Hypoxia-inducible factor protects against acute kidney injury via the Wnt/ß-catenin signaling pathway.

Promoting adaptive repair in acute kidney injury (AKI) is an effective strategy to prevent the progression from AKI to chronic kidney disease. However, the mechanisms involved in renal repair after AKI remain unclear. In this study, we investigated the role of hypoxia-inducible factor (HIF), an important regulator of ischemic and hypoxic injury, in AKI during the repair phase. We established mouse models of ischemia-reperfusion injury-induced AKI with adaptive repair or maladaptive repair. We found that after injury, activation of HIF in the adaptive repair group was rapid, whereas in the maladaptive repair group HIF activation was relatively delayed, and its expression was significantly lower than that in the adaptive repair group during the early repair phase. To further investigate the mechanism of HIF, we regulated the expression of HIF-1α and HIF-2α in HK-2 cells and EA.hy926 cells, respectively. Silencing HIF expression reduced proliferation and increased apoptosis in cells injured by hypoxia/reoxygenation. Self-healing ability was further reduced due to the downregulation of HIF. Moreover, HIF overexpression had the opposite effect. HIF increased the expression of ß-catenin and its downstream target genes. Activation of Wnt/ß-catenin by the small-molecule activator SKL2001 mitigated the damaging effect of HIF knockdown, whereas blockade of ß-catenin with the inhibitor IWR-1-endo reduced the protective effects of HIF. In conclusion, HIF, which is highly expressed in the early stage after AKI, promotes renal repair by interacting with the Wnt/ß-catenin signaling pathway.NEW & NOTEWORTHY We investigated the role of hypoxia-inducible factor (HIF) in acute kidney injury in vivo and in vitro. Expression of HIF in the adaptive repair group was more rapid and sufficient than that in the maladaptive repair group during the early repair phase. HK-2 and EA.hy926 cells treated with hypoxia/reoxygenation were used to elucidate the cross talk between HIF and the Wnt/ß-catenin signaling pathway by which HIF played a renoprotective role in acute kidney injury.

Comparison of different therapies in high-risk patients with idiopathic membranous nephropathy.

BACKGROUND/PURPOSE: Immunosuppressive therapy plays an important role in patients with high-risk idiopathic membranous nephropathy (IMN), but the therapeutic modality is still controversial. METHODS: Corticosteroid combined with oral tacrolimus (TAC, target trough blood concentration of 4-8 ng/mL), intravenous cyclophosphamide (CYC, 750 mg/m(2)/mo, or oral mycophenolate mofetil (MMF, 1.5-2.0 g/d) were randomly administered for 9 months to 90 patients with IMN proved with renal biopsy with severe proteinuria (>8 g/d). RESULTS: Eighty-six of the 90 patients completed the study. The total remission (TR) rates in the TAC group were significantly higher than those in the CYC group at 1 and 2 months (p < 0.01) and the MMF group at 1-4 months (p < 0.01). The TR rates were 83.3%, 73.3%, and 70.0% in the TAC, CYC, and MMF groups at 9 months (p = 0.457), and there were no significant differences between the three groups from 5 to 9 months. Furthermore, TAC reduced proteinuria and ameliorated hypoalbuminemia more quickly and effectively than CYC and MMF. We observed no severe adverse events in the three groups. CONCLUSION: Tacrolimus combined with corticosteroid had tolerable adverse effects and induced the remission of IMN more effectively and more rapidly. This is the first prospective randomized cohort study to compare three different therapies in patients at high risk for IMN. It provides strong evidence for choosing optimal treatment for patients with IMN. The long-term efficacy of this treatment strategy should be investigated further in future studies.

Bioinformatics and Microarray Analysis of miRNAs in Aged Female Mice Model Implied New Molecular Mechanisms for Impaired Fracture Healing.

