Alzheimer’s disease is perhaps one of the most dreaded diseases of old age. While research has made great strides in the realm of prevention—uncovering several brain-supportive nutritional supplements that help protect against cognitive deterioration—significantly less progress has been achieved in the way of long-term treatment or cure.
But, thankfully, that is slowly changing. And yet again, research proves that nature provides the best potential medicine for even the worst of diseases.
In a recently published study, a team of researchers examined the leaves of a tropical tree known as “neem” (Azadirachta indica) for its effects on Alzheimer’s disease.1 Native to India, Sri Lanka and neighboring countries with similar tropical climates, the neem tree serves multiple functions—in fact, almost every part has some special use.
The tree’s fruit is edible; its wood can be used to make furniture; the leaves and bark have been used in teas, cosmetics and medicinal preparations; twigs can be made into toothbrushes; and neem oil has insecticidal and fungicidal properties.
Because previous studies have also shown that the neem tree possesses anti-anxiety, anti-inflammatory and cognition-enhancing attributes,2-4 researchers in the current study wanted to see if neem had any influence on Alzheimer’s disease.
This study used rats that had artificially induced Alzheimer’s disease, minus a group of “sham” controls that did not have any brain alterations, nor did they receive any treatment during the course of the experiment other than placebos.
Prior to Alzheimer’s induction, select rats received seven days of pretreatment with A. indica, while the remaining did not. The rats were then randomly divided into several groups to undergo various cognitive and neurobehavioral tests, including:
- The open field test, which checked for locomotor activity and exploratory behavior.
- The elevated plus maze behavior test, which analyzed anxiety levels. (Higher anxiety levels lead to decreased mobility, with animals preferring to stay in darkness versus open areas that allow for movement and exploration.)
- The forced swim test, which checked for depressant/antidepressant activity. In this test, researchers observed the rats’ period of immobility in a contained cylinder filled with water to note how long they remained floating without struggling, making only the necessary movements to keep their heads above water.
- The Morris’ water maze test, which evaluated spatial learning, reference memory and working memory.
- Conditioned avoidance behavior testing, during which researchers looked for active avoidance learning, acquisition and retention.
After the experimental period, the rats were sacrificed under anesthesia and their forebrains collected for analysis.
The researchers found that for all tests conducted, the rats pretreated with A. indica performed better than the controls.
For instance, in the open field test, the pretreated rats had increased numbers of movements. In the elevated plus maze test, researchers noted that the non-treated rats spent more time in isolation, while the rats pretreated with A. indica did not.
In the forced swim test, the A. indica pretreatment reduced immobility compared to control animals, suggesting antidepressant activity. The Morris’ maze test showed that reference memory and spatial learning improved in all groups, which researchers noted “confirms the memory-enhancing effect of this herbal drug.”
Finally, in the conditioned avoidance paradigm, A. indica-pretreated rats displayed better learning and retention of learned behavior.
The researchers concluded, “It is well evident that…A. indica is effective in reversing the neurobehavioral changes, attenuating the cognitive deficits and decreasing the oxidative stress in experimental [Alzheimer’s disease] models.”
Of course, being a preliminary study, further research on humans must be conducted to verify these results—but they definitely look promising.
Any patient with Alzheimer’s hopes for as much time as possible to live a normal, independent life—and if something as simple and natural as a tree/plant extract can provide that, it’s undoubtedly worth further experimentation.
If you or someone you love currently deals with cognitive decline or Alzheimer’s disease, it doesn’t hurt to start supplementing now with neem leaf products, many of which can easily be found at health food stores and online.
- Raghavendra M, et al. Int J Appl Basic Med Res. 2013 Jan-Jun;3(1):37-47.
- Jaiswal AK, et al. Indian J Exp Biol. 1994 Jul;32(7):489-91.
- Chattopadhyay RR. Indian J Exp Biol. 1998 Apr;36(4):418-20.
- Verma S, et al. Indian J Pharmacol. 1989;21:46-50.