
Ban Lan Gen, Indigo wood
Ban Lan Gen Chong Ji
Derived from the root of the isatis plant, a source of indigo dye. This botanical has been used for thousands of years in traditional Chinese medicine and Ayurvedic medicine. It is used in combination with other herbs to treat common cold, sore throat, mumps, respiratory aliments, other febrile diseases and malignant tumors (1) (2). The leaves of this plant are one of the eight ingredients used in PC-SPES, an herbal formula used to treat prostate cancer. Isatis root is also used in Danggui Longhui Wan, a formula used to treat chronic myelocytic leukemia (CML) in China (3).
Isatis root exhibited antimicrobial (4), antiviral (1) (5) immunostimulatory effects (3) (6), and radioprotective effects (8)in vitro and in animal studies. Anecdotal reports show that isatis root can be used to ward off severe acute respiratory syndrome (SARS) (9).
Isatis root eyedrops were shown effective in the treatment of bacterial conjunctivitis (4)and a small randomized clinical study demonstrated its utility in reducing the severity of radiation mucositis (7).
Isatis root extract has anti-inflammatory, antipyretic and antinociceptive effects on animals (8) (10). Extracts obtained from the dried leaves of isatis have cyclooxygenase-2 (COX-2) inhibitory effects (11). Isatis root also has immunostimulatory effects by enhancing reticuloendothelial system function. One animal study found that indigo root extract reduced tissue injury, enhanced hematopoietic system recovery, modulated serum inflammatory cytokines, and improved severe enteropathy in whole body irradiated mice (8). An in vitro study also found that an ethanol extract of isatis root had a dose-dependent cytotoxic effect against human leukemia HL-60 cells (12). Indirubin, an active component of isatis, is a potent inhibitor of cyclin-dependent kinases (CDKs). It inhibits the proliferation of cells by arresting the cells in the G2/M phase (3). Other alkaloids isolated from isatis can inhibit leukocyte function and reduce inflammatory response (13). Some studies show that isatis also has antiviral activities (5) (12).
The effect of isatis or Ban Lan Gen on severe acute respiratory syndrome (SARS) is not known. Patients are warned that reliance on herbal supplements as prevention or treatment may induce a false sense of security from this deadly disease. Patients with suspected SARS should limit interactions outside the home. The Centers for Disease Control (CDC) recommend that proper hygiene such as frequent hand washing and wearing a surgical mask can help prevent the spread of SARS (14).
None reported.
You WC, et al. Effect of extracts from indigowood root (Isatis indigotica Fort.) on immune responses in radiation-induced mucositis. J Altern Complement Med. 2009 Jul;15(7):771-8.
This study investigated the effect of indirubin (taken as isatis root powder) on acute radiation-induced mucositis. Twenty patients who were receiving radiation therapy for head and neck cancer were enrolled and randomized into a control or treatment group. The treatment group gargled with a solution made from indigowood root powder dissolved in double-distilled water for three minutes, and then swallowed it, before meals daily for seven weeks. The results of the clinical trial indicated that indigowood root significantly reduced the severity of radiation mucositis (p=0.01), anorexia (p=0.002), and swallowing difficulty (p=0.002) in treated patients compared to the control group. The authors concluded that indirubin may play a therapeutic role in improving radiation-induced mucositis, anorexia, and difficulty swallowing, but that the exact mechanism and pathways should be further studied.
Qi CX, Wu XM, Wang XL. Clinical research of isatis root eyedrops on the acute bacterial conjunctivitis. Zhong Yao Cai. 2007 Jan;30(1):120-2
This randomized, double-blind, parallel study evaluated the efficacy and safety of isatis root eyedrops on 200 cases of acute bacterial conjunctivitis. Patients received either isatis root or levofloxacin eyedrops (as a test and control agent, respectively), six times a day for 7 days. The efficacy rate in the isatis root and levofloxacin groups was observed to be 90% and 93%, respectively, a difference which was not statistically significant (p>0.05). Two patients experienced side effects. The investigators concluded that isatis root eyedrops exhibited an excellent efficacy and safety profile in the treatment of acute bacterial conjunctivitis.
Bottom Line: Isatis root has not been extensively studied in clinical trials, so it is not known if it works in humans.
Isatis root extract is derived from the same plant from which indigo dye is made. It has been used in combination with other botanicals in traditional Chinese and Ayurvedic medicine for thousands of years. In animal tests, this root extract reduced inflammation, fever, and perception of pain. Isatis root also was able to stimulate the immune system of laboratory mice by enhancing the activity of the reticuloendothelial system (the stationary immune cells in the liver, spleen, and other tissues that swallow and destroy foreign particles as they pass in the bloodstream). Laboratory studies have also suggested that indirubin, an active component of isatis root, inhibits the replication of dividing cells and therefore may be useful in cancer treatment. In the laboratory setting, isatis extracts are able to kill certain viruses and counteract the effects of endotoxin, which causes some of the symptoms and tissue damage of bacterial infections. However, this botanical has not yet been evaluated in clinical trials and therefore it remains uncertain whether these effects occur in the human body.
Radiation-induced Mucositis
Twenty patients who were receiving radiation therapy for head and neck cancer were randomized into control or treatment groups. The treatment group gargled with a solution made from indigowood root powder dissolved in double-distilled water for three minutes, and then swallowed it, before meals daily for seven weeks. Indigowood root significantly reduced the severity of radiation mucositis, anorexia, and difficulty in swallowing in treated patients compared to the control group.
Acute Bacterial Conjunctivitis
Two hundred patients with Acute Bacterial Conjunctivitis received either isatis root or levofloxacin eyedrops, six times a day for 7 days. The efficacy rate in the isatis root and levofloxacin groups was observed to be 90% and 93%, respectively, a difference which was not statistically significant. Two patients experienced side effects. Investigators concluded that isatis root eyedrops may be useful in the treatment of acute bacterial conjunctivitis.
None known