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Vinpocetine
Vinpocetine is derived from vincamine, the major indole alkaloid of the periwinkle plant. Vinpocetine has been used for many years in Europe to enhance memory and mental function by increasing neuronal firing rate. No toxic effects have been seen from vinpocetine use at levels far above therapeutic dosages. Vinpocetine taken orally is easily absorbed.137,138 When taken orally, vinpocetine can:
1 tablet
contains: Other ingredients: dicalcium phosphate, cellulose, stearic acid, magnesium stearate. Dosage and
use
Caution:
LE Magazine February
2006 Vinpocetine is a novel dietary supplement derived from the lesser periwinkle plant Vinca minor. Better known in the US as an attractive garden border than a health aid, this plant has many useful derivatives that promote better health and quality of life. Since it was first synthesized in the late 1960s, vinpocetine has been used to maintain and improve brain health and cognition. It is widely used in Japan and many European countries to treat a number of cerebrovascular diseases. As a dietary supplement, vinpocetine offers potential neuroprotective effects as well. To understand how and why this phytonutrient works, it is important to understand a bit about normal and abnormal blood flow in the brain. Nourishing
the Brain Fortunately, the brain is equipped with an excellent circulatory system of its own. Not unlike a modern jetliner with its multiple power backup systems, the brain has four major arteries to keep blood flowing. The two carotid arteries in the sides of the neck provide most of the blood flow to the front and top of the brain, while the vertebral arteries, which climb up through the spinal column, join together with parts of the carotids to form the Circle of Willis. This circle is critical, as it is the only area of the body where all four blood vessels join, allowing blood to be shunted to areas where it is needed, even if one of the major vessels becomes blocked. Like the bodys other blood vessels, the cerebral blood vessels suffer changes over time that can cause them to narrow. Atherosclerosis, or the accumulation of fat-laden, calcified plaque, is one of the most common causes of narrowing of the cerebral arteries. Chronic high blood pressure is another cause, as the steady pounding of high-pressure blood causes the muscular layer of the vessels to enlarge. With advancing age, blood vessels lose some of their elasticity as well, making it difficult for them to maintain and regulate blood flow. Finally, characteristics of blood itself can significantly affect its flow through brain blood vessels. Elevated levels of red blood cells, as occurs in dehydration and certain lung and kidney diseases, can make the blood thicker and more resistant to easy flow. Red blood cells and platelets also need to remain flexible to slip through tiny capillary openings and reach the tissue. Blood cell membranes lose flexibility under the influence of free radicals that oxidize some of their component lipids. Vinpocetines
Effects on Brain Health Vinpocetine inhibits an enzyme called phosphodiesterase type 1 (PDE1) while reducing intracellular calcium levels, both of which normally cause smooth muscle in blood vessels to contract and narrow the diameter of the vessels. Inhibition of PDE1 and calcium thus allows brain blood vessels to relax and increases the amount of blood flowing through them.2-5 By inhibiting PDE1, as well as through its antioxidant properties,6-8 vinpocetine reduces the viscosity, or stickiness, of red blood cells and platelets.9-13 This allows blood to flow more easily through narrowed vessels, and may help to protect brain tissues in the event of transient loss of blood pressure, when the tissues might otherwise experience insufficient flow (the so-called watershed stroke caused by hypoperfusion). If blood flow to a region of the brain drops enough to cause cellular damage, there is still opportunity to protect nerve cells from both the immediate injury and the oxidant stress that follows when blood flow returns. Vinpocetine is a sodium channel blocker that may protect the cells from this reperfusion injury by preventing the accumulation of sodium in injured brain cells.7,14 This effect may also contribute to preserving brain cells ability to restructure themselves after an injury and to rapidly restore cognitive function.8 Since 1978, vinpocetine has been commonly used in many countries to treat cerebral vascular diseases.15,16 It is currently approved for use in tablet form in 47 countries.17 The evidence for its use is strongest in the treatment of chronic cerebral vascular ischemia, though growing evidence suggests that it may be beneficial in treating or preventing acute ischemic strokes and various forms of dementia. Chronic
