[Expression of TGF-beta and hepatocyte growth factor in kidney tissues of children with primary focal segmental glomerular sclerosis]

OBJECTIVE

To study the expression of transforming growth factor-beta (TGF-beta) and hepatocyte growth factor (HGF) in kidney tissues of children with primary focal segmental glomerular sclerosis (FSGS) and the possible role of the two growth factors in the development of FSGS.

METHODS

Kidney specimens were obtained from 33 children with primary FSGS and 7 children with isolated haematuria but without FSGS (control group). Of the 33 children with primary FSGS, 6 children had no renal tubule interstitial pathological damage (Experimental I group) and 27 children had renal tubule interstitial pathological damage (Experimental II group). Expression of TGF-beta and HGF in kidney tissues was ascertained by the immunohistochemical method.

RESULTS

TGF-beta and HGF were expressed in the three groups, but there were significant differences among the three groups. The expression of TGF-beta and HGF in the two experiment groups increased significantly compared with that in the control group. The Experimental II group had increased TGF-beta expression but a significantly decreased HGF expression compared with the Experimental I group. The index of tubule interstitial pathological changes was positively correlated with the TGF-beta expression (r=0.763, P<0.01), but negatively correlated with the HGF expression (r=-0.461, P<0.05) in the Experimental II group. There was a negative correlation between TGF-beta and HGF expression in children with primary FSGS (r=-0.425, P<0.05).

CONCLUSIONS

The expression of TGF-beta and HGF in kidney tissues is increased in children with primary FSGS. TGF-beta might be a fibrogenic factor and HGF might be an anti-fibrotic factor in the kidney in primary FSGS.

Bradykinin B(1) receptor antagonist R954 inhibits eosinophil activation/proliferation/migration and increases TGF-beta and VEGF in a murine model of asthma

In the present study the effects of bradykinin receptor antagonists were investigated in a murine model of asthma using BALB/c mice immunized with ovalbumin/alum and challenged twice with aerosolized ovalbumin. Twenty four hours later eosinophil proliferation in the bone marrow, activation (lipid bodies formation), migration to lung parenchyma and airways and the contents of the pro-angiogenic and pro-fibrotic cytokines TGF-beta and VEGF were determined. The antagonists of the constitutive B(2) (HOE 140) and inducible B(1) (R954) receptors were administered intraperitoneally 30min before each challenge. In sensitized mice, the antigen challenge induced eosinophil proliferation in the bone marrow, their migration into the lungs and increased the number of lipid bodies in these cells. These events were reduced by treatment of the mice with the B(1) receptor antagonist. The B(2) antagonist increased the number of eosinophils and lipid bodies in the airways without affecting eosinophil counts in the other compartments. After challenge the airway levels of VEGF and TGF-beta significantly increased and the B(1) receptor antagonist caused a further increase. By immunohistochemistry techniques TGF-beta was found to be expressed in the muscular layer of small blood vessels and VEGF in bronchial epithelial cells. The B(1) receptors were expressed in the endothelial cells. These results showed that in a murine model of asthma the B(1) receptor antagonist has an inhibitory effect on eosinophils in selected compartments and increases the production of cytokines involved in tissue repair. It remains to be determined whether this effects of the B(1) antagonist would modify the progression of the allergic inflammation towards resolution or rather towards fibrosis.

Physical instability, aggregation and conformational changes of recombinant human bone morphogenetic protein-2 (rhBMP-2)

