Parallel with the growing body of Western research, over the past decade Chinese and other (mostly Asian) researchers have also been investigating the human microbiota and correlating their findings with TCM theory as well as the traditional actions of the Chinese herbal materia medica (CHM). Such studies are becoming increasingly common and it is not unusual for new information to become available on a monthly basis. In the time between completing my research for Part 2 of this series, and commencing research for this article, several relevant papers have been published dealing with the actions of herbal components and herbal formulas in relation to the intestinal barrier and the microbiota.
We should, however, be careful when evaluating the effects of herbs, formulas or herbal components in this way. Firstly, many of the studies have been carried out using animal models, and, secondly, only a very limited number of herbs and formulas have been studied to date. Therefore when a herb or formula is mentioned in the summary that appears below, the information should be understood within this context, and there may well be other herbs and formulas that are just as effective as the ones mentioned, but they have not as yet been formally studied.
Studies on TCM Herbs and Formulas
A recent review paper summarises the current thinking on the correlations between TCM theories and the state of the intestinal barrier and the microbiota:
(TCM internal organ) ‘theory emphasizes functional integration rather than the individual anatomical organs…. (the Spleen-Stomach) are mainly involved in digestion, as well as immunity, hematopoiesis, and metabolism, which is functionally consistent with the roles of the gut microbiota’. (italics, mine) (1) Therefore, it is not surprising that much of the CHM-microbiota-gut-barrier-function research has been carried out in relation to herbs and formulas that act on the Spleen, e.g. by tonifying, resolving various types of Damp (e.g. turbid Damp, Phlegm-Damp or Damp-Heat), warming, regulating and moving the Qi.
In terms of structural and functional components within the gut, the targets of herb action, together with the herbs and formulas that have been studied in connection with them, may be summarised as follows (2 – 18):
- INTESTINAL SMOOTH MUSCLE – to promote motility.
Citrus, Cyperus, Lindera, Atractylodes lancea, Li Zhong Wan.
- LOCAL IMMUNE SYSTEM – adaptogenic and anti-inflammation actions.
Astragalus, Codonopsis, Panax, Angelica Dang-gui, Atractylodes, Yu Ping Feng San, Ping Wei San.
- EPITHELIUM – assist regeneration.
Astragalus, Angelica Dang-gui, Licorice, berberine (component of Coptis and Scutellaria), Si Ni San, Huo Xiang Zheng Qi San
- destroy or inhibit pathogens: Coptis, Scutellaria, Agastache, Perilla, Rheum, Forsythia, Lonicera.
- promote probiotic species: Astragalus, Codonopsis, Panax, Atractylodes, Rehmannia, Glycyrrhiza, Lonicera.
The above represents only the ‘tip of the iceberg’, as research in this area has only begun quite recently. As more results come to light, we will no doubt be able to use existing herbal formulas or design new ones specifically targeted towards treating dysbiosis and repairing the gut barrier. It is interesting to note that much of the currently available information, summarised above, confirms the clinical applications of herbs and formulas as they have been used in TCM during the past two millennia.
TCM Syndrome-Patterns and Western Biomedical Pathologies
Although there is no clear-cut one-on-one correlation between the various TCM Spleen disorders and the pathological changes that are associated with dysbiosis, impaired intestinal barrier function and intestinal inflammation, the two paradigms do, in fact, have several significant points of intersection.
Mild or transient dysbiosis is not as yet tied to any specific biomedically defined disease and is generally recognised to occur in association with antibiotic use, as described in the subsequent paragraph. Although a causal relationship has not yet been established, there is growing evidence of a very close association between dysbiosis, with impaired intestinal barrier function, and various pathological conditions, both within and outside of the intestines. Intestinal disorders include inflammatory bowel disease, irritable bowel syndrome and coeliac disease; while extra-intestinal disorders include allergy, asthma, metabolic syndrome, cardiovascular disease, and obesity. In addition, studies on germ-free mouse models indicate that disruption of the intestinal microbiota plays an important role in the pathogenesis of various auto-immune diseases, such as arthritis, systemic lupus erythematosus, type 1 diabetes, and encephalomyelitis. (19)
Staying with intestinal disorders, the common symptoms associated with dysbiosis and impaired intestinal barrier function include the following: fatigue, fever, bloating, loss of appetite, abdominal discomfort or pain, loose stools or diarrhea, and nausea. These symptoms may be seen in cases with antibiotic associated diarrhea. (20, 21) In more severe conditions, where the dysbiosis and impaired barrier function are accompanied by chronic inflammation, such as Crohn’s disease and ulcerative colitis, symptoms may also include: severe cramping abdominal pain, mucous or blood in the stools, rectal bleeding, urgency and tenesmus. (22) These core symptoms are consistent with the following patterns of Spleen imbalance (23, 24):
- Spleen deficiency
- Defense Qi deficiency
- Cold-Damp obstruction
- Qi stagnation in the Stomach and Intestines
- Damp-Heat (retained in the Stomach and Intestines)
- Damp stagnation in the Liver and Gallbladder, Liver-Spleen disharmony
Putting the above information together, we can make the following correlations:
- The microbiota may be regarded as an important component of the Spleen Qi. A healthy state of the microbiota will be present when the Spleen is functioning normally; and normal Spleen function equates with a healthy intestinal microbiota population.
