AGH UST scholars investigate how drugs change brain chemistry

We are talking with Professor Piotr Suder, AGH UST Professor Anna Bodzoń-Kułakowska, and Dr hab. Anna Drabik sitting in one of the rooms of the AGH UST Biochemistry Research Group. We are watching numerous picture frames hung on the walls that document international contacts of the Krakow scientists. One draws particular attention – a photo taken at the peak of the Etna volcano. This is a keepsake from a cooperation with Professor Giuseppe Grasso from the University of Catania, with whom the AGH UST employees have jointly published a book titled Mass Spectrometry: An Applied Approach. Successful collaborations do not end with this one; on the contrary, the group has considerably more to boast about.

The history of the Group’s activity, which is now part of the Department of Analytical Chemistry and Biochemistry at the Faculty of Materials Science and Ceramics, dates back to the year 2009. In reality, however, it has been going on even longer than that, as the original team of researchers had previously worked at the Jagiellonian University Faculty of Chemistry. At that time, the leader of the group was Professor Jerzy Silberring, who was formerly associated with the Karolinska Institutet. His supervisor there was Professor Lars Terenius, a world-renowned scientist famous for discovering naturally produced peptides that act on the brain's opiate receptors in a manner similar to that of other opiates. This discovery helped elucidate the pharmacological effects of opiates and other opioid-derived painkillers. ‘The chemical system of the brain has always been at the centre of our research interests’, recollects Professor Suder, reminiscing about his time at the JU.

From substance abuse treatment to new pain relievers

Although this is not the only research area that the scientists are preoccupied with at the moment, they are still trying to pursue their past interests. Therefore, they are focusing on the aforementioned opioids, as well as other psychoactive substances. They want to find out how they affect the biochemical processes that occur in the brain of a person who uses them. Their investigations might help doctors in the future. Opiates, such as morphine, have been used by people for ages for a variety of reasons: from ancient rituals and therapies to psychedelic effects. They are also widely used in pain management. However, prolonged use could result in the development of drug tolerance, which requires the need to administer gradually larger doses to achieve the desired effect. Furthermore, this can result in dependence and addiction of the organism. ‘We want to understand why this is happening and perhaps find ways of administering painkillers without the risk of developing addiction or drug tolerance’, says Professor Bodzoń-Kułakowska.

Dr Drabik adds the necessity of helping those already hooked on drugs, such as heroin, which is also an opioid. The AGH UST researcher points to yet another important aspect of the investigation: ‘Currently, we’re walking away from synthetic drugs and turning to substances produced naturally by the human body, which can modulate brain activity. We are investigating ways of administering them to prevent various types of afflictions’.

Professor Suder explains that by looking at the biochemical reaction of the brain on administering opioids, we must take into account the complex network of interconnected neurotransmitters and neuromodulators, which play a vital role in the processes occurring in the limbic system. In addition, there are several factors at play that influence gene activity after prolonged exposure of the organism to psychoactive substances, even after cessation of use.

‘Science has become well acquainted with the basic mechanisms of opioid activity and its receptors, and it can describe the chemical response of the central nervous system at a fundamental level. However, the totality of processes occurring in the reward system is so complicated that we, in fact, know very little about it. Therefore, research teams around the world, including us, investigate the problem of addiction’, the researcher explains.

Studying proteins, lipids, and peptides

The development of science means taking tiny steps that gradually expand the available knowledge. By placing one foot in front of the other, the AGH UST employees apply proteomics to investigate the change in protein concentration in brain tissue. In analysing a selection of proteins, for example enzymes produced by particular structures of the central nervous system, which are involved in metabolic processes in cells, they showed that morphine can disrupt energy conversion pathways, which is a starting point for further research.

‘If we were able to pinpoint a pathway that has stopped working properly due to drug addiction and if we were able to modify it and return its normal functioning, it could be possible that we would have discovered a promising substance that counteracts drug addiction or impedes abstinence symptoms’, explains Professor Bodzoń-Kułakowska.

