Specialist scientist at the South African Medical Research Council (SAMRC)
"Toxicity screening is essential for anything that may be consumed by humans."
Tracking toxicity in honeybush tea
Toxicity screening is necessary for anything that may be ingested by humans, including honeybush tea. I am assessing the effects of the compounds or chemicals present in honeybush on the human liver. The liver is the organ responsible for detoxification in the body. Thus, if something is harmful or toxic in the body, the liver will reveal the early effects.
Why this matters
With the development of honeybush as a commercial product, laboratory-based cell culture (in vitro) screening of its various components is needed. So far, honeybush has been consumed by millions of people, with no adverse health effects reported. However, researchers need to make sure that honeybush tea products remain safe for human consumption. At present, there is no scientific evidence to support claims that there are no harmful side-effects. In vitro testing is needed as a first-line screening method before consent is given for product testing or usage in animals or humans.
About the researcher
Chellan is currently specialising in research on pancreatic beta cells and type 2 diabetes. Beta cells are unique cells in the pancreas that produce, store and release the hormone insulin.
Chellan's niche research field revolves around the pathophysiology (disordered functioning of organs) of type 2 diabetes in pancreatic beta cells, which includes decreased production of the hormone insulin. Chellan uses different techniques to track changes in gene and protein expression in these beta cells. She also explores key functional pathways in these cells. She uses techniques such as qRT-PCR, fluorescent imaging, tissue processing, flow cytometry, PBMC and islet isolations and glucose metabolism assays. Chellan also does laboratory-based in vitro toxicity testing and has established, in collaboration with Danish co-workers, a novel three-dimensional screening model for this.
Chellan started her scientific journey by obtaining a BSc degree from the University of Natal in 2005, followed by a BSc Honours (cum laude), an MSc degree (cum laude) and a PhD in medical physiology from Stellenbosch University. Her PhD research focused on honeybush. She focussed on the effect of Cyclopia maculata extract on beta cell function, protection against oxidative stress in cells (the imbalance between free radicals and antioxidants in the body), and cell survival.
Dr Nireshni Chellan, a specialist scientists at the South African Medical Research Council (SAMRC), is tracking the effects of components of honeybush on the human liver to ensure it causes no chemical-driven liver damage.