The influence of two different pH values on the physical stability of recombinant human bone morphogenetic protein-2 (rhBMP-2) in aqueous solution was evaluated in the present work. RhBMP-2 in solution at pH 4.5 or 6.5 was characterized by intrinsic and extrinsic (Nile Red and 1,8-ANS) fluorescence spectroscopy, 90 degrees light-scattering and transmission electron microscopy (TEM). Compared to the pH 4.5 solution, rhBMP-2 at pH 6.5 had (i) a stronger intrinsic fluorescence intensity, (ii) a longer fluorescence lifetime, (iii) a stronger 90 degrees light-scattering intensity, (iv) a stronger Nile Red fluorescence intensity, (v) a higher Nile Red fluorescence anisotropy, (vi) a lower 1,8-ANS fluorescence intensity, (vii) a higher 1,8-ANS fluorescence anisotropy and (viii) a longer 1,8-ANS fluorescence lifetime. Electron microscopy showed that rhBMP-2 at pH 4.5 contained aggregates of about 100 nm in diameter. More and larger protein aggregates (0.1-2 microm) were observed in solution at pH 6.5. Taken together, these results indicate conformational changes and increased aggregation of rhBMP-2 at pH 6.5 compared to pH 4.5, demonstrating a strong influence of pH on rhBMP-2 physical stability. These observations must be considered when developing a delivery system for rhBMP-2.

Milk-derived transforming growth factor-beta and the infant immune response

Breast milk cytokines have the potential to regulate the immune response to food antigens in infants. Cytokines are present in all mammalian milks and are capable of inhibiting excess inflammation and modulating epithelial proliferation. There are a range of candidate cytokines in milk such as transforming growth factor-beta (TGF-beta), the major cytokine present, and interleukin-10, which play a role in immune regulation in the developing infant. This article will be a review of the current literature with regard to TGF-beta in infant immune development. Our data on supplementation of formula with rTGF-beta2 will be discussed in view of the current literature. Oral antigen exposure also plays an important role in priming the developing immune response. The influence of early introduction of oral beta-lactoglobulin in allergy prone rat pups will also be discussed.

Anterior diffuse retinoblastoma: mutational analysis and immunofluorescence staining

Retinoblastoma is the most common primary intraocular tumor of childhood and may be heritable or occur sporadically. Anterior diffuse retinoblastoma is an uncommon variant that is thought to be sporadic. We describe a child with anterior diffuse retinoblastoma who presented with a pseudohypopyon. Genetic analysis showed a germline mutation of the RB1 allele that is potentially heritable. Immunofluorescence staining was positive for transforming growth factor beta and for vascular endothelial growth factor and negative for inducible nitric oxide synthase and for hypoxia inducible factor alpha in the tumor seeds, indicating acquisition of nonischemia-mediated survival factors of the tumor seeds in the aqueous humor.

Role of Interleukins and Transforming Growth Factor-β in Chronic Rhinosinusitis and Nasal Polyposis

OBJECTIVES

To determine the role of interleukin (IL)-4, IL-4 receptor (R), IL-6, IL-8, IL-11, and transforming growth factor (TGF)-beta in chronic rhinosinusitis (CRS) and chronic rhinosinusitis with nasal polyposis (CRS/NP).

METHODS

Sinus tissue from patients undergoing endoscopic sinus surgery for CRS and CRS/NP was collected. Sinus tissue was then analyzed using reverse-transcription polymerase chain reaction (RT-PCR) to detect transcription of IL-4R, IL-6, IL-8, and IL-11. Sinus tissue samples were also cultured in vitro, treated with IL-4 for 24 hours, and real-time PCR was used to quantify the transcription of TGF-beta.

RESULTS

Twenty patients were evaluated, 9 with CRS/NP and 11 with CRS alone. The mean age was 43 (20-74) years, with 13 females and 7 males. IL-4R, IL-6, IL-8, and IL-11 were identified by RT-PCR in all 20 patients. The transcription of TGF-beta was found to be 3.2 times greater in patients with CRS/NP than in patients with CRS alone (P = .047).

CONCLUSION

IL-6, IL-8, and IL-11 are nonspecific markers of sinus inflammation being transcribed in patients with CRS and patients with CRS/NP. However, patients with CRS/NP demonstrate increased transcription of TGF-beta in response to IL-4 treatment, suggesting an IL-4 mediated mechanism for stromal proliferation in the formation of nasal polyposis.

