The herb Scutellaria baicalensis (also called Baikal or Chinese skullcap) is traditionally used to treat various ailments, such as diarrhoea, insomnia, hypertension, and inflammation. Today, modern medicine continues to use this herb to treat those ailments, even extending to cancers.

Pharmacological characterisation of Baikal skullcap has identified four main bioactive components: baicalin, baicalein, wogonoside and wogonin. Impressively, each of these compounds has been found to elicit anticancer activities through a myriad of mechanisms, depending on the type of cancer, which ranges from prostate to brain cancers.

For example, treating mice with prostate cancer with Baikal skullcap extract or baicalein shrunk tumour size by half in just a few weeks. Further research showed that baicalein and wogonin could stop androgen signalling essential to prostate cancer cells, resulting in apoptotic cell death. Wogonin can even sensitise prostate cancer cells to being attacked by the immune system, specifically by tumour necrosis factor (TNF) that immune cells secrete. This sensitisation effect has also been observed in wogonin-treated breast cancer cells. More recent studies showed that baicalin and baicalein could hamper the β-catenin and estrogen signalling, respectively, preventing the breast cancer from growing and spreading to the lungs and liver in mice.

Baikal skullcap or its bioactive compounds have also been used in clinical trials involving cancer patients (i.e., lung, colon, and pancreatic cancers) without any toxicity concerns, meriting its application to other types of cancers as well. Indeed, clinical trials have been conducted on the capacity of Baikal skullcap in modulating the human microbiota via its antimicrobial and anti-inflammatory properties. For example, gargle solutions or toothpaste enriched with Baikal skullcap extract modulated the oral microbiota, inhibited the growth of oral pathogens, and reduced the formation of gingival plaques. Additionally, in patients with type 2 diabetes, co-treatment with metformin and Baikal skullcap extract led to favourable gut microbiota changes, improving energy metabolism glucose tolerance compared to metformin alone.

Interestingly, pre-clinical research continues to uncover the potential use of Baikal skullcap in treating vascular diseases. Specifically, baicalin has been found to mitigate the expression of adhesion molecules, such as intercellular and vascular cell adhesion molecule-1 (ICAM-1 and VCAM-1), thus preventing immune cells from sticking to and inflaming blood vessel walls. Another vascular action of baicalin is its ability to inhibit platelet hyperactivity. As platelets are responsible for blood clotting, their overactivity can form excessive clots, which may cause severe complications such as stroke, heart attack and deep vein thrombosis. Overall, the anti-thrombotic activities of Baikal skullcap deserve further clinical investigation.

Cover Image Attribution:“2016.08.19_13.52.15_DSC05593” by Andrey Zharkikh is licensed under CC BY 2.0