Impaired fracture healing in aged females is still a challenge in clinics. MicroRNAs (miRNAs) play important roles in fracture healing. This study aims to identify the miRNAs that potentially contribute to the impaired fracture healing in aged females. Transverse femoral shaft fractures were created in adult and aged female mice. At post-fracture 0-, 2- and 4-week, the fracture sites were scanned by micro computed tomography to confirm that the fracture healing was impaired in aged female mice and the fracture calluses were collected for miRNA microarray analysis. A total of 53 significantly differentially expressed miRNAs and 5438 miRNA-target gene interactions involved in bone fracture healing were identified. A novel scoring system was designed to analyze the miRNA contribution to impaired fracture healing (RCIFH). Using this method, 11 novel miRNAs were identified to impair fracture healing at 2- or 4-week post-fracture. Thereafter, function analysis of target genes was performed for miRNAs with high RCIFH values. The results showed that high RCIFH miRNAs in aged female mice might impair fracture healing not only by down-regulating angiogenesis-, chondrogenesis-, and osteogenesis-related pathways, but also by up-regulating osteoclastogenesis-related pathway, which implied the essential roles of these high RCIFH miRNAs in impaired fracture healing in aged females, and might promote the discovery of novel therapeutic strategies.

[Astragaloside IV regulates STAT1/IκB/NF-κB signaling pathway to inhibit activation of BV-2 cells].

OBJECTIVE: The study was aimed to investigate the inhibitory effect and mechanism of astragaloside IV (ASI) on the activation of microglial cells. METHOD: After pre-incubated with ASI for 2 h, microglial cells BV-2 were stimulated with interferon-γ (IFN-γ) for 1. 5 h and 24 h, respectively. Secretion of nitric oxide (NO) in the medium was measured by Griess method. Production of tumor necrosis factor alpha (TNF-α) was detected by ELISA approach. Cellular gene expressions of CD11b, TNF-α, interleukin 1ß (IL-1ß) and induced nitric oxide synthase (iNOS) were examined by quantitative-PCR analysis. Total and phosphorylation of STAT1, IκB and NF-κB was analyzed by Western blot method. RESULT: ASI could significantly inhibit the increased secretion of TNF-α and NO from BV-2 cells upon IFN-γ stimulation (P < 0.001). Further study showed that ASI significantly down-regulated gene expression of IL-1ß and TNF-α (P < 0.01, P < 0.05) and exhibited a trend to reduce that of iNOS. IFN-γ and ASI have no obvious effect on gene expression of CD11b. Moreover, ASI inhibited the phosphorylation of STAT1, IκB and NF-κB elicited by IFN-γ stimulation. CONCLUSION: ASI could restrain microglial activation through interfering STAT1/IκB/NF-κB signaling pathway, reducing gene expres- sion of IL-1ß and TNF-α, and thus inhibiting the production of proinflammatory mediators such as NO and TNF-α.

Astragalosides from Radix Astragali benefits experimental autoimmune encephalomyelitis in C57BL /6 mice at multiple levels.

BACKGROUND: Radix Astragali is famous for its beneficial effect on inflammation associated diseases. This study was to assess the efficacy of astragalosides (AST) extracted from Radix Astragali, on the progression of experimental autoimmune encephalomyelitis (EAE), and explore its possible underlying molecular mechanisms. METHODS: EAE was induced by subcutaneous immunization of MOG35-55. Infiltration of inflammatory cells was examined by HE staining. ROS level was detected by measuring infiltrated hydroethidine. Leakage of blood brain barrier (BBB) was assessed using Evan's blue dye extravasation method. Levels of inflammatory cytokines were measured using ELISA kits. Activities of total-SOD, GSH-Px, and iNOS and MDA concentration were measured using biochemical analytic kits. Gene expression was detected using real-time PCR method. Protein expression was assayed using western blotting approach. RESULTS: AST administration attenuated the progression of EAE in mice remarkably. Further studies manifested that AST treatment inhibited infiltration of inflammatory cells, lessened ROS production and decreased BBB leakage. In peripheral immune-systems, AST up-regulated mRNA expression of transcriptional factors T-bet and Foxp3 but decreased that of RORγt to modulate T cell differentiation. In CNS, AST stopped BBB leakage, reduced ROS production by up-regulation of T-SOD, and reduced neuroinflammation by inhibition of iNOS and other inflammatory cytokines. Moreover, AST inhibited production of p53 and phosphorylation of tau by modulation of the Bcl-2/Bax ratio. CONCLUSIONS: AST orchestrated multiple pathways, including immuno-regulation, anti-oxidative stress, anti-neuroinflammation and anti-neuroapoptosis involved in the MS pathogenesis, to prevent the deterioration of EAE, which paves the way for the application of it in clinical prevention/therapy of MS.