Simultaneous immunophenotypical assessment of troponin and extracellular matrix molecules in myocardium of patients with sudden cardiac death

In patients with sudden unexpected cardiac death, there is a relationship between the interstitial fibrosis of the myocardium and matrix molecules with a role in global remodeling of the cardiac stroma. Tissue samples of left ventricular myocardium from 17 middle-aged patients with sudden cardiac death, following acute or chronic ischemic cardio(myo)pathies, were analyzed using standard HE stain and the indirect tristadial ABC peroxidase immunohistochemical method for a panel of four antibodies involved in the dynamic remodeling of extracellular matrix: matrix metalloproteinase 9 (MMP9), tenascin X (Tn-X), TGF-b, CD54 (ICAM-1), together with simultaneously assessment of troponin in myocardic fibers. The most sensitive reaction was noticed for ICAM-1 in 71% of cases, followed by MMP9 in 59% of cases and TGF-b in 47% of cases (with great specificity for capillary vessels), in the extracellular matrix of the residual cardiomyocytes. A direct correlation, statistically significant was recorded between troponin and MMP9 (r = 0.65, p = 0.01), troponin and ICAM-1 (r = 0.31, p = 0.02), respectively ICAM-1 and tenascin (r = 0.72, p = 0.01). The extensive expression of ICAM-1 in the extracellular matrix from the perilesional area probably plays a role in the stimulation of new developing adhesion substrates between residual cells and adjacent stroma, while the over expression of troponin in the residual cardiomyocytes is accompanied by a high expression of MMP9 in the myocardic interstitium, with heterogeneous remodeling of the ventricular stroma. The simultaneous IHC expression of tenascin and ICAM-1 suggests a colocalization required for the nerve sprouting in the residual myocardium and for developing new focal cell-matrix adhesion contacts.

Early morphofunctional response of contact tissue after intraosal implantation in rabbit jaw of pure synthetic hydroxyapatite (HAp) bioceramic materials and HAp saturated with lidocaine

PURPOSE

The aim of this study was to evaluate early morphofunctional response of contact tissue to pure and saturated with lidocaine porous synthetic HAp ceramic implants inserted in holes of rabbit upper jaw.

MATERIALS AND METHODS

Pure and saturated with lidocaine cylinders of porous HAp ceramics produced at Biomaterials R&D Laboratory of Riga Technical University were inserted into edentulous part of the upper jaw of 12 New Zealand male rabbits. After two weeks, blocks of soft tissue and bone were taken out. The sections done with EXACT Grunding system and from paraffin blocks were stained with haematoxylin/eosin and by use of biotin-streptavidin immunohistochemistry for transforming growth factor beta1 (TGFbeta1), fibroblast growth factor receptor 1 (FGFR1), interleukin 10 (IL10). Apoptosis was detected by TUNEL method.

RESULTS

TGFbeta1 was equally expressed in the bone around HAp implants saturated with lidocaine and without lidocaine, while control sections did not show any expression of TGFbeta. In contacting bone tissue to pure HAp and HAp saturated with lidocaine as well in controls rich expression of FGFR1 was observed. In soft tissue of experimental samples also rich expression of FGFR1 was observed, although it was weak in control samples. IL10 had rich expression in all samples. The mean number of apoptotic cells was higher in samples with pure HAp, slightly decreased in samples HAp with lidocaine and significantly lower in controls.

CONCLUSIONS

The expression of TGF beta1 confirms osteoinductive activity of HAp. Contact soft tissue to HAp showed rich FGFR1 expression, and weak in controls suggesting higher plasticity of connective tissue to implants in comparison with supportive tissue. Slightly lower apoptosis in samples of HAp with lidocaine gives evidence of indistinct influence of saturated with lidocaine HAp implants on development of programmed cell death.

Intermittent Pressure-Loading Increases Transforming Growth Factor-Beta-1 Secretion from Renal Tubular Epithelial Cells: In vitro Vesicoureteral Reflux Model

BACKGROUND

To investigate the effect of hydrodynamic pressure mimicking vesicoureteral reflux on renal tubular epithelial cells in vitro, we constructed an intermittent pressure-loading (IPL) model of Madin-Darby canine kidney (MDCK) cells.

