Vpliv kalorične restrikcije na heterogenost odzivov celic beta trebušne slinavke v mišjem modelu sladkorne bolezni tipa 2

Fras, Katarina Barbara (author), Kreft, Marko (mentor), Skelin Klemen, Maša (comentor)

Preučili smo učinke kalorične restrikcije na funkcijo celic beta trebušne slinavke miši, linije C57Bl/6J. S pomočjo konfokalne mikroskopije smo na svežih tkivnih rezinah pankreasa miši, spremljali začetke in konce oscilacij [Ca2+]i v celicah beta, po stimulaciji z glukozo (7 mM, 8 mM, 9 mM, 10 mM, 12 mM, 16 mM, 22 mM). Snemanje oscilacij [Ca2+]i je potekalo na treh skupinah miši, ki so se razlikovale glede na tip diete (zahodna dieta – WD skupina/nizkokalorična dieta – RCD skupina/kontrolna dieta – CD skupina). Pri kontrolni skupini miši smo ugotovili glukozno odvisnost začetkov in koncev oscilacij [Ca2+]i - z naraščanjem stimulatorne koncentracije glukoze so se časovni zamiki do odziva krajšali, časovni zamiki do izklopa pa daljšali. Pri skupini samcev je dieta WD vplivala na krajše aktivacijske čase in bolj heterogene odzive celic beta. Časovni zamiki do odziva pri skupini RCD samcev so bili pri določenih stimulatornih koncentracijah glukoze podobni zamikom kontrolne skupine. To kaže na izboljšanje metabolne aktivnosti celic beta. V nekaterih primerih pa se je pri skupini RCD samcev še vedno kazal vpliv predhodnega hranjenja z WD. Pri samicah nismo ugotovili vpliva WD na začetke oscilacij [Ca2+]i. Posledično nismo mogli govoriti o vplivu RCD pri tej skupini. Konci oscilacij [Ca2+]i so bili zaradi WD spremenjeni tako pri samcih kot pri samicah. To se je kazalo v daljših časovnih zamikih do izklopa in v večji heterogenosti odzivov v celicah beta. Dieta RCD je pri nekaterih stimulatornih koncentracijah vplivala na izboljšanje dinamike oscilacij [Ca2+]i, ki je bila prizadeta zaradi učinkov WD.

• Language: Slovenian
• Keywords: biologija, sladkorna bolezen tipa 2, restrikcijska dieta, zahodna dieta, oscilacije kalcija, trebušna slinavka, Langerhansovi otočki, celice beta
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: BF - Biotechnical Faculty
• Place of publishing: Ljubljana
• Publisher: [K. B. Fras]
• Year: 2022
• PID: 20.500.12556/RUL-136236
• UDC: 57
• COBISS.SI-ID: 111959043
• Publication date in RUL: 21.04.2022

FRAS, Katarina Barbara, 2022, Vpliv kalorične restrikcije na heterogenost odzivov celic beta trebušne slinavke v mišjem modelu sladkorne bolezni tipa 2 [online]. Master’s thesis. Ljubljana : K. B. Fras. [Accessed 18 April 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=136236

Secondary language

• Language: English
• Title: The influence of caloric restriction on response heterogeneity in pancreatic ß-cells of a mouse model with type II diabetes

Abstract

We investigated the effects of caloric restriction on pancreatic beta cell function. The mouse strain C57Bl/6J was used for the experiments. Acute tissue sections of pancreas were stimulated with glucose solutions (7 mM, 8 mM, 9 mM, 10 mM, 12 mM, 16 mM, 22 mM) and observed with a confocal microscope to measure the time course of activation and deactivation of beta cell oscillatory calcium activity. Three groups of mice differing in diets (Western diet - group WD /restrictive caloric diet - group RCD /control diet - group CD ) were involved in [Ca2+]i imaging in living cells. The beta cell activation and deactivation times in the healthy control group were glucose dependent. The time delay to activation shortened with increasing glucose concentration, as did the heterogeneity of responses. With increasing glucose concentration, delays to deactivation became longer and heterogeneity increased. The WD shortened activation time in beta cells of male mice. In contrast, the RCD improved the metabolic activity of beta cells of male mice in some cases, as the activation delays were similar to those of the control group. But at a certain glucose concentration, the effects of the WD were still present. In the female mice group, there were no significant effects of the WD on the activation delays, therefore, the effects of the RCD could not be observed. Because of the WD, beta cells, in the male and female WD groups, deactivated later and more heterogeneously than in the control group. At some glucose concentrations, the ends of oscillation in the male and female RCD groups were similar to those in the control group, but in some cases the effects of the WD were still present.

• Keywords: biology, diabetes type 2, restricted calorie diet, western diet, calcium oscillations, pancreas, islets of Langerhans, beta cells