Myocardial contractile dysfunction is associated with an increase in mitochondrial fission in patients with diabetes. However, whether mitochondrial fission directly promotes diabetes‐induced cardiac dysfunction is still unknown. Melatonin exerts a substantial influence on the regulation of mitochondrial fission/fusion. This study investigated whether melatonin protects against diabetes‐induced cardiac dysfunction via regulation of mitochondrial fission/fusion and explored its underlying mechanisms. Here, we show that melatonin prevented diabetes‐induced cardiac dysfunction by inhibiting dynamin‐related protein 1 (Drp1)‐mediated mitochondrial fission. Melatonin treatment decreased Drp1 expression, inhibited mitochondrial fragmentation, suppressed oxidative stress, reduced cardiomyocyte apoptosis, improved mitochondrial function and cardiac function in streptozotocin (STZ)‐induced diabetic mice, but not in SIRT1−/− diabetic mice. In high glucose‐exposed H9c2 cells, melatonin treatment increased the expression of SIRT1 and PGC‐1α and inhibited Drp1‐mediated mitochondrial fission and mitochondria‐derived superoxide production. In contrast, SIRT1 or PGC‐1α siRNA knockdown blunted the inhibitory effects of melatonin on Drp1 expression and mitochondrial fission. These data indicated that melatonin exerted its cardioprotective effects by reducing Drp1‐mediated mitochondrial fission in a SIRT1/PGC‐1α‐dependent manner. Moreover, chromatin immunoprecipitation analysis revealed that PGC‐1α directly regulated the expression of Drp1 by binding to its promoter. Inhibition of mitochondrial fission with Drp1 inhibitor mdivi‐1 suppressed oxidative stress, alleviated mitochondrial dysfunction and cardiac dysfunction in diabetic mice. These findings show that melatonin attenuates the development of diabetes‐induced cardiac dysfunction by preventing mitochondrial fission through SIRT1‐PGC1α pathway, which negatively regulates the expression of Drp1 directly. Inhibition of mitochondrial fission may be a potential target for delaying cardiac complications in patients with diabetes.

BackgroundThis meta-analysis aimed to evaluate the postoperative clinical outcomes and safety of the direct anterior approach (DAA) versus posterior approach (PA) in total hip arthroplasty (THA).MethodsWe searched PubMed, Embase, Web of Science, the Cochrane Library, and Google databases from inception to June 2018 to select studies that compared the DAA and PA for THA. Only randomized controlled trials (RCTs) were included. Outcomes included Harris hip score at 2 weeks, 6 weeks, 12 weeks, and 1 year; VAS at 24 h, 48 h, and 72 h; incision length, operation time, postoperative blood loss, length of hospital stay, and complications (intraoperative fracture, postoperative dislocation, heterotopic ossification (HO), and groin pain).ResultsNine RCTs totaling 754 THAs (DAA group = 377, PA group = 377) met the criteria to be included in this meta-analysis. The present meta-analysis indicated that, compared with PA group, DAA group was associated with an increase of the Harris hip score at the 2-week and 4-week time points. No significant difference was found between DAA and PA groups of the Harris hip scores at 12 weeks, 1 year length of hospital stay (p > 0.05). DAA group was associated with a reduction of the VAS at 24 h, 48 h, and 72 h with statistical significance (p < 0.05). What is more, DAA was associated with a reduction of the incision length and postoperative blood loss (p < 0.05). There was no significant difference between the operation time and complications (intraoperative fracture, postoperative dislocation, HO, and groin pain).ConclusionIn THA patients, compared with PA, DAA was associated with an early functional recovery and less pain scores. What is more, DAA was associated with shorter incision length and blood loss.

The Vespertilionidae is the largest family in the order Chiroptera and has a worldwide distribution in the temperate and tropical regions. In order to further clarify the karyotype relationships at the lower taxonomic level in Vespertilionidae, genome-wide comparative maps have been constructed between Myotis myotis (MMY, 2n = 44) and six vesper bats from China: Myotis altarium (MAL, 2n = 44), Hypsugo pulveratus (HPU, 2n = 44), Nyctalus velutinus (NVE, 2n = 36), Tylonycteris robustula (TRO, 2n = 32), Tylonycteris sp. (TSP, 2n = 30)and Miniopterus fuliginosus (MFU, 2n = 46) by cross-species chromosome painting with a set of painting probes derived from flow-sorted chromosomes of Myotis myotis. Each Myotis myotis autosomal probe detected a single homologous chromosomal segment in the genomes of these six vesper bats except for MMY chromosome 3/4 paint which hybridized onto two chromosomes in the genome of M. fuliginosus. Our results show that Robertsonian translocation is the main mode of karyotype evolution in Vespertilionidae and that the addition of heterochromatic material also plays an important role in the karyotypic evolution of the genera Tylonycteris and Nyctalus. Two conserved syntenic associations (MMY9 + 23 and 18 + 19) could be the synapomorphic features for the genus Tylonycteris. The integration of our maps with the published maps has enabled us to deduce chromosomal homologies between human and these six vesper bats and provided new insight into the karyotype evolution of the family Vespertilionidae.

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