Cerebral Vascular Ischemia These physiological effects seem to correlate with actual clinical improvements as well. In an early double-blind, placebo-controlled trial of vinpocetine in the treatment of chronic vascular ischemia, supplemented patients scored better on a battery of cognitive measures such as the Clinical Global Impression scale, the Sandoz Clinical Assessment-Geriatric scale, and the Mini-Mental Status Questionnaire. No serious side effects were found in this study.19 In a much larger randomized, placebo-controlled trial, patients who took 30 or 60 mg per day of oral vinpocetine for 16 weeks showed marked improvements on the Clinical Global Impression scale and on cognitive performance tests. Patients taking vinpocetine also demonstrated lower severity of illness in that study.20 A 2005 study examined vinpocetines effects on cognition and brain blood flow. Although the study was relatively small, with only 14 subjects taking vinpocetine and 12 taking placebo, its results suggest that blood vessel diameter was significantly larger in the vinpocetine group. The investigators also reported that vinpocetine users did not have any worsening on a test of short-term memory over the three months following the trial, whereas the placebo patients did.21 Acute Ischemic
Stroke More recently, however, in a group of acute ischemic stroke patients, a single IV dose of 20 mg of vinpocetine was shown to increase brain perfusion and oxygen extraction compared to placebo.22 Laboratory rats given vinpocetine 30 minutes after induced ischemic stroke had a 42% reduction in the size of the damaged area compared with untreated animals.23 The same authors report significant, dose-dependent protection from short- and long-term neurotoxicity caused by the excitatory amino acids glutamate and N-methyl-D-aspartic acid (NMDA). These data would seem to support a role for vinpocetine in acute treatment of stroke, and might be the basis for recommending its regular use in patients at high risk for acute stroke. A small, single-blind trial of IV vinpocetine within 72 hours of acute stroke onset showed that the risk of a poor outcome was reduced by 30-60% in the treated group. The treated group also had better scores on the National Institutes of Health Stroke Scale at a three-month follow-up evaluation. No significant adverse results were seen, and the authors concluded by recommending a full-scale, double-blind, placebo-controlled trial of vinpocetine treatment in acute ischemic stroke.24 Dementia
and Alzheimers Promising evidence from the laboratory suggests that vinpocetine protects brain tissue from the oxidative stress caused by the Alzheimers protein known as amyloid beta or Abeta.27 Because vinpocetine also blocks the NMDA receptors that are thought to be involved in the genesis of Alzheimers disease,28 vinpocetine supplements have a potential role in preventing Alzheimers. Uses for
Urinary Incontinence Initial clinical data suggested that vinpocetine might be helpful in patients with urgency, urge incontinence, and possibly other kinds of incontinence.11 In a small trial among 19 patients, 58% reported improvements in clinical symptoms or bladder function tests.35 Vinpocetine has been recommended in several recent reviews of substances helpful in controlling female urinary incontinence.36,37 Summary 2. Szakall S, Boros I, Balkay L, et al. Cerebral effects of a single dose of intravenous vinpocetine in chronic stroke patients: a PET study. J Neuroimaging. 1998 Oct;8(4):197-204. 3. Szilagyi G, Nagy Z, Balkay L, et al. Effects of vinpocetine on the redistribution of cerebral blood flow and glucose metabolism in chronic ischemic stroke patients: a PET study. J Neurol Sci. 2005 Mar 15;229-230:275-84. 4. Vas A, Gulyas B, Szabo Z, et al. Clinical and non-clinical investigations using positron emission tomography, near infrared spectroscopy and transcranial Doppler methods on the neuroprotective drug vinpocetine: a summary of evidences. J Neurol Sci. 2002 Nov 15;203-204:259-62. 5. Wu SN. Large-conductance Ca2+- activated K+ channels:physiological role and pharmacology. Curr Med Chem. 2003 Apr;10(8):649-61. 6. Stolc S. Indole derivatives as neuroprotectants. Life Sci. 1999;65(18-19):1943-50. 7. Bonoczk P, Gulyas B, dam-Vizi V, et al. Role of sodium channel inhibition in neuroprotection: effect of vinpocetine. Brain Res Bull. 2000 Oct;53(3):245-54. 8. Lendvai B, Zelles T, Rozsa B, Vizi ES. A vinca alkaloid enhances morphological dynamics of dendritic spines of neocortical layer 2/3 pyramidal cells. Brain Res Bull. 2003 Jan 15;59(4):257-60. 9. Chiu PJ, Tetzloff G, Ahn HS, Sybertz EJ. Comparative effects of vinpocetine and 8-Br-cyclic GMP on the contraction and 45Ca-fluxes in the rabbit aorta. Am J Hypertens. 1988 Jul;1(3 Pt 1):262-8. 10. Jones OM, Brading AF, McC Mortensen NJ. Phosphodiesterase inhibitors cause relaxation of the internal anal sphincter in vitro. Dis Colon Rectum. 2002 Apr;45(4):530-6. 11. Truss MC, Stief CG, Uckert S, et al. Phosphodiesterase 1 inhibition in the treatment of lower urinary tract dysfunction: from bench to bedside. World J Urol. 2001 Nov;19(5):344-50. 