Title : Indigenous aspalathus linearis extracts as an alternative to conventional treatment of gut-related inflammatory conditions
Abstract:
Background: Dysfunction of the intestinal epithelium can result in increased gut permeability causing deregulated transport across the cell membrane as well as cell-to-cell communication resulting in gastrointestinal (GI) disease. The precise regulation of the intestinal barrier allows the maintenance of mucosal immune homeostasis and prevents the onset of inflammation. Generally, anti-inflammatory or immunosuppressive drugs are used as the first line of treatment, however, steroids and non-steroid anti-inflammatory drugs (NSAIDs) are efficient in temporary relief of symptoms but long-term usage could elicit adverse side effects. Therefore, research turns to traditional plant-based medication for a more natural yet effective answer. Aspalathus linearis commonly known as Rooibos is an herbal tea produced from the leaves and stems of the indigenous South African plant known for its many health-promoting properties such as aiding in digestion and alleviation of inflammation. Additionally, rooibos is rich in unique polyphenols making it an interesting choice for phytomedicine.
Aim and objective: Investigate the cytotoxic, apoptotic and anti-inflammatory effects of aqueous unfermented (RgU) and fermented (RgF) rooibos extracts on LPS-induced porcine intestinal epithelial cells (IPEC-J2). Additionally, the study investigates the effects of the rooibos extracts on gene expression, specifically barrier integrity markers thereby analyzing the barrier restorative effects.
Methods: Aqueous rooibos extracts were prepared by lyophilization and characterized by High-performance liquid chromatography (HPLC) and antioxidant analysis. Lipopolysaccharide (LPS) was used to induce inflammation in the model with dexamethasone as a comparative anti-inflammatory control. The cytotoxicity and protective effects of the rooibos extracts were determined by assessing cell viability (ATP), apoptosis (caspase assay), inflammation (enzyme-linked immunosorbent assay) and gene expression (quantitative polymerase chain reaction).
Results: HPLC analysis showed that unfermented extracts contained higher levels of total polyphenols (14.2 g/100g). Subsequently, the processing of the extracts showed significant changes in the content between unfermented and fermented extracts. The optimal dexamethasone concentration of 0,15625 mM was selected for the model. The RgU and RgF extracts demonstrated anti-inflammatory properties (p<0.05). Additionally, gene expression analysis showed the extracts have significant barrier restoring effects on IPECJ2 cells.
Conclusion: Processing of the tea affects the phenolic content which are associated to the biological activity. The extracts demonstrated protection against LPS-induced inflammation, thereby displaying the potential to restore and increase intestinal barrier integrity on IECs. When comparing the extracts to dexamethasone, tea extracts were significantly more superior in reducing IL-8 in LPS-induced inflammation condition and therefore the current results show the potential of rooibos as a natural alternative supplement for preventing gut-related inflammatory conditions. The study showcases the value of South African indigenous plants and how diversely it can be utilized.
Audience Take Away:
- The study will provide valuable information about the benefits of indigenous plants specifically Rooibos, and possibly began incorporating it into their daily lives.
- This research also provides a stepping stone for many more in-depth investigations into gut-health and gut-related problems.
- This study will give more information on the intricate mechanisms or where and how rooibos works and elicits its health promoting properties.
- The methods and analysis can be used to investigate other potential indigenous species.
- The audience will learn more in-depth knowledge about Rooibos and its many other possibilities outside the area of gut-health.
