On Saturday 30 September 2017, the fifth group meeting was held involving patients belonging to the newly founded ‘Collagen VI Italia Onlus’, clinicians and researchers. The meeting, which took place at the Katia Bertasi Centre in Bologna, was characterised in the morning by speeches from researchers and clinicians working in the field of Collagen VI deficiency diseases and in close contact with patients, as well as from UILDM President Marco Rasconi and Anna Ambrosini, head of Telethon research programmes. In the afternoon, the first Members’ Meeting of the ‘Associazione Collagene VI Italia Onlus’ was held. Let us now take a detailed look at the medical-scientific topics that were discussed during the event.
The first to take the floor was Prof. Paolo Bernardi from the University of Padua, who addressed the issue of mitochondria in Collagen VI disorders. Mitochondria, the well-known ‘energy powerhouses’ of the cell, function poorly in Collagen VI deficiency; consequently, one of the possible therapeutic strategies consists precisely in acting pharmacologically on the mitochondria to block the progression of the pathology. Bernardi therefore explained how NIM811 is able to restore the efficiency of the mitochondria in the melanocytes (i.e. some of the cells found in the skin) of patients, which, although they are not muscle cells, reflect the mitochondrial defect. Bernardi also showed that the same drug also gives good results when administered to an animal model, the zebrafish, in which Collagen VI production is temporarily reduced to mimic Collagen VI deficiency disorders. Bernardi concluded his talk with the hope that NIM811 will be made available for the treatment of Collagen VI diseases as soon as possible.
The next person to speak was Dr Matilde Cescon, a researcher in Prof. Paolo Bonaldo’s laboratory at the University of Padua, who presented her most recent data on the function of Collagen VI in the ‘neuromuscular junctions’. These structures are located at the point of contact between nerves and skeletal muscles, and enable the brain’s order to move to be transformed into a tangible muscle contraction. In order to perform this function, nerves produce a small molecule called acetylcholine, and discharge it externally at the neuromuscular junctions, in a very narrow space known as the ‘synaptic cleft’. From here, acetylcholine can travel through a thin layer of extracellular matrix as far as the outer surface of muscle fibres. The arrival of acetylcholine at the surface of muscle fibres causes a rapid cascade of events that culminates in muscle contraction. Cescon reported her own recent discovery that Collagen VI is part of the extracellular matrix molecules present in the synaptic cleft, and she also described the neuromuscular junction defects she observed in model mice lacking Collagen VI. This finding is further supported by data Cescon obtained in collaboration with physicians by studying the neuromuscular junctions of patients with Collagen VI deficiency. This observation is extremely important, because it reveals for the first time a new aspect to be taken into account for the well-being of muscles in patients with Collagen VI diseases, thus providing new insights for potential therapies focused on the neuromuscular junction.
Next, Dr. Valentina Tonelotto, a doctoral student in Prof. Bonaldo’s laboratory, introduced the work hitherto carried out to generate a new animal model for pathologies due to Collagen VI deficiency by totally and permanently deactivating the production of this protein in zebrafish. This animal has innumerable advantages for studying the effects of Collagen VI deficiency on the organism during embryonic development, as fertilisation normally takes place in the external environment and the larvae are completely transparent. The adoption of zebrafish as a model for genetic disorders is becoming increasingly common in the world’s scientific community, due to the ease of conducting experimentation and the minimally invasive nature of the experiments. First and foremost, Tonelotto is seeking to understand in which organs and tissues of the zebrafish Collagen VI is found, to understand where it plays a key role in maintaining proper function. In addition, zebrafish without Collagen VI have been generated within the lab, exploiting a ‘molecular scissors’ system called CRISPR-Cas9 that allows them to specifically cut the piece of DNA that provides instructions for building Collagen VI. Early data indicate that these fish display defects in both muscle and cartilage, and studies are underway to investigate which fish organs and intracellular processes are defective in the absence of Collagen VI. These studies will therefore shed new light on the molecular mechanisms underlying Collagen VI diseases, providing a new animal model for testing possible therapies, and thus represent a breakthrough towards their understanding and treatment.
