Latest News Archive

Please select Category, Year, and then Month to display items
Previous Archive
20 September 2024 | Story André Damons | Photo Supplied
zebrafish-blue-in-aquarium
Zebrafish blue in an aquarium.

A researcher from the University of the Free State (UFS) hopes to make living with epilepsy and other diseases of the central nervous system (CNS) easier by using South African plants extracts which may have anti-epileptic properties and testing them on zebrafish larvae.

Prof Anke Wilhelm, Associate Professor and Divisional Head of Organic Chemistry in the UFS Department of Chemistry, focuses her research on the isolation of active GABAergic compounds (substances that affect the brain’s GABA system, which helps control nervous system activity) by using a test that measures the movement of zebrafish larvae.

Even though obtaining regulatory approval for use as a treatment for epilepsy is a long and complex process, Prof Wilhelm hopes to contribute to the better pain management of people suffering from epilepsy and diseases of the CNS through an affordable alternative drug with less side effects.

The tests are done in a zebrafish bioassay (an analytical method to determine the potency of a substance by its effect on living animals) housed at the UFS’ Chemistry Department.

Why zebrafish larvae?

Prof Wilhelm, who is a National Research Foundation Y2-rated synthetic organic chemist, says zebrafish share about 70% of their genes with humans, and about 84% of human genes known to be associated with diseases have a counterpart in zebrafish. This makes them a valuable model for studying human biology and disease.

“Zebrafish are powerful tools for modelling a wide range of CNS diseases, contributing significantly to the understanding of disease mechanisms and the development of potential treatments,” she says. “Mood disorders, anxiety, insomnia, and attention deficit hyperactivity disorder (ADHD) are all diseases which may be studied through this bioassay.”

She explains that the zebrafish larvae are studied seven days after fertilisation in their bioassay. The larvae are incubated with the specific plant extract at a certain (non-toxic) concentration for three hours. Pentylenetetrazol (PTZ), a GABAA receptor antagonist that has been extensively used in rodent models for acute seizure and anxiety, is then administered to induce concentration-dependent seizures in the zebrafish larvae.

“GABA receptor antagonists are drugs that inhibit the action of gamma-aminobutyric acid, the chief inhibitory neurotransmitter in the mammalian central nervous system,” Prof Wilhelm says. “A specialised infrared camera is then used to track the movement of the larvae inside a chamber. The data is then converted into a graph which shows the movement of each larva over 30 minutes.

“If lowering of movement is observed at a specific concentration it means that the plant extract may have the potential to be used as an epileptic drug, since it has the ability to counteract the induced seizure in the larvae. This bioassay is extremely useful in drug discovery and toxicity screening of plant extracts.”

Zebrafish embryos, she says, develop quickly, with major organs forming within 36 hours of fertilisation. This rapid development allows researchers to observe the effects of experiments in a short period. The maintenance of a zebrafish model is less costly and labour-intensive than using a rodent model. “The use of zebrafish larvae allows for high-throughput screening due to their small size and transparency, which facilitates observation of CNS-related effects. Their genetic and physiological similarities to humans make them a valuable model for early-stage drug discovery.”

Potential uses

The next step in the research, according to Prof Wilhelm, is to identify a single compound from a natural source which may have potential anti-epileptic activity while causing less side effects than current drugs on the market. Researchers would then investigate the possibility of synthesising such a compound on a large scale, to eliminate the use of a natural resource and promote sustainability.

“Many plant extracts which I have screened show a synergistic effect in the zebrafish bioassay, meaning that the extract or the combination of compounds shows potential, but the isolated compounds are inactive. Even if a plant extract shows promise in preclinical and early clinical studies, obtaining regulatory approval for use as a treatment for epilepsy is a long and complex process.

“This includes demonstrating consistent efficacy, safety, and quality in large-scale clinical trials. One of the major challenges in using plant extracts is the lack of standardisation. The concentration of active compounds in plant extracts can vary depending on factors like the plant's growing conditions, harvest time, and extraction methods. This variability makes it difficult to ensure consistent efficacy and safety, therefore this is a time-consuming process.”

Green chemistry

After being approached by Dr Glen Taylor, Senior Director of the UFS Directorate Research Development (DRD), in 2017, regarding funding for Noldus Daniovision equipment, Prof Wilhelm received training from Prof Matthias Hamburger of the University of Basel in Switzerland on how to use such equipment. The larval zebrafish locomotive bioassay was established at the UFS Chemistry Department during 2017 and 2018 and now provides a third-stream income for the department, in conjunction with the Department of Genetics, where the adult zebrafish are housed.

Prof Wilhelm’s other research interests include green chemistry, food sustainability, and recycling. She is looking into green extraction techniques using non-conventional extraction methods to recover valuable bioactive compounds from agricultural and food residues. “Techniques like ultrasound, microwave-assisted extraction, and the use of deep eutectic solvents are becoming popular for their efficiency and alignment with circular economy principles.”

