Acyl ghrelin, desacyl ghrelin and their ratio affect hepatic steatosis via PPARγ signaling pathway

BACKGROUND AND STUDY AIMS

Ghrelin is an appetite hormone-containing 28-amino acid and has 4 different forms in the body. Ghrelin forms have different physiological functions in the body. This study aims to analyze the effect of acyl and desacyl ghrelin hormone on hepatic steatosis and biochemical findings in 36 male Wistar rats.

MATERIALS AND METHODS

Rats were split into 6 equal groups, consisting of control, acyl ghrelin, desacyl ghrelin, acyl/desacyl 3:1, acyl/desacyl 1:1, and acyl/desacyl 1:3 groups, and administered placebo or 200 ng/kg hormone subcutaneous twice a day for 14 days. Oral Glucose Tolerance Test (OGTT) was performed on Day 15, Insulin Tolerance Test (ITT) on Day 16, and scarification procedure on Day 17. Certain biochemical data and liver diacylglycerol (DAG), glycogen, protein kinase C and PPAR-γ levels were detected in the blood. Histological analyses were also conducted on the liver tissues.

RESULTS

The highest plasma total cholesterol and VLDL-K levels were found in the acyl/desacyl 1:3 group, and lower insulin, and HOMA-IR levels were found in groups where acyl and desacyl were administered together (p < 0.05). PPAR-γ gene expression level increased in acyl ghrelin and acyl/desacyl 1:3 groups compared to the control group. Protein kinase C gene expression was highest in the acyl/desacyl 1:3 group. The most severe degenerative findings compliant with steatosis in the liver were observed in the acyl ghrelin group (p < 0.05).

CONCLUSION

It was determined that administering rats acyl alone and acyl/desacyl by 1:3 caused the highest PPAR-γ gene expression, serum total cholesterol, HDL-K, and VLDL-K levels in the body. Besides, it is shown that desacyl ghrelin effectively regulates the blood glucose level when administered alone.

Effects of iloprost on experimental ischemia and reperfusion injury in rat ovary

We investigated the protective effect of iloprost against ischemia/reperfusion (I/R) injury in rat ovary. We used 32 female Sprague-Dawley rats randomly allocated to four experimental groups: sham, ischemia, I/R and I/R + iloprost. Ovarian torsion was established in all rats except the sham group. The torsion group was exposed to ischemia for 3 h. The detorsion group was exposed to 3 h ischemia applied + 3 h reperfusion. The detorsion + iloprost group was exposed to ischemia for 3 h + reperfusion for 3 h + intravenous (IV) iloprost infusion for 60 min starting at the beginning of reperfusion. Ovaries were removed and prepared for histopathological evaluation. Reduced glutathione (GSH) and malondialdehyde (MDA) were measured in the blood. The total histopathological injury score and MDA level of the ischemia group were significantly higher than for the sham group. Ovarian injury score and MDA level following I/R increased compared to the ischemia group. Iloprost administration reduced the total injury score and MDA level. The GSH level was higher in the I/R + iloprost group than in the I/R group. We concluded that IV iloprost administration reduces I/R injury in rat ovarian tissue.

Investigation of the effects of acrylamide applied during pregnancy on fetal brain development in rats and protective role of the vitamin E

A liberal amount of acrylamide (AA) is produced as a result of frying or baking foods in high temperatures, and individuals take certain amounts of AA everyday by consuming these food items. Pregnant women are also exposed to AA originating from food during pregnancy and their fetus are probably affected. The rats were divided into five different groups: control (C), corn oil (CO), vitamin E (Vit E), AA, and Vit E + AA, with eight pregnant rats in each group. On the 20th day of pregnancy, fetuses were removed and brain tissues of fetuses were examined for biochemical and histological changes. AA caused degeneration in neuron structures in fetal brain tissue and caused hemorrhagic damages; dramatically decreased brain-derived neurotrophic factor levels; increased malondialdehyde, total oxidant capacity levels; and decreased reduced glutathione and total antioxidant capacity levels (p < 0.05). On the other hand, it was determined that the Vit E, a neuroprotectant and a powerful antioxidant, suppressed the effects of AA on fetal development and fetal brain tissue damage for the above-mentioned parameters (p < 0.05). It is recommended to consume food containing Vit E as a protection to minimize the toxic effects of food-oriented AA on fetus development due to the widespread nature of fast-food culture in today's life and the impossibility of protection from AA toxicity.