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In 2023, UNamur opened a fourth CaNDLE call funded through the joint support of the Fonds Jérôme pour le développement durable and the Assemblée des Cercles of UNamur students. Discover one of the 7 selected projects.

Summary: Impact of the UPR pathway on the establishment of the UVB-induced senescent phenotype Skin aging, influenced by a combination of intrinsic and extrinsic factors, leads to damage capable of altering skin functions. Among extrinsic factors, ultraviolet (UV) radiation is responsible for skin photoaging. In particular, these elements lead to an accumulation of senescent cells capable of contributing to the development of age-related pathologies such as skin cancers. Indeed, senescence is accompanied by profound morphological and molecular changes within the cell. This includes a modification of its secretome, which becomes enriched with pro-inflammatory cytokines, growth factors and extracellular matrix remodeling enzymes, altering the characteristics of tissues as they age. Nevertheless, the precise mechanisms leading to the senescent phenotype induced by UVB remain largely unknown. In this context, the main objective of this work was to identify molecular mechanisms underlying the establishment of UVB-induced senescence in normal human dermal fibroblasts (NHDFs), mechanisms that could contribute to skin aging. In vitro, we confirmed that repeated UVB exposures induce premature senescence in NHDFs and that this state is associated with activation of the three branches of the UPR (Unfolded Protein Response) pathway responsible for maintaining homeostasis of the endoplasmic reticulum (ER), the primary secretory compartment. These observations were supported by transcriptomic analysis, revealing regulatory elements linked to major senescence pathways and ER functions in UVB-exposed NHDFs. Subsequently, we showed that the ATF6α branch plays a central role in the occurrence of biomarkers of the UVB-induced senescent phenotype. Indeed, ATF6α invalidation not only protects against UVB-induced morphological changes, but reduces the percentage of SA-βgalactosidase (SA-βgal)-positive cells, prevents persistent DNA damage, and alters the expression of major factors of the senescence-associated secretory phenotype (SASP). As SASP exerts, among other things, a pro-tumoral action, we sought to assess whether the conditioned medium (CM) of UVB-exposed fibroblasts invalidated for ATF6α could impact the migration and invasion potential of melanoma-derived cells. However, we did not observe any ATF6α-dependent pro-migratory or pro-invasive effects.To highlight a potential role for ATF6α in another biological process, we exploited our transcriptomic and secretomic analyses and identified a possible effect of ATF6α on the paracrine control of the skin environment. To explore this, we focused on SASP factors (cytokines and metalloproteases) regulated by ATF6α and whose impact on the tissue environment was known. Next, we treated a reconstructed human epidermis (RHE) model with MC derived from NHDFs exposed to UVB or not, and invalidated or not for ATF6α. Surprisingly, we observed that MC from UVB-exposed NHDFs increased RHE thickness and basal keratinocyte proliferation, via an ATF6α-dependent mechanism. Finally, we identified IL8 as a major paracrine factor involved in this process, since IL-8 blockade by neutralizing antibodies prevents excessive keratinocyte proliferation. In conclusion, we report the role of ATF6α in UVB-induced senescence as well as its impact on the preservation of skin homeostasis under stress conditions notably through the regulation of the expression of SASP components. This suggests that ATF6α and its effectors could be promising targets controlling the effects of skin aging.Abstract: Impact of the UPR pathway on the establishment of the senescent phenotype induced by UVBSkin aging, influenced by a combination of intrinsic and extrinsic factors, can result in damage that has the potential to alter skin functions. Among extrinsic factors, ultraviolet (UV) radiation is responsible for skin photoaging. These factors notably contribute to the accumulation of senescent cells which in turn can contribute to the development of age-related pathologies, including skin cancers. Indeed, senescence is characterized by profound morphological and molecular changes within the cell. This includes a modification of its secretome, which becomes enriched in pro-inflammatory cytokines, growth factors, and matrix-remodeling enzymes, altering tissue characteristics during aging. However, the exact mechanisms driving the senescent phenotype induced by UVB remain largely unknown. In this context, the main objective of this work was to identify the underlying molecular mechanisms responsible for the establishment of UVB-induced senescence in normal human dermal fibroblasts (NHDFs), mechanisms that may play a role in skin aging. In vitro, we confirmed that repeated exposures to UVB induce premature senescence of NHDFs and that this state is associated with the activation of the three branches of the Unfolded Protein Response (UPR), which are responsible for maintaining endoplasmic reticulum (ER) homeostasis, the primary cellular secretion compartment. These observations were supported by transcriptomic analysis, revealing regulatory elements related to major senescence pathways and ER functions in UVB-exposed NHDFs. Subsequently, we demonstrated that the ATF6α branch plays a central role in the development of the UVB-induced senescent phenotype. Indeed, the silencing of ATF6α not only protects against morphological changes induced by UVB, but also reduces the percentage of senescence-associated β-galactosidase (SA-βgal) positive cells, prevents the persistence of DNA damage, and alters the expression of major factors associated with the senescence-associated secretory phenotype (SASP).The SASP, exerting a pro-tumoral action, led us to assess whether the conditioned medium (CM) from UVB-exposed fibroblasts invalidated for ATF6α could impact the migration and invasion potential of melanoma cells. However, we did not observe any ATF6α-dependent pro-migratory or pro-invasive effects. To highlight a potential role of ATF6α in another biological process, we further analyzed our transcriptomic and secretomic analyses and identified a possible effect of ATF6α on the paracrine control of the skin environment. To explore this, we focused on SASP factors (cytokines and metalloproteinases) regulated by ATF6α and whose impact on tissue environment was known. Subsequently, we treated a reconstructed human epidermis (RHE) model with CM from NHDFs exposed or not to UVB and invalidated or not for ATF6α. Surprisingly, we observed that the CM from UVB-exposed NHDFs increased the thickness of the RHE as well as the proliferation of basal keratinocytes, via an ATF6α-dependent mechanism. Finally, we identified IL8 as a major paracrine factor involved in this process, as blocking IL-8 with neutralizing antibodies prevented excessive proliferation of keratinocytes. In conclusion, we report the role of ATF6α in UVB-induced senescence and its impact on the preservation of skin homeostasis under stress conditions, particularly through the regulation of the expression of SASP components. This suggests that ATF6α and its effectors could be promising targets for controlling the effects of skin aging. Jury Prof. Yves POUMAY (Department of Medicine, UNamur), chairmanProf. Florence CHAINIAUX (Department of Biology, UNamur), promoter and secretaryProf. Olivier PLUQUET (Canther, University of Lille), co-promoterProf. Isabelle PETROPULOS (Adaptation Biologique et Vieillissement, Sorbonne Université)Prof. Jérôme LAMARTINE (Laboratoire de Biologie Tissulaire et d'Ingénierie thérapeutique, Université Claude Bernard Lyon 1)Prof. Fabienne FOUFELLE (Maladies métaboliques, diabète et comorbidités, Sorbonne Université)

