The Roles of LncRNAs in Osteogenesis, Adipogenesis and Osteoporosis

BACKGROUND

Osteoporosis (OP) is the most common bone disease, which is listed by the World Health Organization (WHO) as the third major threat to life and health among the elderly. The etiology of OP is multifactorial, and its potential regulatory mechanism remains unclear. Long non-coding RNAs (LncRNAs) are the non-coding RNAs that are over 200 bases in the chain length. Increasing evidence indicates that LncRNAs are the important regulators of osteogenic and adipogenic differentiation, and the occurrence of OP is greatly related to the dysregulation of the bone marrow mesenchymal stem cells (BMSCs) differentiation lineage. Meanwhile, LncRNAs affect the occurrence and development of OP by regulating OP-related biological processes.

METHODS

In the review, we summarized and analyzed the latest findings of LncRNAs in the pathogenesis, diagnosis and related biological processes of OP. Relevant studies published in the last five years were retrieved and selected from the PubMed database using the keywords of LncRNA and OP.

RESULTS/CONCLUSION

The present study aimed to examine the underlying mechanisms and biological roles of LncRNAs in OP, as well as osteogenic and adipogenic differentiation. Our results contributed to providing new clues for the epigenetic regulation of OP, making LncRNAs the new targets for OP therapy.

Comparative proteomic analysis of proteins influenced by melanin-concentrating hormone and melanin-concentrating hormone receptor 2 interaction

Melanin-concentrating hormone receptor 2 (MCHR2), a second G protein-coupled receptor for melanin-concentrating hormone (MCH), has been known for many years. However, its physiological function is poorly understood. To identify the proteins involved in MCHR2 physiological function, a comparative proteomic analysis of protein expression in SH-SY5Y cells stably expressing human MCHR2 (SH-SY5Y-MCHR2) and control SH-SY5Y cells (SH-SY5Y-mock) - both treated with MCH - was conducted. Significant changes were observed in the expression of 34 proteins, including isocitrate dehydrogenase (NAD) subunit alpha, mitochondrial (IDH3A), phosphoenolpyruvate carboxykinase 1 (PCK1), 6-phosphofructo-2-kinase/fructose-2.6-biphosphatase 4 (PFKFB4), insulin-induced gene 2 protein (INSIG2), and acyl-coenzyme A thioesterase 8 (ACOT8). Among the proteins, IDH3A, PCK1, PFKFB4 increased significantly, and INSIG2, ACOT8 decreased significantly in experimental cells compared with control cells; these findings were further confirmed by semi-quantitative RT-PCR and Western blot analysis. The comparative proteome data may provide a valuable clue to further understand MCHR2 physiological function, and several differentially regulated proteins may be used as target proteins for the development of novel drugs.

Linkage analysis of families with autosomal dominant polycystic kidney disease by KG8-CA marker

BACKGROUND

Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common genetic diseases of human. Traditionally, ADPKD is diagnosed by ultrasonography, computed tomography (CT) or magnetic resonance imaging (MRI) of kidneys for the presence of renal cysts. Individuals who carry the defective gene but have not yet developed cysts in kidney may not be diagnosed. Genetic analysis reveals it to be caused mostly by a single-gene disorder of a genetic locus, designated PKD1. Recently, the genetic locus involving PKD1 has been identified on chromosome 16p13.3, and has been cloned and completely sequenced.

METHODS

A pair of primers, KG8-CA, located between D16S84 and D16S125, was selected and synthesized for the polymerase chain reaction (PCR) to identify individuals who may carry the defective locus. The sequence of KG8-CA primers, was 5'-CTCCCAGGGTGGAGGAAGGTG-3' and 5'-GCAGGCACAGCCAGCTCCGAG-3'. PCR products were analyzed in denaturing condition, using gel containing 8% acrylamide and 7M urea. Autoradiography was carried out to interpret the results.

RESULTS

Four Chinese families with history of ADPKD showed different DNA patterns in individuals with ADPKD and in normal individuals. Among the members in four families with history of ADPKD, every individual shared a common DNA band, suggesting that this band was derived from normal PKD1 allele. On the other hand, individuals diagnosed to have ADPKD showed one or two additional DNA bands which migrated differently from the common DNA band and should therefore be derived from defective ADPKD allele. Previous studies have shown that the ADPKD allele is highly polymorphic, as was evident in these family studies.

CONCLUSIONS

Among the members from these four families, some were clinically normal and had DNA pattern that was typical to patients with ADPKD. These individuals might carry the defective PKD1 allele but have not yet developed the ADPKD symptoms. Therefore, the method described in this study has diagnostic values for pre-symptomatic individuals as well as for patients already diagnosed with ADPKD.

Detection of human cytomegalovirus in cervicovaginal cells by culture, in situ DNA hybridization and DNA amplification methods

The presence of human cytomegalovirus (HCMV) was tested in 388 cervicovaginal cells specimens obtained from the same number of pregnant women. HCMV was detected in 5.41%, 11.6% and 13.9% of these specimens by conventional culture, in situ DNA hybridization and polymerase chain reaction (PCR) methods, respectively. The sensitivities of detecting HCMV by in situ hybridization and PCR methods were 76.2% and 90.5% and the specificities were 92.1% and 90.5%, respectively, when compared with conventional culture method. The PCR compared favourably with both conventional culture and in situ hybridization methods and it may become a valuable and useful tool for the early and rapid detection of HCMV in clinical specimens.