RESULTS: Compared to the non-obese diabetic resistant (NOR) mice, the peritoneal macrophages of NOD mice expressed increased levels of PPARalpha but reduced levels of PPARgamma2, while PPARgamma1 expression was unchanged in all age groups. CD4-positive lymphocytes expressed low levels of PPARalpha in diabetic NOD mice and greatly reduced expression of PPARgamma2 in all age groups. Unlike peritoneal macrophages and CD4-positive cells, the CD8-positive cells expressed low levels of PPARgamma1 in diabetic NOD mice but no difference in PPARalpha and PPARgamma2 expression was observed compared to NOR mice.
CONCLUSION: The current findings may suggest an important regulatory role of PPARs in the pathogenesis of autoimmune diabetes.
METHODS: In vitro cell model of IDD was established by treating human nucleus pulposus cells (HNPCs) with interleukin-1β (IL-1β). The level of peroxisome proliferator-activated receptor γ (PPARγ) was examined in the IDD cell model by Western blot and quantification real-time reverse transcription-polymerase chain reaction (qRT-PCR). The expression level of miR-96-5p was detected by RT-qPCR. Effects of PPARγ or/and PPARγ agonist on inflammatory factors, extracellular matrix (ECM), apoptosis, and nuclear factor-kappaB (NF-κB) nuclear translocation were examined through enzyme-linked immunosorbent assay (ELISA), Western blot, flow cytometry assay, and immunofluorescence staining. The Starbase database and dual luciferase reporter assay were used to predict and validate the targeting relationship between miR-96-5p and PPARγ, and rescue assay was performed to gain insight into the role of miR-96-5p on IDD through PPARγ/NF-κB signaling.
RESULTS: PPARγ expression reduced with concentration and time under IL-1β stimulation, while miR-96-5p expression showed the reverse trend (P