Researcher Dr. Manuela Antoniel, who works together with Dr. Patrizia Sabatelli at the Istituto Ortopedico Rizzoli in Bologna, then took the floor to describe the latest results of the project financed within the framework of the international ‘Collagen VI Alliance’ programme underway in Bologna. In particular, Antoniel described the low-invasive cellular models that are being studied to ascertain whether they are suitable for the diagnosis and study of Collagen VI pathologies, which in the future will lessen the need for painful muscle biopsies for patients. These models are: melanocytes obtained from skin biopsies, which mirror many characteristics presented by muscle cells lacking Collagen VI, such as the mitochondrial defect, and stem cells obtainable from urine. The latter in particular are very interesting due to their easy availability and the possibility of being grown in culture, and will be more closely investigated in the future. Sabatelli and Antoniel also invited interested members of the audience to contribute by providing a urine sample, so as to enable them to continue collecting data for this exciting project.
Drs. Silvia Castagnaro and Ilaria Gregorio, respectively a post-doc and a doctoral student in Prof. Bonaldo’s group, did not discuss scientific data in their speech, but rather sought to answer a question that those present have often asked themselves, namely ‘what does it mean to conduct research? Castagnaro explained how a research group is structured, from PhD students to researchers; what publications are and how important they are for a group to obtain funding in order to work and be able to pay for the reagents, services and instruments needed to do research. Next, they presented the most recent projects devised by the Bonaldo team, aimed at finding new therapies for Collagen VI disorders. The first aims to understand precisely which ‘portions’ of Collagen VI mediate its various functions (e.g. induction of autophagy). Once this is understood, the idea is to produce ‘healthy’ Collagen VI fragments that replace the mutated portions of the molecule in the cells of patients with Collagen VI disorders. In this way, it will be possible in the future to carry out quasi-personalised clinical trials, in which mutations can be compensated for in a targeted manner. Another project concerns the use of spermidine, which in Collagen VI-deficient mice is able not only to induce autophagy in muscles, but also to improve the condition of the mitochondria. However, the mechanism of action of spermidine is not yet known. This project therefore aims to find out which mechanisms allow spermidine to induce autophagy using different models, such as zebrafish and cultured cells. Once this has been determined, non-invasive methods would then be found to assess the induction of autophagy in model animals, e.g. by taking blood samples. In this way, it would therefore be possible, even in patients, to assess the autophagic state following treatment with spermidine in a safe, continuous and pain-free manner.
Another important aspect was addressed by Dr Andrea Fabiani, who introduced the problem of pneumothorax. First of all, Fabiani explained exactly what it involves: our lungs are very elastic organs that must be kept expanded, otherwise they would be unable to let air pass through them. For this reason, the lungs are ‘glued’ to the inner walls of the ribcage by membranes, called ‘pleuras’. If, for some reason, such as trauma, the pleurae become dislodged from the ribcage, the lung loses its ability to remain expanded, and collapses on itself, due to its elastic nature. This event is called pneumothorax, and in this condition the patient is unable to breathe properly. Fabiani recalled that this condition is extremely dangerous and, if underestimated, can even be fatal. However, he recalled that the diagnosis of pneumothorax is easy to establish, and that the therapy simply consists in sucking out the gas and restoring the function of the pleurae.
As Collagen VI diseases may indeed be more susceptible to pneumothorax, Fabiani urged those present to inform him of any cases of pneumothorax not yet reported in the medical literature, as they might highlight an important manifestation of the disease that has so far remained unknown. Not only that: if patients with Collagen VI disease are at greater risk of suffering from a pneumothorax attack, it means that this problem must imperatively be taken into account, e.g. in the case of surgery or even minor accidents. This aspect was also emphasised by anaesthetist Dr. Mariada Perrone, who reiterated the importance of correct information for doctors and anaesthetists dealing with patients with these diseases, in order to prevent unexpected and unpleasant complications in the operating theatre.