MATERIALS AND METHODS

Three grades of pressure were loaded onto the MDCK cells intermittently. The concentration of cytokines in the supernatant, the amount of the protein and its mRNA in the MDCK cells were studied, respectively.

RESULTS

After 24 h, the concentration of transforming growth factor-beta1 (TGF-beta1) increased under intense IPL conditions (100 and 200 cm H2O) in the 15-min IPL group (p<0.05, p<0.01). The amount of cellular level of TGF-beta1 protein and its mRNA did not show any significant increase within 24 h under the present conditions. The concentration of monocyte chemoattractant peptide-1 (MCP-1) was not significantly different from that of the control.

CONCLUSION

These data suggest that the early TGF-beta1 secretion phenomenon without change in gene expression is the case in the renal tubular epithelial cells under certain intermittent pressure-loading conditions.

Osteoprogenitor differentiation is not affected by immunomodulatory thalidomide analogs but is promoted by low bortezomib concentration, while both agents suppress osteoclast differentiation

We investigated the effects of bortezomib (PS-341) and immunomodulatory thalidomide analogs (immunomodulatory compounds; CC-4047, CC-6032, and CC-5013, or lenalidomide) on osteoblast and osteoclast differentiation in vitro using human mesenchymal stem cells (hMSC) to commit to osteoprogenitor cells and peripheral blood mononuclear cells (PBMCs) isolated from healthy donors, respectively. First, the concentration of bortezomib for an anti-myeloma effect was more than 1.0 nM in myeloma cells of multiple myeloma (MM) patients and more than 2.5 nM in myeloma cell lines. In contrast, anti-myeloma effects of immunomodulatory compounds on myeloma cells differed among myeloma cells and these compounds themselves. Subsequently, these agents (bortezomib; 0.5-5.0 nM, immunomodulatory compounds; 10 microM) were added to the osteoprogenitor cell culture media or the media for osteoclast differentiation. Low bortezomib concentrations (0.5 and 1.0 nM) increased ALP activity, and the delayed addition of bortezomib further increased ALP activity. Mineralized nodular formation with <2.5 nM bortezomib was not impaired. BMP2 expression on osteoprogenitor cells was found to increase in a time-dependent manner irrespective of treatment with bortezomib. On the other hand, the anti-osteoclast effect with low bortezomib concentration (< or =2.5 nM) depended on MM patients. In contrast, immunomodulatory compounds at 10 microM showed an anti-osteoclast effect without cytotoxicity to osteoblast differentiation, at which dose myeloma cells underwent apoptosis. These findings might improve the treatment strategy for MM patients without damaging BM stromal cells by combining bortezomib with immunomodulatory compounds.

Osteogenic potential of the human bone morphogenetic protein 2 gene activated nanobone putty

BACKGROUND

Nanobone putty is an injectable and bioresorbable bone substitute. The neutral-pH putty resembles hard bone tissue, does not contain polymers or plasticizers, and is self-setting and nearly isothermic, properties which are helpful for the adhesion, proliferation, and function of bone cells. The aim of this study was to investigate the osteogenic potential of human bone morphogenetic protein 2 (hBMP2) gene activated nanobone putty in inducing ectopic bone formation, and the effects of the hBMP2 gene activated nanobone putty on repairing bone defects.

METHODS

Twenty four Kunming mice were randomly divided into two groups. The nanobone putty + hBMP2 plasmid was injected into the right thigh muscle pouches of the mice (experiment side). The nanobone putty + blank plasmid or nanobone putty was injected into the left thigh muscle pouches of the group 1 (control side 1) or group 2 (control side 2), respectively. The effects of ectopic bone formation were evaluated by radiography, histology, and molecular biology analysis at 2 and 4 weeks after operation. Bilateral 15 mm radial defects were made in forty-eight rabbits. These rabbits were randomly divided into three groups: Group A, nanobone putty + hBMP2 plasmid; Group B, putty + blank plasmid; Group C, nanobone putty only. Six rabbits with left radial defects served as blank controls. The effect of bone repairing was evaluated by radiography, histology, molecular biology, and biomechanical analysis at 4, 8, and 12 weeks after operation.