Non-negligible impact of microplastics on wetland ecosystems.

There has been much concern about microplastic (MP) pollution in marine and soil environments, but attention is gradually shifting towards wetland ecosystems, which are a transitional zone between aquatic and terrestrial ecosystems. This paper comprehensively reviews the sources of MPs in wetland ecosystems, as well as their occurrence characteristics, factors influencing their migration, and their effects on animals, plants, microorganisms, and greenhouse gas (GHG) emissions. It was found that MPs in wetland ecosystems originate mainly from anthropogenic sources (sewage discharge, and agricultural and industrial production) and natural sources (rainfall-runoff, atmospheric deposition, and tidal effects). The most common types and forms of MPs identified in the literature were polyethylene and polypropylene, fibers, and fragments. The migration of MPs in wetlands is influenced by both non-biological factors (the physicochemical properties of MPs, sediment characteristics, and hydrodynamic conditions) and biological factors (the adsorption and growth interception by plant roots, ingestion, and animal excretion). Furthermore, once MPs enter wetland ecosystems, they can impact the resident microorganisms, animals, and plants. They also have a role in global warming because MPs act as unique exogenous carbon sources, and can also influence GHG emissions in wetland ecosystems by affecting the microbial community structure in wetland sediments and abundance of genes associated with GHG emissions. However, further investigation is needed into the influence of MP type, size, and concentration on the GHG emissions in wetlands and the underlying mechanisms. Overall, the accumulation of MPs in wetland ecosystems can have far-reaching consequences for the local ecosystem, human health, and global climate regulation. Understanding the effects of MPs on wetland ecosystems is essential for developing effective management and mitigation strategies to safeguard these valuable and vulnerable environments.

Prodrug of green tea epigallocatechin-3-gallate (Pro-EGCG) as a potent anti-angiogenesis agent for endometriosis in mice.

Green tea epigallocatechin-3-gallate (EGCG) can inhibit angiogenesis and development of an experimental endometriosis model in mice, but it suffers from poor bioavailability. A prodrug of EGCG (pro-EGCG, EGCG octaacetate) is utilized to enhance the stability and bioavailability of EGCG in vivo. In this study, the potential of pro-EGCG as a potent anti-angiogenesis agent for endometriosis in mice was investigated. Homologous endometrium was subcutaneously transplanted into mice to receive either saline, vitamin E, EGCG or pro-EGCG treatment for 4 weeks. The growth of the endometrial implants were monitored by IVIS(®) non-invasive in vivo imaging during the interventions. Angiogenesis of the endometriotic lesions was determined by Cellvizio(®) in vivo imaging and SCANCO(®) Microfil microtomography. The bioavailability, anti-oxidation and anti-angiogenesis capacities of the treatments were measured in plasma and lesions. The implants with adjacent outer subcutaneous and inner abdominal muscle layers were collected for histological, microvessel and apoptosis examinations. The result showed that EGCG and pro-EGCG significantly decreased the growth of endometrial implants from the 2nd week to the 4th week of intervention. EGCG and pro-EGCG significantly reduced the lesion size and weight, inhibited functional and structural microvessels in the lesions, and enhanced lesion apoptosis at the end of interventions. The inhibition by pro-EGCG in all the angiogenesis parameters was significantly greater than that by EGCG, and pro-EGCG also had better bioavailability and greater anti-oxidation and anti-angiogenesis capacities than EGCG. Ovarian follicles and uterine endometrial glands were not affected by either EGCG or pro-EGCG. Vitamin E had no effect on endometriosis. In conclusion, pro-EGCG significantly inhibited the development, growth and angiogenesis of experimental endometriosis in mice with high efficacy, bioavailability, anti-oxidation and anti-angiogenesis capacities. Pro-EGCG could be a potent anti-angiogenesis agent for endometriosis.

Promotion of bone repair by implantation of cryopreserved bone marrow-derived mononuclear cells in a rabbit model of steroid-associated osteonecrosis.

