AIM: To observe the effect of piceatannol on the kidney of diabetic nephropathy rats in early stage, and to explore the possible mechanisms.METHODS: The rats were randomly divided into 5 groups: control group, model group, low dose of piceatannol treatment group, medium dose of piceatannol treatment group and high dose of piceatannol treatment group.The rat model of diabetic nephropathy was induced accordingly, and the rats received 20 mg/kg, 40 mg/kg or 60 mg/kg of piceatannol by gavage once a day for 4 weeks.Blood glucose was detected by glucometer.The urea nitrogen and creatinine levels in the serum were measured by urease-glutamate dehydrogenase enzymatic and inosine acid oxidase methods, respectively, and 24 h urinary microalbumin was analyzed by immune transmission turbidimetry test.Moreover, the pathological changes of the kidney tissues were observed under microscope with HE staining.The protein expression of TGF-β1 and Smad 7 and the phosphorylation levels of Smad2 and Smad3 were determined by Western blot.RESULTS: Compared with model group, piceatannol treatment significantly decreased the levels of blood glucose, blood urea nitrogen and urinary microalbumin, but had no effects on serum creatinine.Furthermore, HE staining showed that the increased mesangial cells, matrix hyperplasia and degenerated epithelial cells in model group were markedly inhibited after piceatannol treatment.Additionally, piceatannol treatment also reduced the protein expression of TGF-β1 and Smad 7, and the phosphorylation levels of Smad2 and Smad3.CONCLUSION: Piceatannol attenuates pathological progression in the kidney of diabetic nephropathy rats in early stage, which may be through inhibiting TGF-β/Smad signaling pathway.

The choice of females to accept or reject male courtship is a critical decision for animal reproduction. Serotonin (5-hydroxytryptamine; 5-HT) has been found to regulate sexual behavior in many species, but it is unclear how 5-HT and its receptors function to regulate different aspects of sexual behavior. Here we used Drosophila melanogaster as the model animal to investigate how 5-HT and its receptors modulate female sexual receptivity. We found that knockout of tryptophan hydroxylase (Trh), which is involved in the biosynthesis of 5-HT, severely reduced virgin female receptivity without affecting post-mating behaviors. We identified a subset of sexually dimorphic Trh neurons that co-expressed fruitless (fru), in which the activity was correlated with sexual receptivity in females. We also found that 5-HT_1A and 5-HT₇ receptors regulate virgin female receptivity. Our findings demonstrate how 5-HT functions in sexually dimorphic neurons to promote virgin female receptivity through two of its receptors.
Animals ; Male ; Female ; Drosophila/physiology* ; Drosophila melanogaster/physiology* ; Serotonin ; Drosophila Proteins/physiology* ; Sexual Behavior, Animal/physiology* ; Transcription Factors ; Nerve Tissue Proteins