RESULTS

The tissue from the experimental side of the mice expressed hBMP2. Obvious cartilage and island-distributed immature bone formation in implants of the experiment side were observed at 2 weeks after operation, and massive mature bone observed at 4 weeks. No bone formation was observed in the control side of the mice. The ALP activity in the experiment side of the mice was higher than that in the control side. The tissue of Group A rabbits expressed hBMP2 protein and higher ALP level. The new bone formation rate and antibending strength of group A was significantly higher than those of group B and C. The defects in blank control were not healed.

CONCLUSIONS

The hBMP2 gene activated nanobone putty exhibited osteoinductive ability, and had a better bone defect repair capability than that of nanobone putty only.

BIGH3 is overexpressed in clear cell renal cell carcinoma

To identify new target marker genes in renal cell carcinoma (RCC), we compared the gene expression profiles of clear cell RCC (cc-RCC) and normal kidney tissue using serial analysis of gene expression. Our results revealed that the transforming growth factor beta induced 68 kDa protein (TGF-betaI: beta ig-h3 (BIGH3), plasminogen activator inhibitor-1 (PAI-1) and transforming growth factor beta1 (TGF-beta1) genes are up-regulated in cc-RCC. To further assess the role of BIGH3 in RCC, we investigated the mRNA expression levels of BIGH3, TGFbeta1, PAI-1 and also of TGF-beta1 related genes in 53 RCC and 30 normal kidney tissues by quantitative real-time RT-PCR (QRT-PCR). We further determined the BIGH3 protein levels in 52 cc-RCC paraffin-embedded tissue samples by immunohistochemistry. BIGH3 mRNA was found to be highly overexpressed in cc-RCC compared with normal tissues with an average ratio of 27. The mRNA levels of TGF-beta1 and PAI-1 were also detected at significantly elevated levels in these cancers. Immunohistochemical analysis of BIGH3 also revealed strong staining in the majority of the cc-RCC samples. In addition, the up-regulation of BIGH3 and PAI-1 was found to correlate with the clinicopathological parameters associated with a poorer patient outcome, whereas TGF-beta1 expression was determined to be unrelated to cancer progression. Strong BIGH3 staining thus tended to be associated with a poor prognosis. BIGH3 was also induced in some RCC cell lines by TGF-beta1 stimulation and this correlated well with PAI-1 up-regulation, suggesting that these enhancements are regulated by a similar mechanism in these tumors.

Muscle wasting in diabetic and in tumor-bearing rats: role of oxidative stress

Cachexia is a debilitating syndrome characterized by body weight loss, muscle wasting, and anemia. Muscle wasting results from an altered balance between protein synthesis and degradation rates. Reactive oxygen species are indicated as crucial players in the onset of muscle protein hypercatabolism by upregulating elements of the ubiquitin-proteasome pathway. The present study has been aimed at evaluating comparatively the involvement of oxidative stress in the pathogenesis of skeletal muscle wasting in two different experimental models: rats rendered hyperglycemic by treatment with streptozotocin and rats bearing the Yoshida AH-130 ascites hepatoma. For this purpose, both tumor bearers and diabetic animals have been treated with dehydroepiandrosterone (DHEA), a multifunctional steroid endowed with multitargeted antioxidant properties. We show that diabetic rats and AH-130 rats share several features, hypoinsulinemia, occurrence of oxidative stress, and positive response to DHEA administration, although the extent of the effects of DHEA largely differs between diabetic animals and tumor-bearing rats. The hypercatabolism, evaluated in terms of proteasome activity and expression of atrogin-1 and MuRF1, is activated in AH-130 rats, whereas it is lacking in streptozotocin-treated rats. Moreover, we demonstrate that the role of oxidative stress can interfere with muscle wasting through different mechanisms, not necessarily involving NF-kappaB activation. In conclusion, the present results show that, although skeletal muscle wasting occurs in both diabetic rats and tumor-host rats, the underlying mechanisms are different. Moreover, despite oxidative stress being detectable in both experimental models, its contribution to muscle wasting is not comparable.