OBJECTIVE: Cytotherapy is an insufficient method for promoting bone repair in steroid-associated osteonecrosis (SAON), and this has been attributed to impairment of the bioactivity of bone marrow-derived stem cells (BMSCs) after pulsed administration of steroids. Cryopreserved autologous bone marrow-derived mononuclear cells (BMMNCs), which contain BMSCs, might maintain their bioactivity in vitro. This study sought to investigate the effects of cryopreserved BMMNCs, before steroid administration, on the enhancement of bone repair in an established rabbit model of SAON. METHODS: For in vitro study, bone marrow was harvested 4 weeks before SAON induction from the iliac crests of rabbits (n = 10) to isolate fresh BMMNCs, and the BMMNCs were then cryopreserved for 8 weeks. Both the fresh and the cryopreserved BMMNCs were evaluated for their bioactivity and osteogenic differentiation capacity. In addition, BMMNCs were isolated 2 weeks after SAON induction and subjected to the same evaluations. For in vivo study, cryopreserved BMMNCs were implanted into the bone tunnel during core decompression of the femur (n = 12 rabbits) after the induction of SAON, and tissue regeneration was evaluated by micro-computed tomography and histologic analyses at 12 weeks postoperation. RESULTS: In vitro, there were no significant differences in the bioactivity or ability to undergo osteogenic differentiation between fresh BMMNCs and cryopreserved BMMNCs, but after SAON induction, both features were decreased significantly. In vivo, the bone mineral density, ratio of bone volume to total volume of bone, and volume and diameter of neovascularization within the bone tunnel were significantly higher in the BMMNC-treated group compared to the nontreated control group at 12 weeks postoperation. CONCLUSION: Cryopreserved BMMNCs maintained their bioactivity and promoted bone regeneration and neovascularization within the bone tunnel after core decompression in this rabbit model of SAON.

Wnt4 is significantly upregulated during the early phases of cisplatin-induced acute kidney injury.

Wnt4 is a secreted growth factor associated with renal tubulogenesis. Our previous studies identified that renal and urinary Wnt4 are upregulated following ischemia-reperfusion injury in mice, but the roles of Wnt4 in other forms of acute kidney injury (AKI) remain unclear. Here, we investigated the changes in Wnt4 expression using a cisplatin-induced AKI model. We found that renal and urinary Wnt4 expression increased as early as 12 hours, peaked at day 4 following cisplatin-induced AKI and was closely correlated with histopathological alterations. By contrast, the serum creatinine level was significantly elevated until day 3, indicating that Wnt4 is more sensitive to early tubular injury than serum creatinine. In addition, renal Wnt4 was co-stained with aquaporin-1 and thiazide-sensitive NaCl cotransporter, suggesting that Wnt4 can detect both proximal and distal tubular injuries. These data were further confirmed in a clinical study. Increased urinary Wnt4 expression was detected earlier than serum creatinine and eGFR in patients with contrast-induced AKI after vascular intervention. This study is the first to demonstrate that increased expression of renal and urinary Wnt4 can be detected earlier than serum creatinine after drug-induced AKI. In particular, urinary Wnt4 can potentially serve as a noninvasive biomarker for monitoring patients with tubular injury.

Urine anti-PLA2R antibody is a novel biomarker of idiopathic membranous nephropathy.