12. Mancina R, Filippi S, Marini M, et al. Expression and functional activity of phosphodiesterase type 5 in human and rabbit vas deferens. Mol Hum Reprod. 2005 Feb;11(2):107-15. 13. Szapary L, Horvath B, Alexy T, et al. Effect of vinpocetin on the hemorheologic parameters in patients with chronic cerebrovascular disease. Orv Hetil. 2003 May 18;144(20):973-8. 14. Molnar P, Erdo SL. Vinpocetine is as potent as phenytoin to block voltage-gated Na+ channels in rat cortical neurons. Eur J Pharmacol. 1995 Feb 6;273(3):303-6. 15. Bereczki D, Fekete I. A systematic review of vinpocetine therapy in acute ischaemic stroke. Eur J Clin Pharmacol. 1999 Jul;55(5):349-52. 16. Karpati E, Biro K, Kukorelli T. Investigation of vasoactive agents with indole skeletons at Richter Ltd. Acta Pharm Hung. 2002;72(1):25-36. 17. Anon. Vinpocetine. Monograph. Altern Med Rev. 2002 Jun;7(3):240-3. 18. Hadjiev D. Asymptomatic ischemic cerebrovascular disorders and neuroprotection with vinpocetine. Ideggyogy Sz. 2003 May 20;56(5-6):166-72. 19. Balestreri R, Fontana L, Astengo F. A double-blind placebo controlled evaluation of the safety and efficacy of vinpocetine in the treatment of patients with chronic vascular senile cerebral dysfunction. J Am Geriatr Soc. 1987 May;35(5):425-30. 20. Hindmarch I, Fuchs HH, Erzigkeit H. Efficacy and tolerance of vinpocetine in ambulant patients suffering from mild to moderate organic psychosyndromes. Int Clin Psychopharmacol. 1991;6(1):31-43. 21. Kemeny V, Molnar S, Andrejkovics M, Makai A, Csiba L. Acute and chronic effects of vinpocetine on cerebral hemodynamics and neuropsychological performance in multi-infarct patients. J Clin Pharmacol. 2005 Sep;45(9):1048-54. 22. Bonoczk P, Panczel G, Nagy Z. Vinpocetine increases cerebral blood flow and oxygenation in stroke patients: a near infrared spectroscopy and transcranial Doppler study. Eur J Ultrasound. 2002 Jun;15(1-2):85-91. 23. Dezsi L, Kis-Varga I, Nagy J, Komlodi Z, Karpati E. Neuroprotective effects of vinpocetine in vivo and in vitro. Apovincaminic acid derivatives as potential therapeutic tools in ischemic stroke. Acta Pharm Hung. 2002;72(2):84-91. 24. Feigin VL, Doronin BM, Popova TF, Gribatcheva EV, Tchervov DV. Vinpocetine treatment in acute ischaemic stroke: a pilot single-blind randomized clinical trial. Eur J Neurol. 2001 Jan;8(1):81-5. 25. Nagy Z, Vargha P, Kovacs L, Bonoczk P. Meta-analysis of Cavinton. Praxis. 1988 September 15;7(9):63-8. 26. Szatmari SZ, Whitehouse PJ. Vinpocetine for cognitive impairment and dementia. Cochrane Database Syst Rev. 2003;(1):CD003119. 27. Pereira C, Agostinho P, Oliveira CR. Vinpocetine attenuates the metabolic dysfunction induced by amyloid beta-peptides in PC12 cells. Free Radic Res. 2000 Nov;33(5):497-506. 28. Kiss B, Cai NS, Erdo SL. Vinpocetine preferentially antagonizes quisqualate/AMPA receptor responses: evidence from release and ligand binding studies. Eur J Pharmacol. 1991 Dec 10;209(1-2):109-12. 29. Pilgramm M, Schumann K. Need for rheologically active, vasoactive and metabolically active substances in the initial treatment of acute acoustic trauma. HNO. 1986 Oct;34(10):424-8. 30. Konopka W, Zalewski P, Olszewski J, Olszewska-Ziaber A, Pietkiewicz P. Treatment results of acoustic trauma. Otolaryngol Pol. 1997;51 Suppl 25:281-4. 31. Maliavina US, Ovchinnikov I, Fasenko VP, et al. Cavinton prevention of neurosensory hypoacousis in patients with different forms of tuberculosis. Vestn Otorinolaringol. 2003;(3):35-40. 32. Qiu Y, Kraft P, Craig EC, Liu X, Haynes-Johnson D. Cyclic nucleotide phosphodiesterases in rabbit detrusor smooth muscle. Urology. 2002 Jan;59(1):145-9. 33. Qiu Y, Kraft P, Craig EC, Liu X, Haynes-Johnson D. Identification and functional study of phosphodiesterases in rat urinary bladder. Urol Res. 2001 Dec;29(6):388-92. 34. Uckert S, Stief CG, Odenthal KP, et al. Comparison of the effects of various spasmolytic drugs on isolated human and porcine detrusor smooth muscle. Arzneimittelforschung. 1998 Aug;48(8):836-9. 35. Truss MC, Stief CG, Uckert S, et al. Initial clinical experience with the selective phosphodiesterase-I isoenzyme inhibitor vinpocetine in the treatment of urge incontinence and low compliance bladder. World J Urol. 2000 Dec;18(6):439-43. 36. Hampel C, Gillitzer R, Pahernik S, Melchior SW, Thuroff JW. Drug therapy of female urinary incontinence. Urologe A. 2005 Mar;44(3):244-55. 37. Alberti C. Bladder and cavernous contractility and relaxation among intracellular messengers, changes in sarcoplasmatic free calcium and phosphodiesterase activity. Arch Ital Urol Androl. 2000 Jun;72(2):75-82. 38. Tsuda K, Kinoshita
Y, Nishio I. Synergistic role of progesterone and nitric oxide in the
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These statements have not been evaluated by the FDA. These products are not intended to diagnose, treat, cure, or prevent any disease
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