[Influence of human bone marrow-derived mesenchymal stem cells on the lung of newborn rats damaged by hyperoxia]

OBJECTIVE

To evaluate whether human mesenchymal stem cells (hMSCs) administration alter the clinical course of hyperoxia-induced lung injury.

METHODS

hMSCs were obtained from bone marrow aspirates from healthy donors after informed consent was signed, hMSCs were separated, cultured, amplified, identified and labeled with BrdU. For BrdU labeling, a sterile stock solution was added to the culture medium 48 h before the end of culture, at a final concentration of 10 micromol/L. Thirty-two 3-day old SD rats from four litters were randomly divided into four groups, as hyperoxia exposed + hMSC group (A), air-exposed + hMSC group (B), hyperoxia exposed group (C), and air-exposed group (D). The rats from the group A and the group C were placed in a sealed Plexiglas chamber with a minimal in- and outflow, providing six to seven exchanges per hour of the chamber volume and maintaining O2 levels above 95%, while the rats in the group B and the group D were only exposed to room air. Seven days later, all of them were taken out of the chamber, rats in the group A and B were injected intraperitoneally with hMSCs (1 x 10(5) in 50 microl of PBS) immediately, while the rats in the group C and D were only treated with 50 microl of PBS 3 days later. All the animals were sacrificed by an injection of sodium pentobarbital (120 mg/kg), perfused with cold 0.9% NaCl, and the left lungs were removed, the upper lobes of which were ground as tissue homogenates and used for ELISA, while the inferior lobes were stored at -70 degrees C until use for RT-PCR. The right lungs were fixed in situ for 2 h by the intratracheal instillation with 10% neutral formalin and then postfixed for 24 h. Sagittal sections (4-microm) of paraffin-embedded middle lobe and upper lobe of the right lung were used for immunohistochemistry and histology, respectively.

RESULTS

(1) There was a significant difference in the value of RAC (raditive alveoli coant) among the 4 groups (11.145 +/- 1.331, 13.941 +/- 0.985, 9.595 +/- 0.672, 14.819 +/- 1.080, F = 43.234, P = 0.000). RAC in group A and C were significantly reduced compared with subjects in group D (P < 0.05, P < 0.05); and there was also a significant difference between group A and group C (P < 0.05), but not between group B and D subjects (P > 0.05). (2) There were significant differences in the levels of both TNFalpha and TGFbeta(1) in the homogenate of lungs among the 4 groups (142.933 +/- 24.017, 79.033 +/- 11.573, 224.088 +/- 41.915, 76.500 +/- 10.373, F = 59.970, P = 0.000; 1726.484 +/- 91.086, 1530.359 +/- 173.441, 2047.717 +/- 152.057, 1515.777 +/- 131.049, F = 24.977, P = 0.000). The levels of TNFalpha and TGFbeta1 were significantly elevated in both group A and group C when compared with subjects in group D (P < 0.05 for both). Concentrations of TNFalpha and TGFbeta1 were both significantly decreased in group A versus group C (P < 0.05 for both). There was no significant difference between group B and D subjects in the fields of TNFalpha and TGFbeta(1) (P > 0.05 for both). (3) BrdU-labelled cells were observed at alveolar wall and bronchioles in both group A and group B, and there was a significant difference in BrdU-labeled cells between two groups (0.230 +/- 0.026, 0.190 +/- 0.015; t = 3.769, P = 0.002), but none was found in group C and group D. Electrophoresis of the PCR products showed a 224 bp band, specific for Alu mRNA, in 7 of 8 rats of group A and 5 of 8 rats of group B, respectively, but no such band was found in group C and group D.

