Fi speaks with Arjan Scheepens, PhD, neuroscientist at HortResearch in New Zealand. Dr Scheepens is measuring specific psycho- and bio-active effects of plant-based materials with a view to designing natural nutraceuticals to relieve symptoms of stress, mental fatigue, hypertension and the cognitive decline associated with ageing, using New Zealand-based agricultural products.
FI: The concept of "mood food" relies on an understanding of how we can affect our mood with combinations of food. Phospholipids or fatty acids are popular here (the brain is mostly comprised of fat, after all), as are various botanicals. What is it in the fruits — New Zealand fruits at that — that are to account for the benefit?
AS: It is not likely to be one compound, but a combination of things. There are actually a lot of phytochemicals that are know to have strong effects on mood but most are either not absorbed at all, poorly absorbed or altered during digestion into inactive metabolites. There's also the problem of the blood-brain barrier, which makes it very hard to get most compounds into the brain at effective concentrations.
Our focus is on designing intelligent synegies between compounds that aid in absorption and increasing bioavailability and access through the blood-brain barrier. There are also several targets outside the brain that can be targeted more easily with ingested functional foods to alleviate some of the symptoms of stress and anxiety, like adrenergic antagonists (beta-blockers) or ACE inhibitors, classicaly used to treat hypertension. We are lucky in New Zealand and especially within HortResearch to have access to a huge number of fresh tropical and sub tropical fruits as well as the more common fruits like pipfruit and stonefruit.
FI: What is the mechanism of action — serotonin, neurotransmitters, receptors?
AS: It really depends on the target — our primary targets are anxiety, depression and the cognitive decline associated with normal ageing. Preferably we would target systems outside the brain as these are a more realistic target for consumed foods. As with most nutraceuticals, it is better to target many systems at sub-pharmacological doses than to target a single system pharmacologically. This also lessens the possiblity of side effects or the possibility for abuse.
With anxiety, for example, we would typically be interested in phytochemicals that increase GABA function or which are directly GABAergic as well as monoamine oxidase inhibitors (MAOI's). We would also look at synergies to protect bioactive phytochemicals from metabolic degradation or enhance their absorption; for example, the MAOI's can also protect active plant-derived mono amines from being degraded. Some of our more edgy science is in the search of plant-derived corticotropin-releasing hormone receptor 1 antagonists (CRH-R1), which is a very hot topic in current clinical pharmacology. Classical targets like acetylcholinesterase inhibitors for slowing cognitive decline are also under consideration.
FI: Is any of this based on advanced technology delivery systems, such as nanotechnology or breeding practices? Or is it just a specific combination of fruit juices?
AS: Bioactive molecules, or more likely sets of synergistic bioactives that we discover in the mood food programme, are fed directly back into our plant breeding teams here at HortResearch, who then use selective breeding techniques to enhance the levels or distribution of these in a particular fruit — creating superfruits with defined functionality without the use of genetic engineering. We also have a wealth of experience in plant genetics that allows us to judge the seedlings for suitability using genetic screens well before they are ready to fruit, which would normally take several years. This way we do not have to wait for a seedling to fruit, but can test whether it has enhanced capability when it is only a few months old. This gives us an enormous time and cost advantage over traditional plant breeding methods.
Also, if specific bioactives have a particularly bad taste or poor solubility, then we will consider micro-encapsulation in phospholipids, in which we also have considerable experience.
FI: Is there any element of applied research — that is, into specific applications for the food, beverage or supplements industries?
AS: While we do basic research, it is not just research for research's sake — it is done with products and markets in mind. What we want is for the fruits of our research to end up in a consumer product. We are also involved in clinical trials and our point of difference with most nutraceuticals and dietary supplements is that we will have hard science and well designed clinical trials to prove efficacy before anything is released to consumers. We take this very seriously and have invested substantial amounts of our own money and time into this programme. The last thing the consumer needs is more so called functional foods with only in vitro evidence, or worse, no hard evidence for efficacy whatsoever.
FI: Because the juice combination appears to have the opposite effect as caffeine — it relaxes instead of makes jittery — is there any thought to combining it with caffeine to give the "alert" benefits of caffeine without the "jittery" downside?
AS: The caffeine market is oversaturated with products and is not a target of our work. The current clinical trial is in regards to a product that may decrease the negative effects of stress as well as increase cerebral blood flow and thus possibly improve cognition and executive functioning, especially whilst under stress, which is an enormous problem in today's workplace.
FI: Who is the market for such fruit beverages?
AS: Everyone who gets stressed — our intial target market is:
- Above average household income
- At least one child living at home
- Tertiary educated
We chose this because our preliminary research indicated that these women are experiencing high levels of stress trying to balance careers and family, and in general women are more likely to do something about their stress than men.
The World Health Organisation predicts that depression will be the second highest cause of death and disability worldwide by 2020, and numerous surveys put stress near the top of consumers health concerns. For example, the respected HealthFocus survey of Spanish consumers ranks stress as number 4 when asked what conditions personally affected consumers.