Shrm4 contributes to autophagy inhibition and neuroprotection following ischemic stroke by mediating GABAB receptor activation.

Acute ischemic stroke is one of the leading causes of death in developed countries and the most common cause of disability in adults worldwide. Despite advances in the understanding of stroke pathophysiology, therapeutic options remain limited. In this study, we explored the interaction of Shrm4 and the metabotropic gamma-aminobutyric acid (GABA) receptors (GABAB ) in ischemic stroke. A transient middle cerebral artery occlusion (MCAO) model was induced by filament insertion in Shrm4+/+ and wild-type C57BL/6J mice, followed by reperfusion for up to 7 days. Baclofen was administered was used to activate GABAB in vivo during reperfusion. Neurological deficits, motor and memory functions, and infarct volume were determined in the various mouse groups. Furthermore, we also developed an oxygen-glucose deprivation (OGD) cell model in primary neurons to test Shrm4/GABAB interactions in vitro. Shrm4 was observed to decrease infarct volume and neuronal cell loss in penumbra, and rescue neurological deficits in MCAO mice. Notably, Shrm4 also increased pole climbing speed, reduced foot faults, and increased escape latency in the Morris water maze test, while reducing neuron autophagy through an interaction with GABAB receptors. GABAB activation using baclofen further reduced OGD-induced neuron damage in culture and stroke outcomes of MCAO, relative to Shrm4 alone. Taken together, Shrm4-mediated GABAB activation confers neuroprotection by reducing neuronal autophagy in acute ischemic stroke.

The effects of ABCG2 on the viability, proliferation and paracrine actions of kidney side population cells under oxygen-glucose deprivation.

Bcrp1/ABCG2 is exclusively expressed in side population (SP) cells, however, it has not been fully elucidated whether it has an impact on the viability, proliferation and paracrine actions in kidney SP cells under oxygen-glucose deprivation (OGD) followed by reoxygenation. In this study, we found that 2-h OGD did not injure SP cells (sub-lethal OGD) but induced SP cells proliferation 48 and 72 h after reoxygenation; whereas 4-h OGD markedly injured the cells (lethal OGD) and led to apoptosis 24-72 h after reoxygenation. Fumitremorgin C, an inhibitor of ABCG2, attenuated both the proliferation and viability of SP cells. Sub-lethal and lethal OGD induced the increase in the secretion of vascular endothelial growth factor, insulin-like growth factor 1, hepatocyte growth factor, and stromal cell-derived factor-1α in kidney SP cells, which was inhibited by Fumitremorgin C. Collectively, these findings provide evidence for a crucial role for the ABCG2 expression in the viability, proliferation and paracrine actions of kidney SP cells after OGD.

Efficacy and safety of Shenyankangfu Tablet, a Chinese patent medicine, for primary glomerulonephritis: A multicenter randomized controlled trial.

BACKGROUND: Shenyankangfu Tablet (SYKFT) is a Chinese patent medicine that has been used widely to decrease proteinuria and the progression of chronic kidney disease. OBJECTIVE: This trial compared the efficacy and safety of SYKFT, for the control of proteinuria in primary glomerulonephritis patients, against the standard drug, losartan potassium. DESIGN, SETTING, PARTICIPANTS AND INTERVENTION: This was a multicenter, double-blind, randomized, controlled clinical trial. Primary glomerulonephritis patients, aged 18-70 years, with blood pressure ≤ 140/90 mmHg, estimated glomerular filtration rate (eGFR) ≥ 45 mL/min per 1.73 m2, and 24-hour proteinuria level of 0.5-3.0 g, were recruited in 41 hospitals across 19 provinces in China and were randomly divided into five groups: SYKFT, losartan potassium 50 mg or 100 mg, SYKFT plus losartan potassium 50 mg or 100 mg. MAIN OUTCOME MEASURES: The primary outcome was change in the 24-hour proteinuria level, after 48 weeks of treatment. RESULTS: A total of 735 participants were enrolled. The percent decline of urine protein quantification in the SYKFT group after 48 weeks was 8.78% ± 2.56% (P = 0.006) more than that in the losartan 50 mg group, which was 0.51% ± 2.54% (P = 1.000) less than that in the losartan 100 mg group. Compared with the losartan potassium 50 mg group, the SYKFT plus losartan potassium 50 mg group had a 13.39% ± 2.49% (P < 0.001) greater reduction in urine protein level. Compared with the losartan potassium 100 mg group, the SYKFT plus losartan potassium 100 mg group had a 9.77% ± 2.52% (P = 0.001) greater reduction in urine protein. With a superiority threshold of 15%, neither was statistically significant. eGFR, serum creatinine and serum albumin from the baseline did not change statistically significant. The average change in TCM syndrome score between the patients who took SYKFT (-3.00 [-6.00, -2.00]) and who did not take SYKFT (-2.00 [-5.00, 0]) was statistically significant (P = 0.003). No obvious adverse reactions were observed in any group. CONCLUSION: SYKFT decreased the proteinuria and improved the TCM syndrome scores of primary glomerulonephritis patients, with no change in the rate of decrease in the eGFR. SYKFT plus losartan potassium therapy decreased proteinuria more than losartan potassium therapy alone. TRIAL REGISTRATION NUMBER: NCT02063100 on ClinicalTrials.gov.

