Rosmarinus Officinalis (Rosemary)
Rosmarinus officinalis or Rosemary as it is more commonly known is a small shrub that comes for the mediterranean region. It is mostly known as a herb for flavoring meat dishes from this region. Interestingly in ancient times it was known as a herb of memory and used to improve and enhance it.
Current studies of rosemary do indicate some enhancement of cognitive function however studies in humans are limited and there may be several modes of action. The only study conducted on humans was exploring the fragrance of rosemary essential oil on cognitive performance. It would appear that the smell of rosemary improves both memory and alertness but this effect is probably different to effects caused by ingestion of rosemary. To understand rosemary we have to break it down into its active molecules. So far molecules in rosemary with potential cognitive enhancing abilities are rosmarinic acid and carnosic acid. So far in both animal and cellular studies these components have been shown to increase nerve growth and differentiation, increase acetylcholine levels and improve overall cognition and memory. Rosemary looks very promising as a cognitive enhancer but for the time being needs more research to determine human effects and dosages.
Most beneficial for - Anyone wanting to improve memory and attention
Effective dose - essential oil fragrance is enough, unknown for internal consumption
Length of action - unknown
Safety - has a long history of safe use (not known for cognitive enhancing doses)
Type of cognition effected - general memory and attention
Enhancer - unknown
Aromas of rosemary and lavender essential oils differentially affect cognition and mood in healthy adults (Moss et al, 2003)
Participants completed a battery of cognitive test in a room with rosemary essential oil fragrance, lavender essential oil fragrance or no fragrance. The rosemary fragrance produced and overall enhancement in memory and second memory factors but also slowed speed of memory compared to control subjects. Rosemary fragrance significantly increased alertness compared to both other groups.
Effect of Rosmarinic Acid on Aged Mice in Morris Water Maze Performance (Zhou et al, 2009)
Mice with a cognitive deficit were treated with rosmarinic acid at doses of 100mg/kg and 200mg/kg for 5 days. Test results showed that the mice that received rosmarinic acid performed better in memory tests than did the control group.
Subchronic administration of rosmarinic acid, a natural prolyl oligopeptidase inhibitor, enhances cognitive performances (Park et al, 2010)
Rosmarinic acid was given to rats and its effect measured over short, medium and long term. Both the short and medium term testing showed significant improvements in solving a maze at specific dosage ranges. Long term administration significantly improve performance in the maze over and above the short and medium term. Rosmarinic acid was also shown to inhibit propyl oligopeptidase which is known to improve memory.
Effects of Rosmarinus Officinalis L. aerial parts essential oil on intact memory and scopolamine-induced learning deficits in rats performing the morris water maze task (Hosseinzadeh et al, 2004)
Rats were injected with rosmarinus oil 30 minutes before performing the water maze. The oil at doses of 125-250mg/kg decreased the time it took rats to solve the maze. It also reduced the effect of scopolamine on memory.
Carnosic Acid, a Component of Rosemary (Rosmarinus officinalis L.), Promotes Synthesis of Nerve Growth Factor in T98G Human Glioblastoma Cells (Kosaka and Yokoi, 2003)
Human braincells were exposed to a rosemary extract containing carnosic acid and carnosol. This extract was shown to increase the production of Nerve Growth factor. Nerve growth factor is important for growth and functioning of nerve tissue.
Role of Nrf2 and p62/ZIP in the neurite outgrowth by carnosic acid in PC12h cells (Kosaka et al, 2010)
Carnosic acid was administered to neurons in a laboratory setting. Carnosic acid was shown to stimulated neurite outgrowth (growth of neuron structures that form connections) and differentiation (aqusition of specialised functions by nerve cells). The pathways by which it does this were identified as Nrf2 and p62/ZIP.
Rosmarinic acid from Perillae Herba produces an antidepressant-like effect in mice through cell proliferation in the hippocampus (Ito et al 2008)
Mice were given rosmarinic acid for 7 or 14 days and then there brains studied for neuron growth. Significant proliferation of neurons was found in the hippocampus of mice given rosmarinic acid.
Rosmarinus officinalis polyphenols activate cholinergic activities in PC12 cells through phosphorylation of ERK1/2 (Abdelfatteh et al, 2010)
Rat Neural cells were exposed to rosemary polyphenols. It was observed that two compounds in particular rosmarinic acid and carnosic acid significantly induced cell differentiation, increased acetylcholine levels and enhanced acetylcholinesterase activity.
Inhibitory effect of Turkish Rosmarinus officinalis L. on acetylcholinesterase and butyrylcholinesterase enzymes (Orhan et al, 2007)
This study tested the ability of various rosemary extracts to inhibit acetylcholinesterase in test tubes. Several molecules found in rosemary including rosmarinic acid had significant acetylcholinesterase inhibitory effects.
