Small activating RNA induces myogenic differentiation of rat adipose-derived stem cells by upregulating MyoD

ABSTRACTPurpose:RNA activation (RNAa) is a mechanism of gene activation triggered by promoter-targeted small double stranded RNAs (dsRNAs), also known as small activating RNAs (saRNAs). Myogenic regulatory factor MyoD is regarded as the master activator of myogenic differentiation cascade by binding to enhancer of muscle specific genes. Stress urinary incontinence (SUI) is a condition primarily resulted from urethral sphincter deficiency. It is thus expected that by promoting differentiation of adipose-derived stem cells (ADSCs) into myoblasts by activating MyoD gene through RNAa may offer benefits to SUI.Materials and Methods:Rats ADSCs were isolated, proliferated in vitro, and identified by flow cytometry. Purified ADSCs were then transfected with a MyoD saRNA or control transfected. Real-time polymerase chain reaction (RT-PCR) and western blotting were used to detect MyoD mRNA and protein expression, respectively. Immunocytochemical staining was applied to determine the expression of desmin protein in transfected cells. Cell viability was measured by using CellTiter 96® AQueous One Solution Cell Proliferation Assay kit.Results:Transfection of a MyoD saRNA (dsMyoD) into ADSCs significantly induced the expression of MyoD at both the mRNA and protein levels, and inhibited cell proliferation. Desmin protein expression was detected in dsMyoD treated ADSCs 2 weeks later.Conclusion:Our findings show that RNAa mediated overexpression of MyoD can promote transdifferentiation of ADSCs into myoblasts and may help treat stress urinary incontinence (SUI)–a condition primarily resulted from urethral sphincter deficiency.

Decreased Expression of Vitamin K Epoxide Reductase Complex Subunit 1 in Kidney of Patients with Calcium Oxalate Urolithiasis / 华中科技大学学报（医学）（英德文版）

Urinary prothrombin fragment 1 (UPTF1) is a potent inhibitor of urinary stone formation.UPTF1 exerts such inhibitory effect by effective γ-carboxylation in which vitamin K epoxide reductase complex subunit 1 (VKORC1),the rate-limiting enzyme,is involved.This study examined the correlation between VKORC1 expression and calcium oxalate urolithiasis.The renal cortex samples were obtained from patients undergoing nephrectomy and then divided into 3 groups:urolithiasis group,control group A [hydronephrosis-without-stone (HWS) group],control group B (normal control group).The localization and expression of VKORC 1 in renal tissues were determined by using immunohistochemistry,immunofluorescence microscopy,Western blotting and SYBR Green Ⅰreal-time reverse-transcription PCR.The rapid amplification of cDNA ends (RACE) were conducted to obtain the 3'- and 5'-untranslated region (UTR) of VKORC1.The results showed that VKORC1was located in the cytoplasm of renal tubular epithelial cells.The expression of VKORC 1 in the urolithiasis group was significantly lower than that in the other two control groups (P＜0.05).Moreover,the 3'- and 5'-UTR sequence of the VKORC 1 gene was successfully cloned.No insertion or deletion was found in the 3'- and 5'-UTR.However,a 171-bp new base sequence was discovered in the upstream of 5'-UTR end in the urolithiasis group.It was concluded that the decreased expression of VKORC1 may contribute to the development of calcium oxalate urolithiasis in the kidney.

Solitary Fibrous Tumor in Bladder: A Case Report / 华中科技大学学报（医学）（英德文版）

Solitary fibrous tumor (SFT) in bladder is extremely rare. In this study, we reported one case of bladder SFT and reviewed the only ten cases of the disease that had been reported so far. The patient suffered from residual urine sensation and urethral pain. Cystoscopy revealed a 7-cm protruding mass at the dome of the bladder, and bladder mucosa biopsy showed normal differentiation of the bladder mucosa with a small amount of inflammatory cells. Radical resection of the tumor was performed in this patient. Pathological examination found uniform, haphazardly arranged spindle cells, the majority of which were CD34-positive and Vimentin-positive and proved that the mass was a solitary fibrous tumor. Within a period of 9 months of follow-up, no reoccurrence was found.

Genetic Mutation of Vitamin K-dependent Gamma-glutamyl Car-boxylase Domain in Patients with Calcium Oxalate Urolithiasis / 华中科技大学学报（医学）（英德文版）

To investigate the exon mutation of vitamin K-dependent gamma-glutamyl carboxylase (GGCX or VKDC) in patients with calcium oxalate urolithasis, renal cortex and peripheral blood sam-ples were obtained from severe hydronephrosis patients (with or without calculi), and renal tumor pa-tients undergoing nephrectomy. GGCX mutations in all 15 exons were examined in 44 patients with calcium oxalate urolithiasis (COU) by polymerase chain reaction (PCR) and denatured high pressure liquid chromatography (DHPLC), and confirmed by sequencing. Mutation was not found in all COU samples compared to the controls. These data demonstrated that functional GGCX mutations in all 15 exons do not occur in most COU patients. It was suggested that there may be no significant association between the low activity and mutation of GGCX in COU.

The Expression and Implication ofTRPV5, Calbindin-D28k and NCX1 in Idiopathic Hypercalciuria / 华中科技大学学报（医学）（英德文版）

Summary: The expression of calcium epithelium TRPV5, alcium binding protein Calbindin-D28k and Na+/Ca2+ exchanger NCX1 was detected in renal distal convoluted tubule, and their effects on urine calcium reabsorption and the possible pathogenic mechanism in idiopathic hypercalciuria (IH) were investigated. Genetic hypercalciuric stone-forming (GHS) rats were chosen as animal models to study urine calcium reabsorption and IH. The cognate female and male rats that had maximal urine calcium were matched to breed next generation. Twelve GHS rats and 12 normal control (NC) SD rats were selected. Western blot and real time quantitative PCR were used to detect the protein and gene expression of TRPV5, Calbindin-D28k and NCX1 respectively. The expression levels of TRPV5 protein and mRNA in GHS rats were significantly lower than in NC rats (P<0.05). Western blot revealed that the expression levels of Caibindin-D28k in GHS rats and NC rats were 0.49±0.02 and 0.20±0.01 respectively, with the difference being significant between them (P<0.05). By using real time quantitative PCR, it was found that there was no significant difference in Calbindin-28k mRNA expression levels between GHS rats and NC rats (P0.05). There was no significant difference in the NCX1 expression between GHS rats and NC rats (P0.05). It was suggested that TRPV5 and Caibindin-D28k might play an important role in urine calcium reabsorption and IH, but they differently contributed to the pathogenesis: The down-regulation of TRPV5 decreases urine calcium reabsorption, directly leading to loss of the urine calcium and resulting in hypercalciuria, and the increased Calbindin-D28k expression could relieve, neutralize and decrease intracellular Ca2+ concentration to maintain calcium balance. NCX1 is not the key protein in urine calcium reabsorption.