Knowledge is Power: Anti-inflammatory and Antimicrobial Chinese Herbs


Inflammation is a part of the immune response that can prevent infection through production of pro- inflammatory cytokines and generation of inflammatory mediators in response to pathogens.[1]  Inflammation is an essential part of human immune response.  However, when the inflammatory process is poorly controlled, it can cause undesirable damages including massive tissue destruction. [2,3,4] 

Traditional Chinese Medicine (TCM) has been used in China for thousands of years for disease prevention and treatment.[6,8,9]  TCM uses yin–yang theory to explain the organizational structure, physiological functions, and pathological changes in the human body and to guide diagnosis and treatment of disease.[5,10]  TCM theory states that keeping balance between yin and yang is important to maintain the healthy state of human body.  Therefore, in TCM, inflammatory and antimicrobial therapy depend upon strengthening the body defense system to keep a balanced between yin and yang. [5,11] 

Herbal medicine is one of the main components of TCM treatment system.  TCM herbs used in treating diseases are grouped into several categories.  The anti-inflammatory and anti-viral herbs are considered to be antipyretic. [11,13]  This blog summarize the effect and mechanism of action of common anti-inflammatory and anti-viral TCM herbs.

Scutellaria baicalensis (黃芩 Huáng Qín) 

Scutellaria baicalensis is a species of flowering plant belonging to Lamiaceae family It is a heat-clearing, phlegm-removing herb, traditionally used to cool inflammation, reduce fever, and stop bleeding.[11,13,14] The root part of Sc. baicalensis has pharmacological effects including antipyretic, hepatoprotective, antihypertensive, diuretic, and antibiotic activities. It is mildly sedating and also used to treat dysentery and chronic hepatitis. [6,7,14,15].  Sc. baicalensis is found to be effective in treating inflammatory diseases.  Modern pharmacological studies have shown that the herb alleviates inflammation by decreasing the expression of interleukin (IL)-1b, IL-6, and IL-12, and the production of tumor necrosis factor (TNF)-α and soluble intercellular adhesion molecule-1 (ICAM-1).[5,16]  In some traditional TCM formulations,  huang qin, in combination with huang lian, inhibits nitric oxide (NO) production in vitro and in vivo in lipopolysaccharide (LPS)- stimulated RAW264.7 cells. Oroxylin A, which is a flavonoid found in dried root of Sc. baicalensis, has also shown good anti-inflammatory effect. [17,18]  Moreover, Sc. baicalensis has antibacterial effect against Helicobacter pylori as well as inhibits the growth of Escherichia coli B, coagulase-negative staphylococci, and Saccharomyces cerevisiae.[7,15] 

Coptis chinensis (黃連 Huáng Lián) 

Coptis chinensis belongs to Ranunculaceae family. Traditionally, it has been used to reduce inflammation, reduce fever, detoxify and disinfect, stop bleeding, cure eczema, burns, and ulcer.[7,11,13,14,19] The herb has long been recognized in the treatment of intestinal infections including acute gastroenteritis, cholera, and bacillary dysentery. It also used for treating various diseases including skin diseases, conjunctivitis, otitis, and hypertension. [14,19,20]  

C. chinensis has been demonstrated to have anti-inflammatory effects through different mechanisms.  Reseaches have shown that the herb inhibits TNF-induced Nuclear factor-kappaB (NF-kB) signaling in human keratinocytes by blocking the NF-kB–dependent pathway.  It also decreases Th17 cytokine secretion and differentiation by activation of extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) and down-regulation of phosphorylated signal transducer and activator of transcription 3 (p-STAT3) and retinoic acid-related orphan receptor Υt (RORγt) expression. It also reduces Th1 cytokine secretion and differentiation by inhibition of protein 38 (p38) mitogen activated protein kinase (MAPK) and Jun N-terminal kinase (JNK) activation along with down-regulation of STAT1 and STAT4 activities. [21,22] 

In combination with other herbs, C. chinensis exhibited a good anti-inflammatory effect; the ethanol extract from Zuojin Pill inhibited inducible nitric oxide synthase (iNOS), cyclooxygenase 2 (COX- 2), IL-6, IL-1β, and TNF-α expression by preventing the nuclear translocation of the NF-κB p50 and p65 subunits in RAW 264.7 cells.[23]   

C. chinensis also exhibits significant antimicrobial activity against a variety of microorganisms including bacteria, viruses, fungi, protozoans, helminths, and Chlamydia, including Staphylococcus aureusPseudomonas aeruginosaE. coliPropionibacterium acnesStreptococcus pneumoniaeVibrio choleraeBacillus anthracisBacillus dysenteriae, and Sa. cerevisiae. [7,21,25]  Berberine, the major active component of C. chinensis, was found to be bactericidal on V. cholera and capable of inhibiting bacterial adherence to mucosal or epithelial surfaces.[26] 

Flos Lonicerae (金銀花 Jīn Yín Hūa) 

