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Diabetic nephropathy is a serious complication of diabetes. Hyperoside has been widely reported to ameliorate diabetes-associated disease. The current study is designed to explore the mechanism of hyperoside in diabetic nephropathy. In the present study, high glucose was used to treat podocytes. Diabetic nephropathy mice models were established by high-fat feeding followed by multiple low dose injections of streptozocin. Western blot analysis was conducted for detection of extracellular matrix accumulation, inflammatory response and cell apoptosis. We found out that hyperoside improved high glucose-induced cell injury. Additionally, hyperoside prevented mice with diabetic nephropathy from diabetic symptoms and renal dysfunction. Mechanistically, hyperoside inhibited the mRNA and protein expression of APC. MiR-499–5p was found to be an upstream negative mediator of APC, and hyperoside induced the upregulation of miR-499–5p. MiR-499–5p bound with the 3’ untranslated region of APC to inhibit its expression. Finally, rescue assays revealed that the suppressive effects of miR-499–5p overexpression on renal dysfunction were rescued by upregulation of APC in mice with diabetic nephropathy. In conclusion, these findings indicated that hyperoside ameliorates diabetic nephropathy via targeting the miR-499–5p/APC axis, suggesting that hyperoside may offer a potential tactic for diabetic nephropathy treatment.

MicroRNAs (miRNAs) are a class of small non-coding RNAs that negatively regulate gene expression of target messenger RNAs (mRNAs) and miRNAs have been proven to play vital roles in skeletal muscle development. The miRNA-499-5p has been reported to be negatively related with the expression of Sox6, a critical transcription factor for the maintenance of fast-twitch skeletal muscle. In this study, we amplified a length of 2012-bp mRNA that contains a 1512-bp porcine Sox6 (pSox6) 3'UTR from skeletal muscle of a Duroc×Landrace×Yorkshire pig. By luciferase reporter assay we verified that pSox6 is a target of miR-499-5p. In extensor digitorum longus and Soleus muscles of pigs, the expression levels of miR-499-5p and pSox6 mRNA were also inversely correlated. Besides, overexpression of miR-499-5p in porcine satellite cells promoted the expression of MyHC I and MyHC IIa mRNA, along with a reduction of pSox6 mRNA. Taken together, these results indicate that miR-499-5p may facilitate the oxidative myofibers formation by downregulating pSox6 expression.

Perinatal hypoxic-ischemic encephalopathy (HIE) is associated with high neonatal mortality and permanent neurologic deficit. Recent data suggested microRNAs (miRNAs) may have essential functions in the regulation of HIE. This study aims to investigate the functional role of miR-499-5p and the underlying mechanism in regulating neonatal hypoxia-ischemia (HI)-induced brain injury. Dual-luciferase reporter assay and western blotting assay were performed to investigate the relationship between miR-499-5p and C-reactive protein (CRP). TUNEL staining assay was applied to evaluate neuronal cell apoptosis in the hippocampus after administration of miR-499-5p in HIE rat model. Neurobehavioral assays were conducted to evaluate the effect of miR-499-5p on the neurological functions of rat pups with HI-induced brain injury. Our study showed that miR-499-5p regulated CRP expression in L-02 cells and rat HIE model. The miR-499-5p treatment resulted in significant reduction of neuronal cell apoptosis and the infarct size of the brain. Furthermore, administration of miR-499-5p significantly improved spatial learning ability, spatial memory, and locomotor function of rat pups with HIE. Our data demonstrated that miR-499-5p have a neuroprotective effect in HI-induced brain injury in rat pups, which suggests a potential therapeutic application of miR-499-5p in the treatment of neonatal HIE., (Copyright © 2019 Elsevier B.V. and Japan Neuroscience Society. All rights reserved.)

Aims: This study aimed to investigate the role of microRNA-499-5p (miR-499-5p) in the regulation of skeletal myofiber specification and its underlying mechanisms., Main Methods: Mouse C2C12 cells were used in this study. Cyclosporin A and siRNA targeting Thrap1 (si-Thrap1) were used to inhibit NFATc1/MEF2C pathway and knockdown Thrap1, respectively. The expressions of miR-499-5p and genes were evaluated by real-time quantitative PCR and western blot analysis., Key Findings: Overexpression of miR-499-5p promoted oxidative fiber gene expression and repressed glycolytic fiber gene expression, affecting several factors associated with fiber specification including NFATc1/MEF2C pathway, PGC-1α, FoxO1 and Wnt5a. Inhibition of NFATc1/MEF2C pathway partly reduced the effect of miR-499-5p overexpression on muscle fiber gene expression. MiR-499-5p targeted Thrap1 in proliferating and differentiating C2C12 cells. Knockdown of Thrap1 showed a parallel function with miR-499-5p overexpression on muscle fiber gene expression and NFATc1/MEF2C pathway, accompanied by an increase of miR-499-5p level. The effects of miR-499-5p inhibitor on muscle fiber type specific gene expression and NFATc1/MEF2C pathway were effectively reversed by Thrap1 knockdown., Significance: MiR-499-5p regulated skeletal myofiber specification and affected several factors associated with fiber specification. MiR-499-5p regulated muscle gene expression partly through NFATc1/MEF2C pathway. We also showed a clue that miR-499-5p regulates skeletal muscle fiber specification in C2C12 cells through targeting Thrap1, thereby, promoting NFATc1/MEF2C pathway and then triggering a series of oxidative muscle fiber gene expression., (Copyright © 2018 Elsevier Inc. All rights reserved.)

MicroRNAs (miRNAs) are a class of small non-coding RNAs that negatively regulate gene expression of target messenger RNAs (mRNAs) and miRNAs have been proven to play vital roles in skeletal muscle development. The miRNA-499-5p has been reported to be negatively related with the expression of Sox6, a critical transcription factor for the maintenance of fast-twitch skeletal muscle. In this study, we amplified a length of 2012-bp mRNA that contains a 1512-bp porcine Sox6 (pSox6) 3'UTR from skeletal muscle of a Duroc×Landrace×Yorkshire pig. By luciferase reporter assay we verified that pSox6 is a target of miR-499-5p. In extensor digitorum longus and Soleus muscles of pigs, the expression levels of miR-499-5p and pSox6 mRNA were also inversely correlated. Besides, overexpression of miR-499-5p in porcine satellite cells promoted the expression of MyHC I and MyHC IIa mRNA, along with a reduction of pSox6 mRNA. Taken together, these results indicate that miR-499-5p may facilitate the oxidative myofibers formation by downregulating pSox6 expression.