Targeted inhibition of hantavirus replication and intracranial pathogenesis by a chimeric protein-delivered siRNA.

Hantavirus (HV) infection, which underlies hantavirus hemorrhagic fever with renal syndrome and hantavirus pulmonary syndrome, remains to be a severe clinical challenge. Here, we synthesized small interfering RNAs (siRNAs) that target the encoding sequences of HV strain 76-118, and validated their inhibitory role in virus replication in HV-infected monkey kidney Vero E6 cells. A chimeric protein, 3G1-Cκ-tP, consisting of a single-chain antibody fragment (3G1) against the HV surface envelop glycoprotein, the constant region of human immunoglobulin κ chain (Cκ), and truncated protamine (amino acids 8-29, tP), was further generated. The fusion protein showed high affinity to HV antigen on the infected cell membrane, and internalized through clathrin-mediated endocytosis; it bound to siRNAs via the basic nucleic acid-rich protamine fragment, leading to their specific delivery into HV-infected cells and efficient inhibition of virus replication. An encephalitis mouse model was established via intracranial HV administration. Intraperitoneal injection of siRNAs complexed with 3G1-Cκ-tP achieved specific distribution of siRNAs in HV-infected brain cells, significantly reduced HV antigen levels, and effective protection from HV infection-derived animal death. These results provide a compelling rationale for novel therapeutic protocols designed for HV infection and related disorders.

Bone integration capability of a series of strontium-containing hydroxyapatite coatings formed by micro-arc oxidation.

Strontium-containing hydroxyapatites (Sr-HA) combine the desirable bone regenerative properties of hydroxyapatites (HA) with anabolic and anti-catabolic effects of strontium cations. In the present work, a series of Sr(y)HA [Sr(y)Ca(10-y)(PO4)6(OH)2; y = 0, 0.5, 1, 2] coatings on titanium are produced by micro-arc oxidation (MAO), and the effects of the in vivo osseointegration ability of the coatings are investigated by using a rabbit model. All samples are subjected to biomechanical, surface elemental, micro-CT and histological analysis after 4 and 12 weeks of healing. The obtained results show that the MAO-formed coatings exhibit a microporous network structure composed of Sr(y)HA/Sr(y)HA-Sr(x)Ca(1-x)TiO3/Sr(x)Ca(1-x)TiO3-TiO2 multilayers, in which the outer Sr(y)HA and intermediate Sr(y)HA-Sr(x)Ca(1-x)TiO3 layers have a nanocrystalline structure. All Sr-HA coated implants induce marked improvements in the behavior of bone formation, quantity and quality of bone tissue around the implants than the control HA implant and in particular, the 20%Sr-HA coating promotes early bone formation as identified by polyfluorochrome sequential labeling. The bone-to-implant contact is increased by 46% (p < 0.05) and the pull-out strength is increased by 103% over the HA group (p < 0.01). Extensive areas of mineralized tissue densely deposit on the 20%Sr-HA coating after biomechanical testing, and the greatest improvement of bone microarchitecture are observed around the 20%Sr-HA implant. The identified biological parameters successfully demonstrate the osteoconductivity of 20%Sr-HA surfaces, which results not only in an acceleration but also an improvement of bone-implant integration. The study demonstrates the immense potential of 20%Sr-HA coatings in dental and orthopedic applications.

