I have been interested a lot recently in restoration of the nervous system with natural methods. Nerve related diseases range from painful conditions such as various types of neuropathy to cognitive disorders, like Alzhemers and dementia. These conditions fall under the umbrella of ‘nerve damage’. I will now describe my top 5 regenerative herbs for the nervous system in more detail referring to both traditional and scientific knowledge.
Ashwagandha is classified as a rasayana herb in Ayurvedic medicine, this means it has rejuvenating qualities that increase life-span, improve overall health, and fight disease (Ven Murthy et al., 2010). Ashwagandha is considering an adaptogen, a term that refers to a nontoxic medication that normalises various functions perturbed by body stress. It is hypothesised to do this by correction of imbalances in the neuroendocrine and immune system. The winanosides are thought to be the primary active compounds of ashwagandha and are found in the root. Alzheimer’s disease is hypothesised to be caused by deposition of amyloid β-peptide in plaques in human brain tissue (Hardy et al., 2002). In one notable study, the authors found that an ashwagandha root extract was capable of reversing amyloid induced toxicity in human neuronal cells (Kurapati et al., 2013), therefore supporting the potential for this herb to be a treatment for Alzheimer’s. Ashwagandha also has anti-oxidant properties (Bhattacharya et al., 2001), and oxidative stress is associated with neurodegeneration (Federico et al., 2012). Another interesting study, in an animal model, found a withanoside from ashwagandha increased regeneration of a damaged nerves after injury (Nakayama et al., 2007). In summary, these studies point to the value of ashwagandha in restoring the health of the nervous system.
2. Gotu kola
Gotu kola, similar to ashwagandha, is classified as a rasayana herb in Ayurveda. Originally it was used by local people in Sri Lanka as a tonic herb for longevity (Castleman, 2001). It was incorporated into both traditional Indian and Chinese medicine for longevity and to treat cognitive problems. Impaired anti-oxidant mechanisms have been implicated in Alzheimer’s disease (Markesbery, 1997). More recently, in animal models, it has shown to have anti-oxidant activities in the brain and to exert a protective effect against cognitive problems (Kumar et al., 2003). Another study found both in cellular ex vivo and in vivo animal models that gotu kola facilitated axon regrowth and remyelination after damage (Soumyanath et al., 2005). Although these were animal or cellular studies they point to the medicinal potential of gotu kola to restore a damaged nervous system alongside the traditional application of the herb.
Ginkgo is a giant tree which grows up to 125-foot-tall and lives up to 1000 years (Castleman, 2001). It is a relic of a lost era and has survived since the Jurassic period, when the dinosaurs ruled the world, 170 million years ago (Zhou et al., 2003). Ginkgo otherwise known as the maidenhair tree has changed very little morphologically over 170 million years. It has long been used in Chinese and Indian traditional medicine and Ayuvedic physicians viewed it as a tonic for longevity (Castleman, 2001). Ginkgo is another anti-oxidant herb (Bridi et al., 2001). It has convincing support in human studies to reduce the severity of Alzheimer’s disease and dementia (Le Bars et al., 1997). A study using experimental models, found that ginkgo extracts enhanced axonal extension in Schwann cells and promoted peripheral nerve functional recovery (Hsu et al., 2004). Like ashwagandha and gotu kola, ginkgo is another herb with great potential to restore the nervous system.
Bacopa is classified as a ‘medhya rasayana’ in Ayurveda, a rasayana medicine specifically for the mind and nervous system (Russo et al., 2005). Bacopa can be found in the Caraka Samhita a text from the 6th century A.D. In this key text, it is recommended to treat cognitive problems. Bacopa has been found to have anti-oxidant activities in the rat brain (Bhattacharya et al., 2000). Well conducted human clinical studies support Bacopa as having cognitive boosting effects (Roodenrys et al., 2002). Bacopa has been shown to inhibit acrylamide (a toxic chemical) induced neuropathy in drosophila likely via raising anti-oxidant levels (Kunnel et al., 2013). Another study found that an extract of bacopa could reduce neuropathic pain in rats (Sahoo et al., 2010). These studies underscore the potential for bacopa to heal damaged nerves and support its traditional role as a ‘medhya rasayana’.
5. St. John’s wort
St. John’s wort’s importance in herbalism can be traced back to the ancient Greeks (Castleman, 2001). The famous Greek physician Dioscorides recommended it for sciatica, a nerve related problem. St. John’s wort has anti-oxidant abilities (Zou et al., 2004), which may be related to its health promoting effects on the nervous system. A well conducted human study on neuropathy found, although the effects were not quite statistically significant, that it seemed to reduce pain with patients suffering from polyneuropathy (Sindrup et al., 2001). This implies that if repeated with a higher patient number and a higher dosage the effects would be more noticeable. In another study using animal models, it was found that St. John’s wort reduced neuropathic pain (Galeotti et al., 2010), thus supporting the traditional use of the herb and the human study in 2001. St. John’s wort also has anti-depressant activity and these classes of medicines are linked to reducing neuropathic pain (Saarto et al., 2007). Overall, St. John’s wort appears to be a potent tonic for the nervous system and worthy of much further study.
Ashwagandha, bacopa, gotu kola, ginkgo, and St. John’s wort are some of the most potent tonics for the nervous system we have in herbalism. David Winston has used St. John’s wort with bacopa, ginkgo, and holy basil for brain injury with remarkable success (Groves, 2016). In treating complex difficult nerve related conditions a combination formula seems best. For more detail on constructing a formula, I would refer you to an excellent book by Maria Groves called ‘Body into Balance’. Also, each of these herbs has a specific entry in my herbal encyclopedia.
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