Vinpocetine
Vinpocetine is a semi-synthetic derivative alkaloid from the periwinkle plant (Vinca Minor). It is commonly used to treat vascular and cognitive disorders especially in elderly people. For this reason it has undergone extensive research. The studies demonstrate that is clearly has an effect on cognition. All human studies are supportive of this with none against. The mechanism of action appears to be via increasing the blood supply to the brain.
Most beneficial for - Both healthy individuals and those with cognitive problems have demonstrated benefit
Effective dose - 10-60mg daily has shown to be effective
Length of action - Studies indicate that its benefits begin after 2 days and continue with use at least to 16 weeks
Safety - No adverse effect were reported in these studies at the effective doses
Type cognition effected - Memory (including short term memory),
Enhancers - possibly Ginkgo Biloba
Supporting Human Studies
Psychopharmacological effects of vinpocetine in normal healthy volunteers (Subhan et al, 1985)
Twelve healthy female volunteers received vinpocetine (10, 20, 40mg/day) or a placebo over 3 days before performing a battery of psychological and cognitive tests. The 40mg dose of vinpocetine was shown to improve scores on the memory test significantly compared to the placebo group. All other tests (critical flicker fusion, choice reaction time and rating of drug effects) showed no differences between groups.
Possible memory-enhancing properties of vinpocetine (Coleston et al, 2004)
Twelve volunteers received vinpocetine (40mg) or a placebo for two days. They then underwent several cognitive tests. Results showed a significant improvement in short term memory in the vinpocetine group compared to the placebo.
Investigation of the effect of vinpocetine on cerebral blood flow and cognitive functions (Valikovics et al, 2007)
Two groups of patients with mild cognitive impairment or ischemic stroke had cerebral blood flow and cognitive function measured before and after the administration of vinpocetine. The patients took vinpocetine for 12 weeks. At the end of the 12 week cycle cerebral blood flow was significantly increased as was performance on cognitive tests. This was identical in both groups of patients.
Efficacy and tolerance of vinpocetine in ambulant patients suffering from mild to moderate organic psychosyndromes (Hindmarch et al, 1991)
Elderly patients (N=165) with mild to moderate psychosyndromes received vinpocetine (30 or 60mg) or a placebo daily for 16 weeks. Cognitive and mood was evaluated after 16 weeks. The vinpocetine was shown to significantly improve several mood and cognitive factors compared to the placebo. No adverse drug reactions were observed in the vinpocetine group either.
Vinpocetine Effects on Cognitive Impairments Produced by Flunitrazepam (Bhatti et al, 1987)
The effects of pre-treatment with vinpocetine 40 mg, on flunitrazepam-induced impairment of memory, were studied in 8 normal volunteers. Tests of Critical Flicker Fusion Threshold, a Sternberg Memory Scanning Task, along with subjective ratings of drug action were used. Drug effects were found to be modest. Treatment with vinpocetine was associated with improvements in short-term memory processes.
Clinical evidence of the effectiveness of vinpocetine in the treatment of organic psychosyndrome (Blaha et al, 1989)
In this double blind placebo controlled trial 282 patients with mild to moderate psychosyndromes caused by cerebral blood supply disorders randomly received vinpocetine (5, 10 and 20mg) three times per day or a placebo.
Those taking the vinpocetine showed significant improvements in clinical global impression and performance SKT tests compared to the placebo group. Higher doses of vinpocetine showed greater effects.
A double-blind placebo controlled evaluation of the safety and efficacy of vinpocetine in the treatment of patients with chronic vascular senile cerebral dysfunction (Balesteri et al, 1987)
In a double-blind clinical trial vinpocetine was shown to effect significant improvement in 84 57–94 yr old patients with chronic cerebral dysfunction. 42 patients received 10 mg vinpocetine 3 times a day for 30 days, then 5 mg three time a day for 60 days. Matching placebo tablets were given to another 42 patients for the 90-day trial period. Patients taking vinpocetine scored consistently better in all evaluations of the effectiveness of treatment including measurements on the Clinical Global Impression Scale, the Clinical Assessment-Geriatric Scale, and the Mini-Mental Status Questionnaire. No serious side effects were noted.
Vinpocetine increases cerebral blood flow and oxygenation in stroke patients: a near infrared spectroscopy and transcranial Doppler study (Bonoczk et al, 2002)
Forty three patients suffering stroke were randomized to receive either 20mg of vinpocetine intravenously or a placebo. Blood flow and oxygenation were measured in the brain before and after undergoing the treatment. Results of the tests showed that vinpocetine significantly increased both the level of blood flowing into the brain as well as its oxygenation of brain tissue compared to the placebo group.
Supporting Animal Studies
Vinpocetine: Nootropic effects on scopolamine-induced and hypoxia-induced retrieval deficits of a step-through passive avoidance response in rats (DeNoble et al, 1985)
Cognitive impairments were induced in rats using either drugs or hypoxic conditions. Vinpocetine was then administered at varying doses and the effects on cognitive tests observed. Vinpocetine at the peak dose of 20mg/kg prevented drug induced memory deficits. Vinpocetine at 3mg/kg also prevented disruption of passive avoidance retention impaired by hypoxic conditions.
