Industrial hemp (C.sativa) has a low content of the THC, less than 0.3% when the dry, as a legal limit for cultivation. Hemp seed is derived from the pollinated plant.
Hemp seed has been used in human nutrition in the form of the oil, milled seed, and as a source of vegetable protein and dietary fiber. It’s filled with important nutrients, especially unsaturated fatty acids, and essential amino acids that are in the correct ratio for human dietary demands.
There are other positive effects from the hemp seed, such as cardiovascular benefit, relief from indigestion, and treatment of dermatological diseases. Hemp seed extract also shows anti-mutagenic properties and anti-aging effects. It can improve chemical drug-induced impairment for learning and memory. Hemp seed is also rich in other compounds, the most abundant of these being phenyl propionamide (TPA). Fourteen of these compounds have been isolated and extracted for the study described below.
Neuroinflammation is the hallmark of Alzheimer’s disease, and other neurodegenerative conditions. Mice, with induced systemic and central inflammatory responses that mimic the neuroinflammation in humans, were used for this research.
Hemp was dried and crushed to extract the TPA. The quantification was performed by the HPLC method, which identifies exact compounds based on their UV spectral characteristics. There were 60 mice used, divided into 5 random groups, including: control, model, TPA and piracetam.
Piracetam is used as a positive control, due to its therapeutic effects on aging and cognition, and its ability to improve the mitochondrial function that ultimately affects brain activity.
All of the mice were injected with lipopolysaccharide (LPS) to mimic neuroinflammation in humans. This treatment increases the neuroinflammatory markers in brain called: IL-1β, IL-6 and TNFα. The levels of these markers are easily measured by enzyme-linked immunosorbent assay (ELISA).
The results showed that low doses of TPA significantly reduced the expression of the IL-1β, IL-6 and TNFα in the brains of the LPS-induced mice. After looking at the neurons in the hippocampus area, it was found that the TPA prevented damage of these hippocampal neurons.
An interesting result was around dosing of TPA -more is not necessarily better. The most effective dose was less than 2g/kg, because 1g/kg indicated better neuroprotection than the 2g/kg. Either way the dosing should be studied in more detail so that patients can be informed on what volume of seeds they need to eat to reduce inflammation in the brain.
Also, the results showed that TPA significantly improved learning and memory of the LPS-induced neuroinflammatory mice and improved their cognitive function – according to the behavioral tests performed with these mice.
According to the literature reports, 20 types of the TPA have been isolated from hemp seed. Some of these demonstrated great antioxidant and anti-neuroinflammatory properties. Bioactivity and health benefits must be considered when identifying a functional food.
Even though the study clearly defines the benefits of the TPA on the neuroinflammation in mice, it is important to remember that sometimes it is difficult to translate this to humans. The reason is mostly difference in physiology, dosing etc. Additionally, most of these results of this study were shown post-mortem, which is impossible with the human patients. Still, hemp seeds are good for you no matter what, and may be part of a future treatment plans for Alzheimer’s and other neuro-inflammatory conditions.