Current studies of rosemary do indicate some enhancement of cognitive function however studies in humans are limited and there may be several modes of action. The only study conducted on humans was exploring the fragrance of rosemary essential oil on cognitive performance. It would appear that the smell of rosemary improves both memory and alertness but this effect is probably different to effects caused by ingestion of rosemary. To understand rosemary we have to break it down into its active molecules. So far molecules in rosemary with potential cognitive enhancing abilities are rosmarinic acid and carnosic acid. So far in both animal and cellular studies these components have been shown to increase nerve growth and differentiation, increase acetylcholine levels and improve overall cognition and memory. Rosemary looks very promising as a cognitive enhancer but for the time being needs more research to determine human effects and dosages.
Most beneficial for - Anyone wanting to improve memory and attention
Effective dose - essential oil fragrance is enough, unknown for internal consumption
Length of action - unknown
Safety - has a long history of safe use (not known for cognitive enhancing doses)
Type of cognition effected - general memory and attention
Enhancer - unknown
Aromas of rosemary and lavender essential oils differentially affect cognition and mood in healthy adults (Moss et al, 2003)
Participants completed a battery of cognitive test in a room with rosemary essential oil fragrance, lavender essential oil fragrance or no fragrance. The rosemary fragrance produced and overall enhancement in memory and second memory factors but also slowed speed of memory compared to control subjects. Rosemary fragrance significantly increased alertness compared to both other groups.
Effect of Rosmarinic Acid on Aged Mice in Morris Water Maze Performance (Zhou et al, 2009)
Mice with a cognitive deficit were treated with rosmarinic acid at doses of 100mg/kg and 200mg/kg for 5 days. Test results showed that the mice that received rosmarinic acid performed better in memory tests than did the control group.
Subchronic administration of rosmarinic acid, a natural prolyl oligopeptidase inhibitor, enhances cognitive performances (Park et al, 2010)
Rosmarinic acid was given to rats and its effect measured over short, medium and long term. Both the short and medium term testing showed significant improvements in solving a maze at specific dosage ranges. Long term administration significantly improve performance in the maze over and above the short and medium term. Rosmarinic acid was also shown to inhibit propyl oligopeptidase which is known to improve memory.
Effects of Rosmarinus Officinalis L. aerial parts essential oil on intact memory and scopolamine-induced learning deficits in rats performing the morris water maze task (Hosseinzadeh et al, 2004)
Rats were injected with rosmarinus oil 30 minutes before performing the water maze. The oil at doses of 125-250mg/kg decreased the time it took rats to solve the maze. It also reduced the effect of scopolamine on memory.
Carnosic Acid, a Component of Rosemary (Rosmarinus officinalis L.), Promotes Synthesis of Nerve Growth Factor in T98G Human Glioblastoma Cells (Kosaka and Yokoi, 2003)
Human braincells were exposed to a rosemary extract containing carnosic acid and carnosol. This extract was shown to increase the production of Nerve Growth factor. Nerve growth factor is important for growth and functioning of nerve tissue.
Role of Nrf2 and p62/ZIP in the neurite outgrowth by carnosic acid in PC12h cells (Kosaka et al, 2010)
Carnosic acid was administered to neurons in a laboratory setting. Carnosic acid was shown to stimulated neurite outgrowth (growth of neuron structures that form connections) and differentiation (aqusition of specialised functions by nerve cells). The pathways by which it does this were identified as Nrf2 and p62/ZIP.
Rosmarinic acid from Perillae Herba produces an antidepressant-like effect in mice through cell proliferation in the hippocampus (Ito et al 2008)
Mice were given rosmarinic acid for 7 or 14 days and then there brains studied for neuron growth. Significant proliferation of neurons was found in the hippocampus of mice given rosmarinic acid.
Rosmarinus officinalis polyphenols activate cholinergic activities in PC12 cells through phosphorylation of ERK1/2 (Abdelfatteh et al, 2010)
Rat Neural cells were exposed to rosemary polyphenols. It was observed that two compounds in particular rosmarinic acid and carnosic acid significantly induced cell differentiation, increased acetylcholine levels and enhanced acetylcholinesterase activity.
Inhibitory effect of Turkish Rosmarinus officinalis L. on acetylcholinesterase and butyrylcholinesterase enzymes (Orhan et al, 2007)
This study tested the ability of various rosemary extracts to inhibit acetylcholinesterase in test tubes. Several molecules found in rosemary including rosmarinic acid had significant acetylcholinesterase inhibitory effects.