No public access
master's thesis
Effects of tyrosol and quercetin on indicators of ageing in period circadian mutants of Drosophila

Franka Rigo (2016)
Sveučilište u Rijeci
Odjel za biotehnologiju
Metadata
TitleUtjecaj tirosola i kvercetina na indikatore starenja i redoks statusa u period cirkadijalnih mutanata Drosophile
AuthorFranka Rigo
Mentor(s)Rozi Andretić Waldowski (thesis advisor)
Abstract
Ciklusi svjetla i mraka reguliraju cirkadijalne gene koji diktiraju ritmove metabolizma i antioksidativnih enzima koji su usko povezani sa stvaranjem slobodnih radikala (ROS) u organizmu. Prema jednoj od teorija starenja, nakupljanje slobodnih radikala uzrokuje smanjenje funkcionalnog kapaciteta organizma, što je vidljivo na bihevioralnoj (smanjenje lokomotorne aktivnosti, poremećeno spavanje) i biokemijskoj razini (oštećenja proteina, DNA i lipida). Poznato je da su mutacije u period (per) cirkadijalnom genu povezane s prijevremenim starenjem. Polifenoli su poznati po svojim antioksidativnim svojstvima, što znači da smanjuju i usporavaju oksidativna oštećenja stanica izazvana slobodnim radikalima. Istraţili smo potencijalan blagotvorni učinak polifenola kvercetina i tirosola na indikatore starenja kod period cirkadijalnih mutanata (per01) Drosophile melanogaster. Testovi su provedeni na per01 mutantima Drosophile oba spola. Mušice su od roĎenja hranjene hranom s dodatkom različitih koncentracija kvercetina ili tirosola. Testirali smo njihov bihevioralni i biokemijski fenotip nakon 2, 4 i 6 tjedana tretmana polifenolima te smo rezultate usporedili s mladim i starim netretiranim mušicama. Od bihevioralnih indikatora starenja mjerili smo negativnu geotaksiju (sposobnost vertikalnog penjanja), količinu lokomotorne aktivnosti i spavanja tijekom 24 sata, otpornost na stres izgladnjivanjem i isušivanjem, preţivljenje i teţinu. Mjerili smo i biokemijske indikatore u koje spadaju aktivnost antioksidativnih enzima katalaze (CAT) i superoksid dismutaze (SOD), nakupljanje AGE biomarkera starenja te količina mono-di-triglicerida i reduktivnih šećera. Rezultate testova na per01 mutantima usporedili smo s rezultatima mušica divljeg tipa. Potvrdili smo da postoje razlike u procesu starenja mušica divljeg tipa i period mutanata. Polifenoli kvercetin i tirosol pozitivno su djelovali na neke od bihevioralnih i biokemijskih indikatora starenja, a taj učinak ovisio je o spolu, genotipu i starosti mušica, te koncentraciji polifenola. Točan mehanizam djelovanja polifenola nije još razjašnjen, a postoji mogućnost da na smanjenje oksidativnog stresa djeluje direktno (uklanjanjem ROS ili čak sprječavanjem njihova nastajanja) i indirektno (potičući djelovanje endogenih antioksidativnih enzima). Vaţno otkriće ovog istraţivanja je postojanje interakcije per gena s mehanizmom djelovanja polifenola.
Keywordsageing ROS per gene polyphenols Drosophila melanogaster
Parallel title (English)Effects of tyrosol and quercetin on indicators of ageing in period circadian mutants of Drosophila
Committee MembersRozi Andretić Waldowski (committee chairperson)
Igor Jurak (committee member)
Ivana Ratkaj (committee member)
GranterSveučilište u Rijeci
Lower level organizational unitsOdjel za biotehnologiju
PlaceRijeka
StateCroatia
Scientific field, discipline, subdisciplineBIOTECHNICAL SCIENCES
Biotechnology
Study programme typeuniversity
Study levelgraduate
Study programmeBiotechnology in medicine
Academic title abbreviationmag. biotech. in med.
Genremaster's thesis
Language Croatian
Defense date2016-10-21
Parallel abstract (English)
Circadian genes regulate metabolic changes closely connected with ageing. Ageing is caused by accumulation of Reactive Oxidative Species (ROS) which leads to changes in behaviour (decrease in locomotor activity, disrupted sleep) and physiology (damaged proteins, DNA and lipides). It was reported that mutation in period (per) circadian gene influences ageing by shortening lifespan. Polyphenols quercetin and tyrosol are known antioxidants, so we tested their beneficial effect on indicators of ageing and redox state in per01 circadian mutant. Tests were performed on flies of both sexes. They were fed on food containing different concentrations of polyphenols from eclosion and compared to flies fed on regular food. We tested their behavioral and biochemical phenotypes after 2, 4 and 6 weeks of treatment. We measured negative geotaxis (vertical climbing ability), amount of locomotor activity and sleep during 24 h, resistance to starvation and dehydration stress, longevity and weight. We also measured biochemical phenotypes such as CAT (catalase) and SOD (superoxide dismutase) activity, AGE biomarker, amount of reductive sugars and mono-di-tri-glycerides. We confirm difference in ageing process of wt and per01 flies. Polyphenols quercetin and tyrosol had positive effect on several behavioral and biochemical indicators of ageing. This effect was dependent on sex, genotype and age of flies and concentration of polyphenols. Exact mechanism of action of polyphenols is still not clear, and they could act directly (by removing ROS or preventing its generation) and indirectly (by stimulating the activity of the endogenous antioxidative enzymes). An important finding of this work is the interaction between per circadian gene and the mechanism of action of polyphenols.
Parallel keywords (Croatian)starenje ROS per gen polifenoli Drosophila melanogaster
Resource typetext
Access conditionNo public access
Terms of usehttp://rightsstatements.org/vocab/InC/1.0/
URN:NBNhttps://urn.nsk.hr/urn:nbn:hr:193:952414
CommitterLea Lazzarich