What environmental impact can a contraceptive molecule have? Recent work by Professor Patrick Kestemont, Director of UNamur's Environmental and Evolutionary Biology Research Unit (URBE) and his team answers this question, and has just been published in the journal Environment International. The article's lead author is Sébastien Baekelandt, postdoctoral researcher at URBE.

Students enrolled in the Faculty of Science have the opportunity to go abroad during their studies, either as part of their course or as part of an internship!Each year, we also welcome several foreign students who enroll in a course at the University of Namur, or who join us for a semester or a year of study.

The staff of the Faculty of Science includes a quarter of researchers, assistants, post-docs and international professors. Through their experience and culture, they enrich teaching, research and the life of the faculty and the institution.

On this page you will find the various people to contact within the Faculty of Science.

The Department of Physics is structured into entities in charge of its organization, teaching and research.

In a new publication, the European Reference Genome Atlas (ERGA) announces the success of its pilot project. This pioneering initiative has brought together a vast collaborative network of researchers and institutions in 33 countries to produce high-quality reference genomes of 98 European species. This continental effort paves the way for a new, inclusive and equitable model of biodiversity genomics.

A 3rd-year veterinary medicine student with a passion for drawing, Élise Hottois has transformed one of the walls of the Faculty of Science into a veritable work of art.

Michaël Lobet, professor in the Department of Physics, and André Fuzfa, astrophysicist and professor in the Department of Mathematics at UNamur, have just been awarded a grant from the Wernaers Fund to develop an original scientific project: the design of a comic strip that will explore all the fascinating facets of energy. Aimed at a "student" audience, it will weave the link between science and science fiction, and will be produced thanks to the invaluable pencil strokes of illustrator Jean-Marc Dubois.

September 15, 2025 A program for all09h00 | Welcome at Pedro Arrupe (Rue de Bruxelles, 67 - 5000 Namur).11h00 | Back-to-school celebration at Saint-Aubain Cathedral (Place Saint-Aubain - 5000 Namur) then welcome students by the Cercles. Home of the Faculty of Science September 16, 2025From 8:30 to 9:30 a.m.: welcome by the Dean and Vice-Dean of the Faculty of Sciences in S01 for Block 1 VT and BioFrom 10:00 to 11:00 a.m.: welcome by the Dean and Vice-Dean of the Faculty of Sciences in S01 for Block 1 Math, Phys, Chemistry, Geo²Then: welcome in each department of the faculty. Home by department September 16After the Faculty welcome, you will be allocated according to your department: DepartmentSchedule and roomMathematicsto be confirmedPhysicsto be confirmedChemistryto be confirmedGeography and geologyto be confirmedBiologyto be confirmedVeterinary medicineto be confirmedClick on this link to get all the information about your academic start at UNamur. You need your login (eid) and associated mdp to access it. And before school starts? In addition to the cpreparatory courses scheduled between mid-August and early September, the University of Namur offers first-time students the opportunity to discover their Faculty as well as the campus, and to take part in a services forum during 2 integration days.Exclusively aimed at students completing their secondary education (newcomers), these preparatory courses are tailored to each university program.Put all the assets on your side!Preparatory courses for students in the Faculty of ScienceMathematics and Physics: August 25 to September 5, 2025Biology, Chemistry, Geography, Geology and Veterinary Medicine: August 18 to 29, 2025Find out more about the schedules for the various sessions and register for the preparatory courses... NEW! To help you make the most of your first year at the University, take part in our integration days!Friday afternoon, September 12 - reserved for newcomers, free, registration requiredTour of your Faculty and campus (integrated into the preparatory courses if you are enrolled)Barbecue and evening party You must register for both activities, even if you are enrolled in the preparatory courses! The registration link will be available soon.Saturday, September 13, 10am-4pm - open to all - free, open accessServices forum: presentation of student services (sports, culture, commitment, social cell, ...), project kots and activities organized on campus...