Since urine samples more directly reflect kidney alterations and damage than blood samples, we investigated whether urine anti-PLA2R antibody (uPLA2R-Ab) could be utilized similarly to serum anti-PLA2R antibody (sPLA2R-Ab) as a noninvasive biomarker of idiopathic membranous nephropathy (IMN). In this study, we performed a qualitative analysis using an indirect immunofluorescence test (IIFT) and measured uPLA2R-Ab and sPLA2R-Ab concentrations using an enzyme-linked immunosorbent assay (ELISA) in 28 patients with biopsy-proven IMN and 12 patients with secondary membranous nephropathy (SMN). Overall, 64.3% (n=18) of patients with IMN had IIFT-positive sPLA2R-Ab, 67.9% (n=19) of patients with IMN had IIFT-positive uPLA2R-Ab, and none of the SMN patients had IIFT-positive sPLA2R-Ab or uPLA2R-Ab. The titers of the anti-PLA2R antibody from the IMN patients in the urine (10.72±22.24 RU/µmol, presented as uPLA2R-Ab/urine creatinine) and serum (107.36±140.93 RU/ml) were higher than those from the SMN patients (0.51±0.46 RU/µmol, 0.008±0.029 RU/ml, respectively, p<0.05). Statistical analyses indicated that there were positive correlations between uPLA2R-Ab and gPLA2R, sPLA2R-Ab or urinary protein and negative correlations between uPLA2R-Ab and serum albumin in patients with IMN. In conclusion, uPLA2R-Ab is a novel biomarker of IMN. sPLA2R-Ab combined with uPLA2R-Ab might be more helpful for diagnosis and activity in PLA2R associated MN.

[Review of CO2 and CH4 Emissions from Rivers].

Streams and rivers play a major biogeochemical role in the global carbon cycle and act as hot spots for carbon dioxide (CO2) and methane (CH4) emissions to the atmosphere, excepting their roles of transporting the water and carbon from the terrestrial environment to the ocean. While carbon gases have been of great global concern, systematic reviews are still scarce. Given recent recognition of the pervasiveness of CO2 and CH4 in streams and rivers, this study synthesized existing research and discoveries to identify patterns and controls for riverine CO2 and CH4, knowledge gaps, and research opportunities. This study presented a conceptual framework for sources and the fates of CO2/CH4 from streams and rivers and used this framework to understand the dynamic processes of fluvial carbon evasion and potential anthropogenic disturbances. Multiple environmental influences combined with different contributions of endogenous metabolism and terrigenous input, and the CO2 and CH4 in streams and rivers showed significant spatial and temporal variability on a global scale, regional scale, and watershed scale, which indicates a substantial challenge for understanding the larger-scale dynamics. For a clearer recognition of how the changing environment and human activities may modify fluvial CO2 and CH4 dynamics, this study constructed a system framework of controls on CO2 and CH4 production and persistence in streams and rivers. The framework of controls can be viewed in terms of endogenous environmental controls that influence river metabolism (organic matter, temperature, nutrients, pH, and alternative electron acceptors) and external factors, including geomorphic and hydrologic drivers and human activities (agriculture, damming, and urbanization). We point out that the carbon emissions from rivers should be integrated into the terrestrial carbon budget, and in the future, more attention should be given to research on the sources of CO2 and CH4 in rivers, the generation and diffusion of CO2 and CH4 at different interfaces, the spatiotemporal variability of riverine carbon emissions, and the response of riverine CO2 and CH4 dynamics to the changing environment and human activities.

Multiple Mechanisms are Involved in Salt-Sensitive Hypertension-Induced Renal Injury and Interstitial Fibrosis.

Salt-sensitive hypertension (SSHT) leads to kidney interstitial fibrosis. However, the potential mechanisms leading to renal fibrosis have not been well investigated. In present study, Dahl salt-sensitive (DS) rats were divided into three groups: normal salt diet (DSN), high salt diet (DSH) and high salt diet treated with hydrochlorothiazide (HCTZ) (DSH + HCTZ). A significant increase in systolic blood pressure (SBP) was observed 3 weeks after initiating the high salt diet, and marked histological alterations were observed in DSH rats. DSH rats showed obvious podocyte injury, peritubular capillary (PTC) loss, macrophage infiltration, and changes in apoptosis and cell proliferation. Moreover, Wnt/ß-catenin signaling was significantly activated in DSH rats. However, HCTZ administration attenuated these changes with decreased SBP. In addition, increased renal and urinary Wnt4 expression was detected with time in DSH rats and was closely correlated with histopathological alterations. Furthermore, these alterations were also confirmed by clinical study. In conclusion, the present study provides novel insight into the mechanisms related to PTC loss, macrophage infiltration and Wnt/ß-catenin signaling in SSHT-induced renal injury and fibrosis. Therefore, multi-target therapeutic strategies may be the most effective in preventing these pathological processes. Moreover, urinary Wnt4 may be a noninvasive biomarker for monitoring renal injury after hypertension.