The impairment of long-term potentiation in rats with medial septal lesion and its restoration by cognition enhancers (Molnar et al, 1994)
Rats had their brains lesioned and then underwent test to observe its effect on long term memory formation. The lesion did demonstrate significant reductions in long term memory parameters. Some rats received vinpocetine 1 hour after lesion formation and daily for 6 days thereafter. Vinpocetine completely restored the negative effects caused by the lesion.
Vinpocetine enhances retrieval of a step-through passive avoidance response in rats (DeNoble, 1987)
Rats were studies for the effects of vinpocetine on a passive avoidance task. Vinpocetine administered 60 minutes before testing significantly increased the rats performing the passive avoidance. The range of effective doses was 18-30mg/kg.
Amelioration of intracerebroventricular streptozotocin induced cognitive dysfunction and oxidative stress by vinpocetine — a PDE1 inhibitor (Deshmukh et al, 2009)
Rats were given a drug to induce cognitive decline similar to that in Alzheimer's disease. They then received vinpocetine (5, 10 and 20mg/kg/day) for 21 days. All doses of vinpocetine were found to improve learning and memory in water mazes and passive avoidance tests. Also observed were reductions in oxidative stress as well as improvement in cholinergic function.
Cellular Studies
Idebenone and vinpocetine augment long-term potentiation in hippocampal slices in the guinea pig (Ishihara et al, 1989)
Hippocampal segments of guinea pig brain were cultured with or without vinpocetine. Results showed that the addition of vinpocetine significantly augmented long term potentiation in the hippocampal segments.
Contradictory Studies
None
Combinational Studies
Cognitive effects of a Ginkgo biloba/vinpocetine compound in normal adults: systematic assessment of perception, attention and memory (Polich et al, 2001)
A battery of computerized tests was performed by 24 healthy adults. Half the adults received a ginkgo biloba/vinpocetine supplement and the other half a placebo for 14 days prior to the tests. Those receiving the ginkgo/vinpocetine supplement demonstrated a 50ms response improvement on a test for short term working memory.
Safety Studies
The safety and lack of efficacy of vinpocetine in Alzheimer's disease (Thal et al, 1989)
Fifteen patients with Alzheimer's disease received vinpocetine (30, 45 or 60mg/day) or a placebo for one year. Several cognitive tests were performed during and after the study. No difference was found between the placebo and vinpocetine groups. No significant side effects were observed from the vinpocetine.
Most beneficial for - Both healthy individuals and those with cognitive problems have demonstrated benefit
Effective dose - 10-60mg daily has shown to be effective
Length of action - Studies indicate that its benefits begin after 2 days and continue with use at least to 16 weeks
Safety - No adverse effect were reported in these studies at the effective doses
Type cognition effected - Memory (including short term memory),
Enhancers - possibly Ginkgo Biloba
Supporting Human Studies
Psychopharmacological effects of vinpocetine in normal healthy volunteers (Subhan et al, 1985)
Twelve healthy female volunteers received vinpocetine (10, 20, 40mg/day) or a placebo over 3 days before performing a battery of psychological and cognitive tests. The 40mg dose of vinpocetine was shown to improve scores on the memory test significantly compared to the placebo group. All other tests (critical flicker fusion, choice reaction time and rating of drug effects) showed no differences between groups.
Possible memory-enhancing properties of vinpocetine (Coleston et al, 2004)
Twelve volunteers received vinpocetine (40mg) or a placebo for two days. They then underwent several cognitive tests. Results showed a significant improvement in short term memory in the vinpocetine group compared to the placebo.
Investigation of the effect of vinpocetine on cerebral blood flow and cognitive functions (Valikovics et al, 2007)
Two groups of patients with mild cognitive impairment or ischemic stroke had cerebral blood flow and cognitive function measured before and after the administration of vinpocetine. The patients took vinpocetine for 12 weeks. At the end of the 12 week cycle cerebral blood flow was significantly increased as was performance on cognitive tests. This was identical in both groups of patients.
Efficacy and tolerance of vinpocetine in ambulant patients suffering from mild to moderate organic psychosyndromes (Hindmarch et al, 1991)
Elderly patients (N=165) with mild to moderate psychosyndromes received vinpocetine (30 or 60mg) or a placebo daily for 16 weeks. Cognitive and mood was evaluated after 16 weeks. The vinpocetine was shown to significantly improve several mood and cognitive factors compared to the placebo. No adverse drug reactions were observed in the vinpocetine group either.