- A state of dysbiosis correlates with various pathological states of the Spleen, i.e. Spleen Qi deficiency, retention of Cold-Damp or Damp-Heat, and stagnation of the Qi in the Stomach and Intestines.
- Barrier function (both intestinal and respiratory) is part of the defense Qi (wei qi), which, in turn, is a product of the Yang functions of both Spleen and Kidney. Thus, when the defense Qi is weakened, the Spleen Yang and Kidney Yang are generally also involved.
- Disturbances in the motility of the GIT may be correlated with the pattern of Qi stagnation; and in cases where the symptoms arise or worsen when there is emotional strain of stress, with Liver constraint and the Liver Qi invading the Spleen.
- Inadequate bile formation and secretion, leading to bacterial overgrowth in the small intestines may be correlated with Damp stagnation in the Liver and Gallbladder, with Liver-Spleen disharmony.
- In terms of the approach to treatment, removal of pathogens should take precedence in the early stages of treatment (corresponding to the ‘weed’ phase), and tonification is required in the later stages of treatment (corresponding to the ‘feed’ phase). This should be applied in a flexible way, according to the needs of each individual patient. Generally, TCM herbal therapy applies both approaches at once, giving one precedence over the other at different stages.
Clinical Protocols For Gut Healing
Spleen Qi deficiency
Key clinical features: fatigue, poor appetite, feeling full after eating very little, loose stools, pale tongue and a weak pulse.
Treatment formula: Bu Zhong Yi Qi Tang
(available as: Energy Tonic Formula, or Ginseng & Astragalus Formula)
- Spleen QI deficiency with Cold-Damp retention
Clinical features as above, with sensation of bodily heaviness, heavy head, thick white tongue coat and persistent loose stools.
Treatment formula: Shen Ling Bai Zhu San
(Available as Irritable Bowel Formula or Ginseng & Atractylodes Formula)
- Spleen QI deficiency with Phlegm-Damp and Qi stagnation
Clinical features as above, with greasy tongue coat, bloating or epigastric distention, weak-slippery or weak-wiry pulse.
Treatment formula: Xiang Sha Liu Jun Zi Wan
(Available as Digestive Tonic Formula or Saussurea & Cardamon Formula)
Defense Qi deficiency
Key clinical features: Signs of Spleen Qi deficiency (as above), frequent upper respiratory infections, allergic rhinitis, spontaneous sweating, sensitivity to the cold and cold drafts (e.g. air conditioning causes discomfort or sneezing).
Treatment formula: Yu Ping Feng San
(Available as Defence Plus Formula or Jade Screen Formula)
Key clinical features: Robust patient, nausea, reflux or vomiting, a feeling of bodily heaviness, heavy head, bloating or epigastric distention, loose stools or diarrhea, flatulence, thick white or off-white tongue coat.
Treatment formula: Ping Wei San
(Available as Gut Detox Formula or Magnolia & Ginger Combination)
Turbid Damp invading Stomach and Spleen
Clinical features: acute condition (e.g. food poisoning), abdominal pain, nausea or vomiting, borborygmus, flatulence, diarrhea or constipation.
Treatment formula: Huo Xiang Zheng Qi Wan
(Available as Agastache Formula)
Qi stagnation in the Stomach and Intestines
Key clinical features: Disorders of gastro-intestinal motility, epigastric or abdominal dull pain with sensation of distention (pain is intermittent, of varying intensity and poorly localized), belching, acidic regurgitation, nausea or vomiting.
Treatment formula: Chai Hu Shu Gan Wan
(Available as Qi Mover Formula or Bupleurum & Cyperus Combination)
Stress related condition, with fatigue, anxiety or depressed mood.
