ABSTRACT
@#Objective To investigate the effect and underlying mechanism of Qingguang’an Granules (青光安颗粒剂, QGAG) on mitochondrial autophagy (mitophagy) of retinal ganglion cells (RGCs) in rats with chronic ocular hypertension (COH). Methods Sixty Sprague Dawley (SD) rats, half males and half females, were randomly assigned to three groups: the control, model, and QGAG (2.5 g/kg) groups, with 20 rats in each group. Rats’ model of COH was established by cauterizing episcleral veins in the model group and QGAG group. Three weeks after successful modeling, rats in the QGAG group were intragastrically administered with QGAG, while rats in the control group and the model group received an equal dose of normal saline. After three months of intragastric administration, intraocular pressure (IOP) of all rats was measured. The mitophagy was monitored by the immunofluorescence method, the mitochondrial membrane potential was measured using the JC-1 method, and the morphological changes of mitophagy in RGCs were observed by transmission electron microscopy. Meanwhile, rat RGCs were labeled using the fluorescent gold method, and RGCs density in each group was calculated. Moreover, RGCs apoptosis was observed by TdT-mediated dUTP Nick-End Labeling (TUNEL) assay. Finally, the expression levels of Parkin, optineurin, microtubule-associated protein 1 light chain 3-II/microtubule-associated protein 1 light chain 3-I (LC3-II/LC3-I), recombinant lysosomal associated membrane protein 1 (LAMP1), and B-cell lymphoma-2 (Bcl-2) in RGCs were determined by Western blot assay. The corresponding mRNAs were detected through quantitative real-time polymerase chain reaction (qRT-PCR). Results The QGAG reduced IOP in COH rats, and inhibited mitophagy and apoptosis of RGCs (P < 0.05). Besides, the QGAG significantly increased the expression levels of Parkin and Bcl-2 (P < 0.05), and inhibited the expression levels of optineurin, LAMP1, and LC3-II/LC3-I (P < 0.05) in RGCs of COH rats. Conclusion The QGAG can inhibit mitophagy in RGCs of COH rats and show a protective effect against optic nerve damage caused by glaucoma, which may be mediated through the mitophagy ubiquitination via the Parkin/PINK1-related pathway.
ABSTRACT
BACKGROUND: Cocaine- and amphetamine-regulated transcript (CART), discovered initially by via differential display RT-PCR analysis of brains of rats administered cocaine, is expressed mainly in central nervous system or neuronal origin cells, and is involved in a wide range of behaviors, such as regulation of food intake, energy homeostasis, and reproduction. The hens egg-laying rate mainly depends on the developmental status of follicles, expression of CART have not been identified from hen follicles, the regulatory mechanisms of CART biological activities are still unknown. The objective of this study was to characterize the mRNA expression of CART in hen follicular granulosa cells and determine CART peptide localization and regulatory role during follicular development. METHODS: Small white follicles (1-2 mm in diameter) were treated for RNA isolation; Small white follicles (1-2 mm in diameter) and large white follicles (4-6 mm in diameter) were treated for immunohistochemical localization and large white follicles (4-6 mm in diameter), small yellow follicles (6-8 mm in diameter), large yellow follicles (9-12 mm in diameter), mature follicles (F5, F4, F3, F2, F1, >12 mm in diameter) were treated for RNA isolation and Real time PCR. RESULTS: The results showed that full length of the CDS of hen CART was 336 bp encoding a 111 amino acid polypeptide. In the hen ovary, CART peptide was primarily localized to the theca layer, but not all, the oocyte and granulosa layer, with diffused, weaker staining than relative to the theca cell layer. Further, amount of CART mRNA was more (P < 0.05) in granulosa cells of 6-8 mm follicles compared with that in granulosa cells of other follicles. However, CART mRNA amount was greater in theca cells of 4-6 mm follicles relative to follicles of other sizes (P < 0.05). CONCLUSIONS: Results suggest that CART could play a potential role in developmental regulation of chicken follicles.