Vinpocetine Effects on Cognitive Impairments Produced by Flunitrazepam (Bhatti et al, 1987)
The effects of pre-treatment with vinpocetine 40 mg, on flunitrazepam-induced impairment of memory, were studied in 8 normal volunteers. Tests of Critical Flicker Fusion Threshold, a Sternberg Memory Scanning Task, along with subjective ratings of drug action were used. Drug effects were found to be modest. Treatment with vinpocetine was associated with improvements in short-term memory processes.
Clinical evidence of the effectiveness of vinpocetine in the treatment of organic psychosyndrome (Blaha et al, 1989)
In this double blind placebo controlled trial 282 patients with mild to moderate psychosyndromes caused by cerebral blood supply disorders randomly received vinpocetine (5, 10 and 20mg) three times per day or a placebo.
Those taking the vinpocetine showed significant improvements in clinical global impression and performance SKT tests compared to the placebo group. Higher doses of vinpocetine showed greater effects.
A double-blind placebo controlled evaluation of the safety and efficacy of vinpocetine in the treatment of patients with chronic vascular senile cerebral dysfunction (Balesteri et al, 1987)
In a double-blind clinical trial vinpocetine was shown to effect significant improvement in 84 57–94 yr old patients with chronic cerebral dysfunction. 42 patients received 10 mg vinpocetine 3 times a day for 30 days, then 5 mg three time a day for 60 days. Matching placebo tablets were given to another 42 patients for the 90-day trial period. Patients taking vinpocetine scored consistently better in all evaluations of the effectiveness of treatment including measurements on the Clinical Global Impression Scale, the Clinical Assessment-Geriatric Scale, and the Mini-Mental Status Questionnaire. No serious side effects were noted.
Vinpocetine increases cerebral blood flow and oxygenation in stroke patients: a near infrared spectroscopy and transcranial Doppler study (Bonoczk et al, 2002)
Forty three patients suffering stroke were randomized to receive either 20mg of vinpocetine intravenously or a placebo. Blood flow and oxygenation were measured in the brain before and after undergoing the treatment. Results of the tests showed that vinpocetine significantly increased both the level of blood flowing into the brain as well as its oxygenation of brain tissue compared to the placebo group.
Supporting Animal Studies
Vinpocetine: Nootropic effects on scopolamine-induced and hypoxia-induced retrieval deficits of a step-through passive avoidance response in rats (DeNoble et al, 1985)
Cognitive impairments were induced in rats using either drugs or hypoxic conditions. Vinpocetine was then administered at varying doses and the effects on cognitive tests observed. Vinpocetine at the peak dose of 20mg/kg prevented drug induced memory deficits. Vinpocetine at 3mg/kg also prevented disruption of passive avoidance retention impaired by hypoxic conditions.
The impairment of long-term potentiation in rats with medial septal lesion and its restoration by cognition enhancers (Molnar et al, 1994)
Rats had their brains lesioned and then underwent test to observe its effect on long term memory formation. The lesion did demonstrate significant reductions in long term memory parameters. Some rats received vinpocetine 1 hour after lesion formation and daily for 6 days thereafter. Vinpocetine completely restored the negative effects caused by the lesion.
Vinpocetine enhances retrieval of a step-through passive avoidance response in rats (DeNoble, 1987)
Rats were studies for the effects of vinpocetine on a passive avoidance task. Vinpocetine administered 60 minutes before testing significantly increased the rats performing the passive avoidance. The range of effective doses was 18-30mg/kg.
Amelioration of intracerebroventricular streptozotocin induced cognitive dysfunction and oxidative stress by vinpocetine — a PDE1 inhibitor (Deshmukh et al, 2009)
Rats were given a drug to induce cognitive decline similar to that in Alzheimer's disease. They then received vinpocetine (5, 10 and 20mg/kg/day) for 21 days. All doses of vinpocetine were found to improve learning and memory in water mazes and passive avoidance tests. Also observed were reductions in oxidative stress as well as improvement in cholinergic function.
Cellular Studies
Idebenone and vinpocetine augment long-term potentiation in hippocampal slices in the guinea pig (Ishihara et al, 1989)
Hippocampal segments of guinea pig brain were cultured with or without vinpocetine. Results showed that the addition of vinpocetine significantly augmented long term potentiation in the hippocampal segments.
Contradictory Studies
None
Combinational Studies
Cognitive effects of a Ginkgo biloba/vinpocetine compound in normal adults: systematic assessment of perception, attention and memory (Polich et al, 2001)
A battery of computerized tests was performed by 24 healthy adults. Half the adults received a ginkgo biloba/vinpocetine supplement and the other half a placebo for 14 days prior to the tests. Those receiving the ginkgo/vinpocetine supplement demonstrated a 50ms response improvement on a test for short term working memory.
Safety Studies
The safety and lack of efficacy of vinpocetine in Alzheimer's disease (Thal et al, 1989)
Fifteen patients with Alzheimer's disease received vinpocetine (30, 45 or 60mg/day) or a placebo for one year. Several cognitive tests were performed during and after the study. No difference was found between the placebo and vinpocetine groups. No significant side effects were observed from the vinpocetine.