Astragaloside IV inhibits microglia activation via glucocorticoid receptor mediated signaling pathway.

Inhibition of microglia activation may provide therapeutic treatment for many neurodegenerative diseases. Astragaloside IV (ASI) with anti-inflammatory properties has been tested as a therapeutic drug in clinical trials of China. However, the mechanism of ASI inhibiting neuroinflammation is unknown. In this study, we showed that ASI inhibited microglia activation both in vivo and in vitro. It could enhance glucocorticoid receptor (GR)-luciferase activity and facilitate GR nuclear translocation in microglial cells. Molecular docking and TR-FRET GR competitive binding experiments demonstrated that ASI could bind to GR in spite of relative low affinity. Meanwhile, ASI modulated GR-mediated signaling pathway, including dephosphorylation of PI3K, Akt, I κB and NF κB, therefore, decreased downstream production of proinflammatory mediators. Suppression of microglial BV-2 activation by ASI was abrogated by GR inhibitor, RU486 or GR siRNA. Similarly, RU486 counteracted the alleviative effect of ASI on microgliosis and neuronal injury in vivo. Our findings demonstrated that ASI inhibited microglia activation at least partially by activating the glucocorticoid pathway, suggesting its possible therapeutic potential for neuroinflammation in neurological diseases.

Wnt4 is a novel biomarker for the early detection of kidney tubular injury after ischemia/reperfusion injury.

Earlier intervention after acute kidney injury would promote better outcomes. Our previous study found that Wnt proteins are promptly upregulated after ischemic kidney injury. Thus, we assessed whether Wnt4 could be an early and sensitive biomarker of tubular injury. We subjected mice to bilateral ischemia/reperfusion injury (IRI). Kidney and urinary Wnt4 expression showed an early increase at 3 hours and increased further at 24 hours post-IRI and was closely correlated with histopathological alterations. Serum creatinine slightly increased at 6 hours, indicating that it was less sensitive than Wnt4 expression. These data were further confirmed by clinical study. Both kidney and urinary Wnt4 expression were significantly increased in patients diagnosed with biopsy-proven minimal change disease (MCD) with tubular injury, all of whom nevertheless had normal estimated glomerular filtration rate (eGFR) and serum creatinine. The increased Wnt4 expression also strongly correlated with histopathological alterations in these MCD patients. In conclusion, this is the first demonstration that increases in both kidney and urinary Wnt4 expression can be detected more sensitively and earlier than serum creatinine after kidney injury. In particular, urinary Wnt4 could be a potential noninvasive biomarker for the early detection of tubular injury.

[Reconstruction of the remnant penis: a 52-case report].

OBJECTIVE: To explore the effects of the combined method of abdominal axial flap transposition and penile elongation for the treatment of the remnant penis. METHODS: Fifty-two cases of the remnant penis treated with the combined method from 1984 April to February 2004 were analyzed retrospectively. Follow-up ranged from 0.5 to 20 years postoperatively. RESULTS: The lengths (both in normal and erectile conditions) and the circumferences of the penis gained after operation were (5.6 +/- 1.4) cm, (6.8 +/- 2.5 cm and (6.9 +/- 2.3) cm respectively. The recovery rates of the sensory function were 94.2% and 100% in the glans (immediately and 3 months after operation) and 32.7%, 51.9% and 75% in the flap area (3, 6 and 12 months postoperatively). The two-point distinguishing sense in the glans and the flap area was (5.1 +/- 0.9) mm and(7.9 +/- 1.3) mm 5 years after operation. Early complications included distant flap necrosis (3 cases), disruption of the wound (2 cases), part necrosis of the skin graft in the abdominal wall (2 cases) and poor contours occurred in 4 cases in the later period because of the thickness of the flaps. All of them were corrected with satisfactory results. CONCLUSION: The combined method of abdominal axial flap transposition and penile elongation was recommendable for the treatment of the remnant penis because of its positive effects and less complications.

Biofabrication of a PLGA-TCP-based porous bioactive bone substitute with sustained release of icaritin.