Treatment formula: Jia Wei Xiao Yao San
(Available as Stress Relief 1 Formula or Bupleurum & Peony Formula)
Damp-Heat (retained in the Stomach and Intestines)
Key clinical features: Nausea and loss of appetite or excessive appetite, halitosis
loose stools are loose and malodorous, red tongue with a yellow coat.
Treatment formula: Huang Lian Jie Du Tang
(Available as Antitox 2 Formula or Coptis & Scute Formula)
Damp-Stagnation in the Liver and Gallbladder (with Liver-Spleen disharmony)
Key clinical features: Distending pain in the abdomen that is poorly localized and changes locations, pain is alleviated after passing stools or flatus, poor appetite or fluctuating appetite, loose stools or alternating constipation and loose stools, flatulence (which may be very malodorous).
Treatment formula: Yin Chen Hao Tang
(Available as Artemisia & Rhubarb Combination or WTM3 Body Shape Formula)
In terms of the weed and feed protocol, the appropriate Chinese herbal formulas are as follows:
- Gut Detox Formula a.k.a. Ping Wei San (Magnolia & Ginger Combination)
- Huo Xiang Zheng Qi Wan (Agastache Formula)
- Antitox 2 Formula a.k.a. Huang Lian Jie Du Wan (Coptis & Scute Formula)
- Yin Chen Hao Wan – Jia Wei (Artemisia & Rhubarb Combination)
- Qi Mover Formula a.k.a. Chai Hu Shu Gan Wan (Bupleurum & Cyperus Combination)
- Stress Relief 1 Formula a.k.a. Jia Wei Xiao Yao San (Bupleurum & Peony Formula)
- Energy Tonic Formula a.k.a. Bu Zhong Yi Qi Tang (Ginseng & Atractylodes Formula)
- Irritable Bowel Formula a.k.a. Shen Ling Bai Zhu San (Ginseng & Atractylodes Formula)
- Digestive Tonic Formula a.k.a. Xiang Sha Liu Jun Zi Wan (Saussurea & Cardamon Formula)
- Defence Plus Formula a.k.a. Yu Ping Feng San (Jade Screen Formula)
Note: All of the formulas discussed above are distributed in Australia and sponsored by Sun Herbal Pty Ltd
To return to the original thesis of this series of articles, I have attempted to show how TCM theories relating to the Spleen-Stomach, particularly those elaborated by Li Dong-yuan and his followers, correlate with contemporary research into the microbiome – specifically the composition of the intestinal microbiota and the integrity of the intestinal barrier. In some ways it appears that Western empirical research is just catching up with these Chinese medical theories and practices from the 13th century.
This may appear to be a bold statement in light of the colossal mountain of accumulating knowledge relating to the mechanisms linking dysbiosis and leaky gut with inflammatory, autoimmune, metabolic, neoplastic and neurodegenerative diseases. (25, 26, 27, 28, 29) The five citations from the previous sentence are recent review articles, each of which summarises the findings of around 100 to 200 original papers. Happily, most of the review papers in this field are available for download at no charge. Unfortunately, the standard of English expression appears to be uniformly poor, often making it extremely difficult for one to grasp some of the essential details without referring to the original papers cited (which, in turn may come with a price tag). That’s one caveat; there is one more. This is a relatively new field of study in which significant discoveries, some of which are of the order of a paradigm shift have been occurring on a regular basis. This expansion necessitates the use of many new technical terms, each of which requires a precise definition – otherwise we lose the level of precision required for a scientific discourse. Unfortunately, this is yet to happen, as there is no standardised nomenclature in this area. (30, 31) However, for readers who wish to explore these topics further, there is an excellent review paper published in 2017, which summarises the current knowledge on how the microbiome regulates and maintains human health. This paper, written in refreshingly good English summarises research, mostly from the past decade, and cites 440 references. (32)
The point that I wish to make is that in spite of the exponential growth in empirical research over the past 2 – 3 decades, the practical applications for everyday clinical use are quite thin on the ground. Appropriately, the last cited reference concludes with the following statement: ‘More focus on practical applications (sought by most funding organizations) along with empirical explorations once traditional to biology may offer two paths forward … (the need to) re-embrace the roots of traditional biological thought, where ecology, evolution and a focus on emergent principles in complex organisms can help re-center the pursuit of new knowledge and its applications to improve disease management and healthful lifespans.’ (italics, mine) (32) It looks like the authors are proposing a more holistic perspective (already familiar to complementary healthcare practitioners, including TCM), while looking forward to significant clinical applications in the future.
Part 4 will continue with an evaluation of important findings from recent scientific research, with a specific focus on small intestine bacterial overgrowth (SIBO).