CONCLUSION

hMSCs administered by intraperitoneal injection could be implanted in the lungs of newborn rats, and they could effectively protect the rats against damage to the lungs caused by hyperoxia.

Barx1, growth factors and apoptosis in facial tissue of children with clefts

OBJECTIVE

Clefts of lip and palate belong to the most common birth defects worldwide. Growth factors and genes play an important role in tissue growth, differentiation and induction and upregulation of growth factors, apoptosis and matrix metalloproteinases might be involved in pathogenesis of facial clefts. The aim of this study was investigation of palate tissue in children with unilateral cleft lip palate for detection of local tissue growth factors, barx1 and apoptosis.

MATERIALS AND METHODS

We investigated soft and hard palate tissue from 36 children with complete unilateral cleft lip and palate from cleft area.14 children were in age before and primary dentition, but 22 children were in mixed dentition period. We examined the localization of barx1, FGFR1, NGFR, TGFbeta, BMP2/4, MMP2, PGP 9,5 by immunohistochemistry. TUNEL method was performed for detection of apoptotic cells.

RESULTS

Abundance of FGFR1 positive cells was seen almost in all cases. FGFR richly stained cells of soft and hard palate tissue. Abundance of NGFR positive cells was detected in basal epithelium, hair follicles, nerve fibers in wall of blood vessels and subepithelium, and was more often seen in children before mixed dentition. TGFbeta has showed intensive expression in epithelium, cartilage and bone in both dentition ages. Chondrocytes, fibroblasts and macrophages expressed MMP2 predominant before mixed dentition. Regional expression of barx1 was observed in epithelium before the mixed dentition, while during mixed dentition gene appeared in hyaline cartilage. TUNEL discovered apoptosis in both dentition ages.

CONCLUSIONS

FGFR1 and TGFbeta are main tissue stimulating growth factors in both dentition ages. Expression of barx1 appears in cleft lip palate affected structures mainly in mixed dentition ages. NGFR and neuropeptides-containing structures are mainly characteristic in cleft tissue before mixed dentition. Distribution of genes, GF and apoptosis seem to correlate rather with dentition age than to type of CLP.

Polymer angiogenic factor carrier. Part I. Chitosan-alginate membrane as carrier PDGF-AB and TGF-beta

Microcrystalline chitosan (MCCh) characterise by many valuable features, including biocompatibility, antibacterial, fungicidal and high adhesive properties, high water retention value (WRV) factor, potent sorption, high bioactivity, biodegradability, ability to create membranes directly out of water suspensions. This biopolymer due to its biodegradability and safety in application no cytotoxic or immune interaction was assessed as a very effective haemostatic factor. MCCh with such properties form useful initial material for biological bandages; it can be used in surgery as growth factor carrier. Biodegradable mambranes are applied in surgery for guided tissue regeneration, what contributed to make the manufacturing technology of modified membranes out of microcrystalline chitosan. Peformed research was to show how certain angiogenic factors are released--platelet derived angiogenic factor (PDAF-AB) and transforming factor beta (TGF-beta) from doubled-layered alginate-chitosane membrane which was already used in dental surgery. Assessment of angiogenic factors release (PDGF-AB and TGF-beta) from polymer base may become helpful in choosing the right carrier for growth factors.

Immunohistochemical evidence of BMP-2, -4 and -7 activity in otospongiosis

CONCLUSION

This study is the first to show that bone morphogenetic proteins (BMP)-2, -4 and -7 play a role in active phase otosclerotic bone remodelling (otospongiosis).

OBJECTIVES

The role of BMPs in various tissue growth and repair mechanisms is an ongoing topic in the literature. BMP-2, -4 and -7 are known to be of major importance in bone formation and repair. Their role in otosclerotic bone transformation has not been analysed previously. The main goal of this study was to perform an immunohistological analysis of BMP-2, -4 and -7 in otoclerosis.