A phytomolecule, icaritin, has been identified and shown to be osteopromotive for the prevention of osteoporosis and osteonecrosis. This study aimed to produce a bioactive poly (l-lactide-co-glycolide)-tricalcium phosphate (PLGA-TCP)-based porous scaffold incorporating the osteopromotive phytomolecule icaritin, using a fine spinning technology. Both the structure and the composition of icaritin-releasing PLGA-TCP-based scaffolds were evaluated by scanning electron microscopy (SEM). The porosity was quantified by both water absorption and micro-computed tomography (micro-CT). The mechanical properties were evaluated using a compression test. In vitro release of icaritin from the PLGA-TCP scaffold was quantified by high-performance liquid chromatography (HPLC). The attachment, proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) on the composite scaffold were evaluated. Both an in vitro cytotoxicity test and an in vivo test via muscular implantation were conducted to confirm the scaffold's biocompatibility. The results showed that the PLGA-TCP-icaritin composite scaffold was porous, with interconnected macro- (about 480 µm) and micropores (2-15 µm). The mechanical properties of the PLGA-TCP-icaritin scaffold were comparable with those of the pure PLGA-TCP scaffold, yet was spinning direction-dependent. Icaritin content was detected in the medium and increased with time. The PLGA-TCP-icaritin scaffold facilitated the attachment, proliferation and osteogenic differentiation of BMSCs. In vitro cytotoxicity test and in vivo intramuscular implantation showed that the composite scaffold had no toxicity with good biocompatibility. In conclusion, an osteopromotive phytomolecule, icaritin, was successfully incorporated into PLGA-TCP to form an innovative porous composite scaffold with sustained release of osteopromotive icaritin, and this scaffold had good biocompatibility and osteopromotion, suggesting its potential for orthopaedic applications.

Angiopoietin-Like-4, a Potential Target of Tacrolimus, Predicts Earlier Podocyte Injury in Minimal Change Disease.

Podocyte injury plays central roles in proteinuria and kidney dysfunction, therefore, identifying specific biomarker to evaluate earlier podocyte injury is highly desirable. Podocyte-secreted angiopoietin-like-4 (Angptl4) mediates proteinuria in different types of podocytopathy. In the present study, we established an experimental minimal change disease (MCD) rat model, induced by adriamycin (ADR) and resulted in definite podocyte injury, to identify the dynamic changes in Angptl4 expression. We also investigated the direct effects of tacrolimus on Angptl4 and podocyte repair. We determined that the glomerular Angptl4 expression was rapidly upregulated and reached a peak earlier than desmin, an injured podocyte marker, in the ADR rats. Furthermore, this upregulation occurred prior to heavy proteinuria and was accompanied by increased urinary Angptl4. We observed that the Angptl4 upregulation occurred only when podocyte was mainly damaged since we didn't observe little Angptl4 upregulation in MsPGN patients. In addition, we observed the glomerular Angptl4 mainly located in injured podocytes rather than normal podocytes. Moreover, we found that tacrolimus treatment significantly promoted podocyte repair and reduced glomerular and urinary Angptl4 expression at an earlier stage with a significant serum Angptl4 upregulation. And similar results were confirmed in MCD patients. In conclusion, this study represents the first investigation to demonstrate that Angptl4 can predict podocyte injury at earlier stages in MCD and the identification of earlier podocyte injury biomarkers could facilitate the prompt diagnosis and treatment of patients with podocytopathy, as well as determination of the prognosis and treatment efficacy in these diseases.

Upregulation of podocyte-secreted angiopoietin-like-4 in diabetic nephropathy.