Surprisingly, the scientists have found that morphine, amphetamine, and cocaine change the concentration of lipids in the brain – to date, lipids have not been commonly associated with the process of addiction to psychoactive substances. ‘We published our article around the time US scientists published theirs and they have written a very similar article. However, there was no controversy about priority, as both teams have conducted their research unbeknownst to the fact that someone has been working on the same problem at the same time. This was quite an interesting literary phenomenon’, Professor Suder says.

Electrospray ionisation for the Exploris 240 spectrometer with the Ultimate 3000 chromatograph, photo by Marianna Cielecka

The AGH UST researchers have also presented a novel approach to mass spectrometry tissue imaging (MALDI-MSI), which allows one to detect cholesterol and lipids in brain tissue with greater precision than ever. Recent research focused on hemorphins, naturally occurring endogenous opioid peptides, and their role in the alcohol addiction process. ‘Administering hemorphins could have therapeutic application. Furthermore, it has also shown analgesic effects’, Dr Drabik says.

Animals in research: what distinguishes a human brain from a rat brain?

In their studies, Krakow scientists have examined rats instead of people. The animals were initially administered psychoactive substances and subsequently their brains were studied. The experiments have been conducted in accordance with Polish and European laws and have been approved by the appropriate Bioethics Committee. In designing research involving animals, scientists strictly observe the so-called “3R” principle (refinement, reduction, replacement). It offers recommendations that urge scientists to design their investigations accordingly to reduce animal stress and suffering (refinement). Moreover, it forces them to reduce the number of animals used in an experiment to the absolute minimum (reduction) and, if possible, replace animal research with other available methods (replacement).

We asked therefore why research with animals has no alternatives and to what extent the findings based on rat organ examination could be transferrable to people.

‘The rat model perfectly mirrors what is going on in the human brain on a chemical level’, explains Professor Suder. ‘Hence, we can study the changes after administering drugs or other addictive substances and infer the consequences of the same action on the human brain. Truth be told, there are other models as well, which can show us the things we’re after, although to a limited extent. For instance, we can grow cell lines or use computer modelling to study individual receptors in the context of the effects of particular substances. This, however, does not provide us with complete knowledge of the process under investigation. Some tests cannot be conducted differently than by observing the way the studied animal behaves under strictly controlled experimental conditions’.

Dewar flask used to store collected tissue samples, photo by Marianna Cielecka

Dr Drabik explains that scientists are doing everything in their power to make sure that “no single animal life has been lost in vain”: ‘We don’t only harvest the brain, but also other organs. All harvested tissue samples are stored in Dewar flasks and used for other projects. The whole biological material obtained is stored in a biobank and is thoroughly labelled in case there’s a need to repeat particular analyses. A similar situation is with material harvested from humans, which is stored according to proper procedures and meticulous labelling, together with an anonymised medical history of the donor.

Drugs in science

Scientists who want to legally purchase psychoactive substances must obtain the approval of the Chief Pharmaceutical Inspectorate. However, direct oversight of the laboratory rests with the Provincial Pharmaceutical Inspectorate. The acquired substances are stored and subsequently disposed of under strictly determined procedures. Failure to observe them might have severe consequences from the state regulators.

‘Intoxicants and psychedelics can be purchased in small quantities, usually grams, according to the approval, which states the exact quantity of a given substance. In experiments, we have to use pure substances, because otherwise the results of our analyses won’t be coherent, for instance, with those of other research teams. The pure substances used in our analyses are nowhere near the things you find in the streets due to the production control, purification, and delivery method. Therefore, they’re extremely expensive; we pay thousands just for one gram’, the team leader says.

Is this an adequate price to pay for scientific progress?

‘We are constantly perfecting our research methods. The technology we have at our disposal becomes more and more sensitive. Currently, we are able to observe processes that could not be examined just a few years ago’, claims Professor Bodzoń-Kułakowska. ‘We hope that eventually our research will improve the lives of addicted people and their loved ones in social and economic contexts’.

 

Piotr Włodarczyk, Centre for Communication and Marketing