News Archive

Open letter from Prof Jonathan Jansen to all UFS students
2014-02-22

Dear Students of the University of the Free State

In the past four years there has emerged a new consensus on the three campuses of the University of the Free State (UFS) about the things that divide us – such as racism, sexism and homophobia. Students and campus leaders have worked hard to develop this new consensus in residences and in the open spaces on campus. There can be no doubt that new bonds of friendship have developed across the markers of race, ethnicity, class, religion and sexual orientation. I bear witness to these new solidarities every day on the campus.

You chose a white student to head up the transformation portfolio on the SRC. You chose a black captain to head up the university’s first team in rugby. You chose a white “prime” as head of residence to lead a predominantly black men’s residence. You chose a South African woman of Indian descent as Rag Queen and last week, a black student from Cape Town as the men’s Rag winner—choices not possible and never made before in our campus history. Many of you have intimate friends who come from different social or cultural or religious backgrounds. You learn together, share rooms together, pray together and party together. In other words, in the day to day workings of this university campus, you have demonstrated to campus, city and country that we can overcome the lingering effects of racism and other maladies in this new generation. You have helped create a university community inclusive of people of diverse religions, abilities, class and sexual orientation.

I have said this repeatedly that from time to time this new consensus will be tested – when a minority of students, and they are a small and dwindling minority, still act as if these are the days of apartheid. And when that consensus is tested as it was this week, and as it will be tested in the future, only then we will be able to assess the strength and durability of our progress in creating a new South African campus culture of human togetherness based on respect, dignity and embrace.

The real test of our leadership, including student leadership, is how we respond when our transformation drive is threatened.

Let me say this: I have absolute faith in you, as students of this great university, to stand together in your condemnation of these vile acts of violence and to move together in your determination to maintain the momentum for the Human Project of the University of the Free State. We have come too far to allow a few criminals to derail what you have built together in recent years.

There will, no doubt, be unscrupulous people on all sides of the political spectrum wanting to milk this tragedy for their own narrow purposes. There will be false information, rumours and exaggerations by those who wish to inflame a bad situation to gain mileage for their agendas. That is inevitable in a country that is still so divided.

I ask you, through all of this, to keep perspective. Two or ten or even twenty students behaving badly do not represent 30,000 students; a minority of violent and hateful persons do not represent the ideals, ambitions and commitments of the majority. At the same time, let us be realistic – anyone who thinks you can drive transformation without resistance clearly does not understand the difficult process of change.

The events of the week remind us, however, that we still have a long road to walk in deepening social and academic transformation at our university. Yes, we have invested hundreds of hours in training and mentorship; we have created new structures – such as the Institute for Reconciliation and Social Justice – to capture the energy and imagination of students driving transformation; we have created many opportunities for students to study and travel on this and other continents to enable cross-cultural learning; we have established formal and informal opportunities to dialogue about difficult issues on and off campus between students and their leaders; and we crafted new curricula to enable teaching and learning on the big questions of our times.

But this is clearly not enough, and so I have decided on the following immediate next steps:
  1. We will meet for several hours next week to think about how we can deepen the transformation of our university after this terrible incident.

  2. We will arrange a University Assembly on the events of the past week so that we speak with one voice on human wrongs and to re-commit to human rights and we will continue with open forum discussions during the months to come.

  3. We will review the entire spectrum of programmes, from orientation to residence life to the undergraduate curriculum, to determine how effective our interventions really are in reaching all students with respect to basic issues of human rights.

  4. We will review our media and communications strategy to determine how far and deep our messages on human rights travel across all sectors of the university community. In this regard it is important that the campus be blanketed on a regular basis with our condemnation of human wrongs and our commitment to human rights.

  5. We will commission the Institute for Reconciliation and Social Justice to review the events of the past week and make recommendations on how we can improve the campus environment so that all students are protected from harm inside residences, classrooms and in open spaces of the campus.

  6. We will take the questions raised during this week into the academic community and to the general staff of the university so that all personnel also engage with our own roles and responsibilities with respect to campus transformations.

  7. We undertake to make annual report-backs on transformation to all stakeholders in public forums so that students and staff and external communities can track the progress of the university on matters of human rights on campus.

I wish to thank my staff for acting firmly as soon as this tragic event came to our attention. We worked through the night to find and identify the perpetrators. We traced the two students and immediately handed them to the police. They were expelled. And throughout this process we offered counselling and support to the victim of this violent act.

The two former students were expelled and will now face justice in the criminal courts. It is hoped that in the course of time they will come to their senses and seek restoration and reconciliation with the student they so callously harmed. They are not part of the university community anymore.

That is the kind of university we are.

Jonathan D Jansen
Vice-Chancellor and Rector
University of the Free State
20 February 2014

 
Note: The use of the word ‘campus’ refers to all three campuses of the UFS, namely the Bloemfontein Campus, South Campus and Qwaqwa Campus.

 

We use cookies to make interactions with our websites and services easy and meaningful. To better understand how they are used, read more about the UFS cookie policy. By continuing to use this site you are giving us your consent to do this.

Accept