Flos lonicerae is a honeysuckle flower belonging to Caprifoliaceae family. It is a widely used in China for treating respiratory infection and diseases.[11,14,27,28]  The dried flower and buds of Flos Lonicerae have shown various pharmacological effects including anti- nociceptive, anti-diabetic, anti-tumor, antioxidant, anti-angiogenic, antipyretic, antiviral, and hepatoprotective activities.[6,29,30,31]  

Flos Lonicerae demonstrated anti-inflammatory properties through suppression of mediator release from the mast cells activated by secretagogues.[32]  In addition, the n– butanol fraction containing Flos Lonicerae can alleviate inflammation better than celecoxib in carrageen- and croton oil-induced paw edema and ear edema.[29].  Flos Lonicerae contains various active compounds that have marked anti-inflammatory effect, including luteolin (suppresses inflammatory mediator release by blocking NF-kB and MAPKs pathway activation in HMC-11 cells), chlorogenic acid (inhibits rat reflux esophagitis induced by pylorus and forestomach ligation), and loncerin (reduces edema by suppressing T cell proliferation, NO production from the macrophages, and shifting cellular immunity from Th1- toward Th2-type responses).[33,34,35].  Flos Lonicerae has significant antimicrobial activity against diverse species of bacteria and fungi. It has inhibitory effect against H. pylori and Porphyromonas gingivalis,[15] and it treats candidal septic arthritis.[35]  It also has antimicrobial effect against oral pathogens including Streptococcus mutansActinomyces viscosus, and Bacteroides melaninogenicus.[6] 

Forsythia suspensa (連翹 Lián Qiào) 

Forsythia suspensa is a flowering plant belonging to the family Oleaceae. Traditionally, it is used to treat cold and flu. [11,13,14]  The fruit of F. suspensa has potent pharmacological actions such as antiviral, choleretic, antipyretic, hepatoprotective, antiemetic, and diuretic effects.[14,27]. F. suspensa alleviates inflammation by reducing the anaphylactic antibodies, mast cell degranulation, and histamine release.  It also significantly suppresses β-conglycinin–induced T lymphocyte proliferation and IL-4 synthesis. [36,37]. F. suspensa fruit inhibits NO production and iNOS gene expression by its active components rengyolone, dibenzylbutyrolactone lignans, as well as its butanol fraction of the aqueous extract.  It also inhibits TNF-α and COX-2 production.[38,39,40]  One active component of the herb, arctigenin, inhibits increase in capillary permeability and leukocyte recruitment into inflamed tissues, by reduction of the vascular leakage and cellular events through inhibition of production of inflammatory mediators such as NO and pro-inflammatory cytokines such as IL-1b, IL-6, TNF-α, and prostaglandin E2 (PGE2).[38,39,41]

Moreover, F. suspensa inhibits NF-kB nucleus translocation through reduction in I-kappa-B (IkB) phosphorylation and suppression of NF-kB–regulated proteins, and also reduces the activation of MAPKs. [39,40,41]  Various studies have reported the antimicrobial effect of F. suspensa. It has potent antibacterial activity against E. coli, Sta. aureus, Bacillus subtilis, Str. mutans, and Po. gingivalis and antifungal activity against Aspergillus flavus, Rhizopus stolonifer, Penicillium citrinum, Aspergillus niger, and Saccharomyces carlsbergensis.[6,42]. F. suspensa suppresses influenza A virus– induced RANTES secretion by human bronchial epithelial cells to stop accumulation of inflammatory cells in the infective sites, which has been reported to play a crucial role in the progression of chronic inflammation and multiple sclerosis after viral infection.[27] 

Isatidis folium ( Dà Qīng Yè) 

Isatidis folium is a flowering plant belonging to the family Brassicaceae. The leaves of Isatidis Folium are traditionally used for the treatment of sore throat, redness of skin, and as an antipyretic. [13,14,27,43,44]. Isatidis Folium has also been used to treat encephalitis, acute dysentery, hepatitis, measles, pneumonia, influenza, epidemic cerebrospinal meningitis, encephalitis B, viral pneumonia, mumps, and diabetics. [27,45,46]   

Tryptanthrin, an alkaloid isolated from Isatidis leaves, has shown anti- inflammatory effect due to its strong inhibitory effect on the COX-2 enzyme.[47] Several derivatives of hydroxycinnamic acid, including ferulic acid and sinapic acid, are also thought to be important to inhibit inflammation.[25]. Isatidis Folium possesses valuable viricidal effect in the control of pseudorabies infection in swine.[48,49] 

Radix Isatidis (板藍根 Bǎn Lán Gēn) 

Isatidis radix belongs to the family Brassicaceae. Traditionally, it used to reduce inflammation, reduce fever and to treat encephalitis B and viral infections such as cold and flu.[13,14,19] The dry root of Isatidis Radix has pharmacological activities such as antibiotic, anti-diabetic, and immune- stimulating effects.[48,50]  Methanolic extracts of Isatidis Radix can significantly inhibit the release of inflammatory mediators from the macrophages, such as NO, PGE2, and pro-inflammatory cytokines.[51]  Isatidis Radix has also been demonstrated to suppress the growth of E. coli and H. pylori and increases blood neutrophil phagocytosis of P32-labeled Sta. aureus. [15,52,53]  Syringic acid isolated from Isatidis Radix inhibited LPS-induced endotoxin shock.[51]  Besides, Isatidis Radix is found to be clinically effective against the infections caused by various subtypes and strains of influenza viruses including Severe Acute Respiratory Syndrome (SARS).[44,50]

