Modern Australian
The Times Real Estate

.

Hong Kong Baptist University joint research reveals that gut microbial enzymes reactivate triclosan which induces colitis

HONG KONG SAR - Media OutReach - 3 May 2022 - A Hong Kong Baptist University (HKBU) collaborative research study has revealed that certain gut microbial enzymes mediate the reactivation of triclosan (TCS) from its inactive glucuronide metabolite.

TCS is an antimicrobial agent commonly used in a wide range of consumer products, and it is associated with the development of colitis.

Professor Cai Zongwei, Chair Professor of the Department of Chemistry and Director of the State Key Laboratory of Environmental and Biological Analysis at HKBU, points out that according to the research results specific gut microbial enzymes drive the conversion of TCS metabolites to TCS which increases the chance of developing colitis.
Professor Cai Zongwei, Chair Professor of the Department of Chemistry and Director of the State Key Laboratory of Environmental and Biological Analysis at HKBU, points out that according to the research results specific gut microbial enzymes drive the conversion of TCS metabolites to TCS which increases the chance of developing colitis.

The research results have been published in Nature Communications, an international scientific journal.

Mechanism of TCS exposure leading to colitis previously unclear

TCS is widely used as an antimicrobial agent in consumer products such as toothpaste, mouthwash, hand sanitisers, cosmetics and toys. It is a major environmental contaminant, and it has been shown that TCS exposure increases the risk of colitis.

Once TCS enters the human body, it is rapidly metabolised to form the biologically inactive metabolite TCS-glucuronide (TCS-G), which is easily eliminated from the body. Due to this characteristic, the mechanism of how environmental exposure to TCS leads to gut toxicity in the human body has previously remained unclear.

To answer this question, a research team co-led by Professor Cai Zongwei, Chair Professor of the Department of Chemistry and Director of the State Key Laboratory of Environmental and Biological Analysis at HKBU; Professor Matthew R Redinbo from the University of North Carolina at Chapel Hill; and Professor Zhang Guodong from the University of Massachusetts Amherst conducted a research study based on the hypothesis that certain gut microbial enzymes act on TCS-G in the gut, leading to the reactivation of TCS and the subsequent development of colitis.

TCS concentration uniquely high in the gut

To begin with, the research team sought to determine whether the gut has a different TCS metabolic profile compared to other body tissues. A group of mice were fed food that contained TCS. After four weeks, it was found that the biologically inactive TCS-G was dominant in their liver, bile, heart and small intestine, while the colitis-inducing TCS was dominant in the gut (cecum and colon). The results showed that the gut has a uniquely high concentration of TCS compared to other body tissues.

The research team then analysed the relationship between TCS-containing products and the concentration of TCS in the human body. In a group of human subjects who used TCS-containing personal care products for four months, both TCS and TCS-G were detected in their stool and urine samples, with TCS being dominant in stool and TCS-G being dominant in urine. However, TCS and TCS-G were not detected in the control group who used TCS-free personal care products. The results showed that the use of TCS-containing products leads to a high level of TCS, specifically in the human gut.

Gut microbiota significant in TCS-G conversion

The question remains why the human gut has a uniquely high TCS concentration. To answer this, the research team put forth the hypothesis that gut microbiota participate in the conversion of TCS-G to TCS, leading to the accumulation of TCS in the gut.

To test this hypothesis, the researchers observed that in an in vitro setting, cultured gut bacteria from both mice and humans were able to catalyse the conversion of TCS-G to TCS. To investigate whether the same phenomenon appears in an in vivo setting, the research team found that the inhibition of gut bacteria from mice by applying an antibiotic treatment almost reduced the concentration of TCS in their guts by half, and it increased the concentration of TCS-G by six-fold. The results affirmed that gut microbiota play a significant role in the conversion of TCS-G to TCS in the gut.

Specific enzymes catalyse TCS-G conversion

To investigate the mechanism by which gut microbiota catalyse TCS-G conversion, the research team focused on the intestinal β-glucuronidase (GUS) enzymes produced by gut bacteria in both mice and humans, because they have been shown to catalyse a wide range of metabolite conversions. Using a series of screening techniques, two types of GUS, namely "Loop 1" and "flavin mononucleotide (FMN)-binding" GUSs, were found to be most effective at converting TCS-G to TCS in vitro.