Podocyte injury plays a key role in the development of diabetic nephropathy (DN). Understanding the changes in podocyte structure and function in diabetes mellitus may lead to novel diagnostic tools and treatment strategies for DN. Albuminuria, histological alterations, and podocyte injury were detected at different time points in streptozotocin (STZ)-induced diabetic rats. Increased urinary albumin-to-creatinine ratios (ACR) and podocyte injury were significantly observed 4 weeks post-STZ injection. We determined the glomerular expression and distribution of angiopoietin-like 4 (Angptl4) by immunofluorescence and real-time PCR. Glomerular Angptl4 expression was mostly colocalized with synaptopodin, a podocyte marker, with substantial additional overlap with the glomerular basement membrane (GBM). This finding indicated that Angptl4 might be primarily secreted by podocytes and moved toward the GBM. Moreover, we observed by Western blot analysis and ELISA that the urinary Angptl4 level was gradually upregulated in both STZ-induced rats and diabetic patients with microalbuminuria and macroalbuminuria. We further found that the increased glomerular Angptl4 expression was closely related to the urinary ACR level and podocyte injury. In addition, the urinary Angptl4 expression was closely associated with albuminuria in the rats and patients with DN. This study is the first to show that podocyte-secreted Angptl4 is upregulated in DN and can be detected in urine. Angptl4 might function as a podocyte injury marker and could be a potential and novel diagnostic and therapeutic biomarker for DN.

Src inhibitor reduces permeability without disturbing vascularization and prevents bone destruction in steroid-associated osteonecrotic lesions in rabbits.

To examine the therapeutic effect of Src inhibitor on the VEGF mediating vascular hyperpermeability and bone destruction within steroid-associated osteonecrotic lesions in rabbits. Rabbits with high risk for progress to destructive repair in steroid-associated osteonecrosis were selected according to our published protocol. The selected rabbits were systemically administrated with either Anti-VEGF antibody (Anti-VEGF Group) or Src inhibitor (Src-Inhibition Group) or VEGF (VEGF-Supplement Group) or a combination of VEGF and Src inhibitor (Supplement &Inhibition Group) or control vehicle (Control Group) for 4 weeks. At 0, 2 and 4 weeks after administration, in vivo dynamic MRI, micro-CT based-angiography, histomorphometry and immunoblotting were employed to evaluate the vascular and skeletal events in different groups. The incidence of the destructive repair in the Anti-VEGF Group, Src-Inhibition Group and Supplement &Inhibition Group was all significantly lower than that in the Control Group. The angiogenesis was promoted in VEGF-Supplement Group, Src-Inhibition Group and Supplement &Inhibition Group, while the hyperpermeability was inhibited in Anti-VEGF Group, Src-Inhibition Group and Supplement &Inhibition Group. The trabecular structure was improved in Src-Inhibition Group and Supplement &Inhibition Group. Src inhibitor could reduce permeability without disturbing vascularization and prevent destructive repair in steroid-associated osteonecrosis.

Community-based survey of HCV and HIV coinfection in injection drug abusers in Sichuan Province of China.

AIM: To investigate the prevalence and risk factors of HCV/HIV coinfection in injection drug abusers (IDAs) in Lianshan Yi Autonomous Prefecture of Sichuan province, China. METHODS: From November 8, 2002 to November 29, 2002, a community-based survey was conducted to investigate the demographic characteristics, patterns of shared injectors devices and sexual behaviors in IDAs. Blood samples were also collected to test HCV and HIV infection. A total of 379 subjects were recruited in the study through community outreach and peer recruiting methods. RESULTS: Of the 379 IDAs, the HCV prevalence and HIV prevalence were 71.0% and 11.3%, respectively, and HCV/HIV coinfection was 11.3%. HCV infection was found in 100% and 67.3% of HIV-positive and HIV-negative IDAs, respectively. HIV prevalence was 16.0% in HCV positive IDAs while none of the HCV negative IDAs was positive for HIV. Ethnicity, shared needles or syringes and cotton in the past 3 mo and syphilis infection were associated with HCV/HIV coinfection shown by univariate analysis using chi-square test. Multivariate logistic regression analysis showed that shared needles or syringes in the past 3 mo (Odds ratio=3.121, 95% CI: 1.278-7.617, P<0.05) and syphilis infection (Odds ratio=2.914, 95% CI: 1.327-6.398, P<0.01) were significantly associated with HCV infection. No statistically significant association was found in univariate analysis between sexual behaviors and HCV/HIV coinfection. CONCLUSION: Shared needles and syringes in the past 3 mo and syphilis infection were significantly associated with HCV infection. Further sero-epidemiological prospective cohort studies should be conducted to clarify the impact of syphilis and high risk sexual behaviors on HCV transmission through unprotected sexual intercourse.