Viola yedoensis (紫花地丁 Zǐ Huā Dì Dīng) 

Viola yedoensis is a flowering plant belonging to the violet family of Violaceae. Traditionally, it used to reduce inflammation, reduce fever, and disinfect and detoxify. [11,13,14]. V. yedoensis has several pharmacological effects including antibiotic, anti-inflammatory, and antipyretic activities.  It can also be used for the treatment of skin diseases, i.e. eczema, impetigo, acne, pruritus, and cradle cap, and for upper respiratory tract infections with fever. [12,14]  It has been reported to have antimicrobial activity against B. subtilis, Str. mutans, and Po. gingivalis.[54]  Modern researchers have shown that the herb inhibits the replication of herpes simplex virus-1 and enterovirus 71 in the human neuroblastoma SK-N-SH cell line.  Cyclotides from Viola are shown to be effective in inhibiting human immunodeficiency virus (HIV) replication.[50,55] 

Pulsatilla radix (白頭翁 Bái Tóu Wēng) 

Pulsatilla radix is a medicinal root plant of the Ranunculaceae. It used to reduce fever, disinfect and detoxify, and clear damp-heat in TCM. [13,14]  The root of Pulsatilla Radix has anti-inflammatory, antiparasitic, and antimicrobial action. It can treat dyspepsia, premenstrual tension, and psychosomatic disturbances.[14] A quinine-type compound, pulsaquinone, isolated from the aqueous ethanol extract of the roots of Pulsatilla Radix exhibited antimicrobial activities against an anaerobic non–spore-forming gram-positive bacillus, Pr. acnes, which is related to the pathogenesis of the inflamed lesions in a common skin disease, acne vulgaris.[56] Moreover, 4-hydroxy-3-methoxycinnamic acid of Pulsatilla Radix is found to have a selective growth inhibitor of the human intestinal bacteria, Clostridium perfringens and E. coli.[57] 

Andrographis paniculata (穿心蓮 Chuān Xīn Lián) 

Andrographis paniculata is also known as nemone chinensi and belongs to Acanthaceae family.[11] The active compounds isolated from An. paniculata, including diterpene, lactone, and andrographolide, have shown anti-inflammatory, anti-allergic, immune-stimulatory, and antiviral activities.[58,59]  An. paniculata alleviates inflammation by inhibiting iNOS, TNF-α, IL-1b, IL-6, and IL-12 expression and NO production by down-regulation of p38MAPKs signaling pathways.[5,60] It also suppresses influenza A virus-induced RANTES secretion by human bronchial epithelial cells.[27] 

Houttuynia cordata (魚腥草 Yú Xīng Cǎo) 

Houttuynia cordata is one of the two species in the genus Houttuynia and belongs to the family Saururaceae.[14] It has pharmacological effects including immune-stimulating, anti-inflammatory, antibiotic, antiviral, diuretic, analgesic, and hemostatic effects. It also used to treat pneumonia, bronchitis, colitis, urogenital tract infections, and chronic obstructive respiratory diseases, and topically to treat herpes simplex.[61] 

Patrinia Herba (敗醬草 Bài Jiàn Cǎo) 

Patrinia herba is a medicinal herb belongs to family of Valerianaceae.[12,14]  It has antibiotic, hepatoprotective, sedating, and hypnotic effects, and it can be used to treat mumps.[14]. Patrinia Herba can inhibit adjuvant-induced inflammation and hyperalgesia.  In rats, it has shown to attenuate Freund’s adjuvant (CFA)– induced hyperalgesia and facilitates the recovery from hyperalgesia, and also reduces edema.[62] 


Various studies have revealed that these anti-inflammatory and anti-viral herbs are used for treating inflammatory and microbial diseases due to their multiple active ingredients.  Since inflammation is the result of interaction of various inflammatory mediators, these anti-inflammatory and anti-viral herbs can exert anti- inflammatory effect through different mechanisms of action including inhibition of inflammatory cytokines and mediators, blocking of inflammatory signaling, and interfering with chemokines.  Moreover, these anti-inflammatory and anti-viral herbs have also shown antimicrobial effect through inhibition of microbial adherence to mucosal or epithelial surfaces, inhibition of endotoxin shock, and selective inhibition of microbial growth.  Collectively, all the above mechanisms are likely to be important for the anti-inflammatory and antimicrobial activity of these anti-inflammatory and anti-viral herbs.  This blog reveals the anti-inflammatory and antimicrobial effects of these anti-inflammatory and anti-viral herbs, in general, from different aspects and through different mechanisms. This may be linked to their action of reducing inflammation, reducing fever and counteracting toxicity. 

Thanks for reading.

Note: This blog post is adapted from J Tradit Complement Med. 2014 Apr-Jun; 4(2): 93–98. doi: 10.4103/2225-4110.126635: 10.4103/2225-4110.126635 


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