The research team then applied a GUS inhibitor, a drug that inhibits the function of Loop 1 and FMN-binding GUSs, to TCS-exposed and TCS-free mice. It was found that the GUS inhibitor could curb the conversion of TCS-G to TCS by the GUS enzymes. Colitis in TCS-exposed mice was also relieved after the application of the GUS inhibitor. The results support the notion that specific microbial GUS enzymes drive the conversion of TCS-G to TCS, and as a result, the chance of developing colitis is increased.

More stringent TCS controls needed

Professor Cai said: "Our research results clearly defined the mechanism by which gut microbiota are involved in the metabolism and toxicology of TCS, and the study offers a way to prevent the development of colitis following environmental exposure to chemicals.

"Regulatory bodies should consider imposing more stringent controls on the use of TCS. Although the US Food and Drug Administration (FDA) banned the marketing of TCS in over-the-counter antiseptic products in 2016, the chemical remains approved for use in a wide range of products. Transparency on TCS ingredients in product labelling and illustrations should also be improved so that consumers can be aware of the potential risks and make informed choices."

#HongKongBaptistUniversity #HKBU

Davines Sustainable Haircare: Revolutionizing Eco-Friendly Beauty Solutions

Davines is a well-known brand in the world of haircare, known for its high-quality products that deliver exceptional results. Its commitment to sust...

The Role of CDNs in Enhancing Headless CMS Performance and Reliability

A headless CMS provides businesses with the ultimate freedom for content management and output possibilities across any number of channels. However...

Finding the Right Dentist in Perth for Your Dental Implants: A Complete Guide

Missing teeth can significantly impact your quality of life, affecting everything from your ability to eat and speak to your self-confidence. Dental...

Fix These 5 Technical SEO Issues Hurting Your Perth Business Rankings

Perth businesses face unique challenges when competing for visibility in local search results.  While many business owners focus on content creati...

How a Professional Bookkeeper Can Help Your Small Business

Running a small business in Australia comes with many responsibilities, from managing day-to-day operations to ensuring compliance with tax and fina...

How Pre-Employment Drug Testing Can Improve Your Company’s Culture

When it comes to curating a thriving workplace, culture is everything. It is the glue holding teams together, the driving force behind productivity...

How To Find Comfortable And Stylish Armchairs Online

Shopping online can be tricky, particularly when it comes to buying furniture. All homeowners, including you, want an armchair that is stylish and c...

Rope Rescue Training Explained: Techniques, Tools & Skills

Rope rescue training is critical for emergency responders, industrial workers, and anyone who operates in high-risk environments. Whether you're a fir...

The Different Career Paths in a Law Firm: From Clerk to Partner

The legal profession offers a structured yet diverse career path, with opportunities ranging from entry-level positions to esteemed leadership roles...

The Importance of Exercise for People with Disabilities: Adaptive Workouts

Exercise is a fundamental part of maintaining physical and mental wellbeing, and this holds true for people of all abilities. For individuals with d...

Planning a Construction or Renovation? Don’t Overlook the Plumbing!

Building or renovating your home is an exciting journey—designing layouts, selecting finishes, and watching your space come to life. However, while ...

Bathroom Tiling: Trends, Materials and Installation Tips

The world of bathroom tiling has come a long way, with new trends, improved materials, and innovative installation techniques, making it easier than...

Best Products to Increase Hair Density: What Really Works?

Do you want thick, voluminous hair? We get you!! There’s just something about a full head of hair that makes you feel more confident. But what do...

The Cost of Back to Base Security in Sydney: Is It Worth the Investment?

Sydney is a fantastic place to live. The beaches, the cafes, the culture. There’s a reason people are willing to pay premium prices for a spot in ...

Australian Workplace Engagement Declines Amidst Shifting Employee Priorities

Global leader in employee engagement and HR technology, Reward Gateway, has today released its second annual Workplace Engagement Index. The report...

The Right Mix: 5 Tips for Choosing Products Your Customers Will Love

Photo: Marcella Marcella / Unsplash Crafting the perfect product offering is difficult. You need to strike a delicate balance between building a busi...

Septic Tank Pump Out Cost: What to Expect in 2025

The size of the tank, the location and the rates charged by the service provider all affect how much a septic tank pump out will cost. Every thre...

How Machine Learning is Personalizing Orthodontic Treatment

Orthodontic treatment has seen a significant transformation over the past few decades, largely due to advancements in digital dentistry and artificial...