee to reach the toxic dose. However, pure powdered caffeine, which is available as a dietary supplement, can be lethal in tablespoon-sized amounts.

  1. ↑ Nehlig A, Daval JL, Debry G (1992). “Caffeine and the central nervous system: mechanisms of action, biochemical, metabolic and psychostimulant effects". Brain Research. Brain Research Reviews. 17 (2): 139–170. doi:10.1016/0165-0173(92)90012-B. PMID 1356551. S2CID 14277779.
  2. ↑ Nehlig A, Daval JL, Debry G (1992). “Caffeine and the central nervous system: mechanisms of action, biochemical, metabolic and psychostimulant effects". Brain Research. Brain Research Reviews. 17 (2): 139–170. doi:10.1016/0165-0173(92)90012-B. PMID 1356551. S2CID 14277779.
  3. ↑ Wood S, Sage JR, Shuman T, Anagnostaras SG (January 2014). "Psychostimulants and cognition: a continuum of behavioral and cognitive activation". Pharmacological Reviews. 66 (1): 193–221. doi:10.1124/pr.112.007054. PMC 3880463. PMID 24344115.
  4. ↑ Caballero B, Finglas P, Toldra F (2015). Encyclopedia of Food and Health. Elsevier Science. p. 561. ISBN 978-0-12-384953-3. Retrieved 17 June 2018.
  5. ↑ Myers RL (2007). The 100 Most Important Chemical Compounds: A Reference Guide. Greenwood Press. p. 55. ISBN 978-0-313-33758-1. Retrieved 17 June 2018.
  6. ↑ Wright GA, Baker DD, Palmer MJ, Stabler D, Mustard JA, Power EF, Borland AM, Stevenson PC (March 2013). "Caffeine in floral nectar enhances a pollinator's memory of reward". Science. 339 (6124): 1202–4. Bibcode:2013Sci...339.1202W. doi:10.1126/science.1228806. PMC 4521368. PMID 23471406.
  7. ↑ Burchfield G (1997). Meredith H (ed.). "What's your poison: caffeine". Australian Broadcasting Corporation. Archived from the original on 26 July 2009. Retrieved 15 January 2014.
  8. ↑ WHO Model List of Essential Medicines (PDF) (18th ed.). World Health Organization. October 2013 [April 2013]. p. 34 [p. 38 of pdf]. Retrieved 23 December 2014.
  9. ↑ Qi H, Li S (April 2014). “Dose-response meta-analysis on coffee, tea and caffeine consumption with risk of Parkinson's disease". Geriatrics & Gerontology International. 14 (2): 430–9. doi:10.1111/ggi.12123. PMID 23879665. S2CID 42527557.
  10. ↑ Jahanfar S, Jaafar SH, et al. (Cochrane Pregnancy and Childbirth Group) (June 2015). “Effects of restricted caffeine intake by mother on fetal, neonatal and pregnancy outcomes". The Cochrane Database of Systematic Reviews (6): CD006965. doi:10.1002/14651858.CD006965.pub4. PMID 26058966.
  11. ↑ American College of Obstetricians and Gynecologists (August 2010). “ACOG CommitteeOpinion No. 462: Moderate caffeine consumption during pregnancy". Obstetrics and Gynecology. 116 (2 Pt 1): 467–8. doi:10.1097/AOG.0b013e3181eeb2a1. PMID 20664420.
  12. ↑ Malenka RC, Nestler EJ, Hyman SE (2009). “Chapter 15: Reinforcement and Addictive Disorders". In Sydor A, Brown RY (eds.). Molecular Neuropharmacology: A Foundation for Clinical Neuroscience (2nd ed.). New York: McGraw-Hill Medical. p. 375. ISBN 978-0-07-148127-4. Long-term caffeine use can lead to mild physical dependence. A withdrawal syndrome characterized by drowsiness, irritability, and headache typically lasts no longer than a day. True compulsive use of caffeine has not been documented".
  13. ↑ American Psychiatric Association (2013). "Substance-Related and Addictive Disorders" (PDF). American Psychiatric Publishing. pp. 1–2. Archived from the original (PDF) on 15 August 2015. Retrieved 10 July 2015. Substance use disorder in DSM-5 combines the DSM-IV categories of substance abuse and substance dependence into a single disorder measured on a continuum from mild to severe. ... Additionally, the diagnosis of dependence caused much confusion. Most people link dependence with "addiction" when in fact dependence can be a normal body response to a substance. ... DSM-5 will not include caffeine use disorder, although research shows that as little as two to three cups of coffee can trigger a withdrawal effect marked by tiredness or sleepiness. There is sufficient evidence to support this as a condition, however it is not yet clear to what extent it is a clinically significant disorder."
  14. ↑ Juliano LM, Griffiths RR (October 2004). “A critical review of caffeine withdrawal: empirical validation of symptoms and signs, incidence, severity, and associated features". Psychopharmacology. 176 (1): 1–29. doi:10.1007/s00213-004-2000-x. PMID 15448977. S2CID 5572188. Results: Of 49 symptom categories identified, the following 10 fulfilled validity criteria: headache, fatigue, decreased energy/ activeness, decreased alertness, drowsiness, decreased contentedness, depressed mood, difficulty concentrating, irritability, and foggy/not clearheaded. In addition, flu-like symptoms, nausea/vomiting, and muscle pain/stiffness were judged likely to represent valid symptom categories. In experimental studies, the incidence of headache was 50% and the incidence of clinically significant distress or functional impairment was 13%. Typically, onset of symptoms occurred 12–24 h after abstinence, with peak intensity at 20–51 h, and for a duration of 2–9 days."
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