[Improvement of osseointegration of titanium dental implant surfaces modified with strontium-substituted hydroxyapatite].

OBJECTIVE: To explore the osteogenic activity of a micro-arc oxidation (MAO)-treated strontium (Sr)-substituted hydroxyapatite (Sr-HA) coating developed to enhance the osseointegration of titanium dental implants, and to investigate the strengthening mechanisms of bone bonding of crystalline hydroxyapatite (HA) with incorporation of strontium in vivo. METHODS: The morphology and phase component of the oxidized film of Sr-HA and HA coated implants were examined by SEM and X-ray diffraction (XRD). Then, twenty-four implants were inserted into the metaphysis of rabbits tibias and femurs using polyfluorochrome sequential labeling. Four and 12 weeks following the surgery, the morphology and chemical composition of the bone-implant interfaces were evaluated by histological examination and energy-dispersive X-ray. RESULTS: The XRD patterns showed that diffraction peaks of HA shift to lower 2θ values with Sr-addition, which resulted in decreases in lattice energy and then crystallinity. Sr-HA coating presented a microporous structure in the SEM observation. Meanwhile, Sr-HA coating exhibited osteogenic activity at the early stage of bone healing period and new bone mineral apposition ratio [(4.75 ± 0.46) microm/d] was significantly higher than that of the control group [(3.21 ± 0.44) microm/d]. An apatite layer was observed at the interface of bone-Sr-HA coating in light microscopy observation and energy-dispersive X-ray analysis. Then the apatite layer was precipitated and formed new bone which became mature bone and bonded tightly to the Sr-HA. CONCLUSIONS: Strontium-substituted hydroxyapatite coating shows high biological activity, which can accelerate the formation of apatite layer, hence the osteogenic ability.

Both strands of siRNA have potential to guide posttranscriptional gene silencing in mammalian cells.

Despite the widespread application of RNA interference (RNAi) as a research tool for diverse purposes, the key step of strand selection of siRNAs during the formation of RNA-induced silencing complex (RISC) remains poorly understood. Here, using siRNAs targeted to the complementary region of Survivin and the effector protease receptor 1 (EPR-1), we show that both strands of the siRNA duplex can find their target mRNA and are equally eligible for assembly into Argonaute 2 (Ago2) of RISC in HEK293 cells. Transfection of the synthetic siRNA duplexes with different thermodynamic profiles or short hairpin RNA (shRNA) vectors that generate double-stranded RNAs (dsRNAs), permitting processing specifically from either the 5' or 3' end of the incipient siRNA, results in the degradation of the respective target mRNAs of either strand of the siRNA duplex with comparable efficiencies. Thus, while most RNAi reactions may follow the thermodynamic asymmetry rule in strand selection, our study suggests an exceptional mode for certain siRNAs in which both strands of the duplex are competent in sponsoring RNAi, and implies additional factors that might dictate the RNAi targets.

[Prokaryotic expression and bioactivity identification of Fab against human gamma-seminoprotein].

AIM: To construct the expression vector containing cDNA encoding Fab against human gamma-seminoprotein and express it in E. coli. METHODS: The genes encoding K chain and Fd against gamma-seminoprotein were acquired from pUC19-K and pBluescript KS( M13-)-Fd by restrictive enzyme digestion and then cloned into the expression vector pComb3 to construct recombinant expression vector pComb3-Fab. pComb3-Fab was transfected into and expressed in XLI-Blue. RESULTS: Fab against r-semino-protein was expressed in. XLI-Blue. Western blot analysis and immunocytochemical staining demonstrated that ex-pressed Fab could specifically bind to gamma-seminoprotein. CONCLUSION: Fab against gamma -seminoprotein has been expressed successfully with biological activity, which create favourable condition for further study on targeted therapy of prostate cancer.