Hepatic Insulin Resistance in Hyperthyroid Rat Liver : Vitamin E Supplementation Highlights a Possible Role of ROS

Thyroid hormones are normally involved in glycaemic control, but their excess can lead to altered glucose metabolism and insulin resistance (IR). Since hyperthyroidism-linked increase in ROS results in tissue oxidative stress that is considered a hallmark of conditions leading to IR, it is conceivable a role of ROS in the onset of IR in hyperthyroidism. To verify this hypothesis, we evaluated the effects of vitamin E on thyroid hormone-induced oxidative damage, insulin resistance, and on gene expression of key molecules involved in IR in the rat liver. The factors involved in oxidative damage, namely the total content of ROS, the mitochondrial production of ROS, the activity of antioxidant enzymes, the in vitro susceptibility to oxidative stress, have been correlated to insulin resistance indices, such as insulin activation of hepatic Akt and plasma level of glucose, insulin and HOMA index. Our results indicate that increased levels of oxidative damage ROS content and production and susceptibility to oxidative damage, parallel increased fasting plasma level of glucose and insulin, reduced activation of Akt and increased activation of JNK. This last result suggests a role for JNK in the insulin resistance induced by hyperthyroidism. Furthermore, the variation of the genes Pparg, Ppara, Cd36 and Slc2a2 could explain, at least in part, the observed metabolic phenotypes.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:11

Enthalten in:

Antioxidants (Basel, Switzerland) - 11(2022), 7 vom: 29. Juni

Sprache:

Englisch

Beteiligte Personen:

Fasciolo, Gianluca [VerfasserIn]
Napolitano, Gaetana [VerfasserIn]
Aprile, Marianna [VerfasserIn]
Cataldi, Simona [VerfasserIn]
Costa, Valerio [VerfasserIn]
Ciccodicola, Alfredo [VerfasserIn]
Di Meo, Sergio [VerfasserIn]
Venditti, Paola [VerfasserIn]

Links:

Volltext

Themen:

Akt
Antioxidant enzymes
Cd36
HOMA index
Ilb
Irs2
JNK
Journal Article
Oxidative damage
Ppara
Pparg
ROS production
Slc2a1
Slc2a2

Anmerkungen:

Date Revised 31.07.2022

published: Electronic

Citation Status PubMed-not-MEDLINE

doi:

10.3390/antiox11071295

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM344035778