MATERIALS AND METHODS

Parts of the stapedial footplates, collected during partial stapedectomies in 30 patients with clinical otosclerosis, were analysed for histological otosclerotic lesions after staining haematoxylin and eosin. Immunohistochemical analysis was performed using polyclonal IgG antibodies for BMP-2, -4 and -7, as well as biotinylated secondary antibodies, avidin-biotin-peroxidase complex reaction and alkaline phosphatase staining.

RESULTS

In all, 14 specimens contained otosclerosis; 3 of these were otospongiotic, 8 fibrotic, 2 sclerotic and 1 had both sclerotic and fibrotic lesions. Thus in total 14/30 specimens (47%) showed histological otosclerosis. Only the multiple osteoblasts and osteoclasts in those specimens exhibiting an otospongiotic phase showed distinct immunochemical staining for BMP-2, -4 and -7.

Multitiered health assessment of Atlantic menhaden in the Pamlico River, North Carolina

During the fall of 2001 and 2002, Atlantic menhaden Brevoortia tyrannus were collected from several creeks in the Pamlico River, North Carolina, to investigate recent fish kills and ulcerative skin lesions. High skin lesion prevalence (>50%) was associated with the Atlantic menhaden kills in fall 2001, whereas there were no fish kills in fall 2002 and skin lesion prevalence was lower (< or =50%). Indicators of tissue damage (histopathological analyses of gills, heart, liver, intestine, and anterior kidney), body condition (liver somatic index), and immune status (transforming growth factor-beta [TGF-beta] messenger RNA [mRNA] production, hematology, plasma chemistry, and splenosomatic index) were compared between Atlantic menhaden with and without ulcerative skin lesions in fall. Atlantic menhaden with ulcerative skin lesions had significantly higher liver somatic indices, neutrophil and monocyte percentages, and splenic mononuclear cell TGF-beta mRNA levels than did fish without lesions. Hematocrit values, plasma protein, and Ca concentrations were significantly lower in fish with ulcerative skin lesions than in those without. The indicators used in this study at multiple levels of biological organization have provided valuable baseline data for understanding the health status of lesioned and nonlesioned Atlantic menhaden in the Pamlico River.

The expression of transforming growth factor beta in pregnant rat myometrium is hormone and stretch dependent

From a quiescent state in early pregnancy to a highly contractile state in labor, the myometrium displays tremendous growth and remodeling. We hypothesize that the transforming growth factor beta (TGFbeta) system is involved in the differentiation of pregnant myometrium throughout gestation and labor. Furthermore, we propose that during pregnancy the mechanical and hormonal stimuli play a role in regulating myometrial TGFbetas. The expression of TGFbeta1-3 mRNAs and proteins was examined by real-time PCR, Western immunoblot, and localized with immunohistochemistry in the rat uterus throughout pregnancy and labor. Tgfbeta1-3 genes were expressed differentially in pregnant myometrium. Tgfbeta2 gene was not affected by pregnancy, whereas the Tgfbeta1 gene showed a threefold increase during the second half of gestation. In contrast, we observed a dramatic bimodal change in Tgfbeta3 gene expression throughout pregnancy. Tgfbeta3 mRNA levels first transiently increased at mid-gestation (11-fold on day 14) and later at term (45-fold at labor, day 23). Protein expression levels paralleled the changes in mRNA. Treatment of pregnant rats with the progesterone (P4) receptor antagonist RU486 induced premature labor on day 19 and increased Tgfbeta3 mRNA, whereas artificial maintenance of elevated P4 levels at late gestation (days 20-23) caused a significant decrease in the expression of Tgfbeta3 gene. In addition, Tgfbeta3 was up-regulated specifically in the gravid horn of unilaterally pregnant rats subjected to a passive biological stretch imposed by the growing fetuses, but not in the empty horn. Collectively, these data indicate that the TGFbeta family contributes in the regulation of myometrial activation at term integrating mechanical and endocrine signals for successful labor contraction.

Spatiotemporal expression of decorin and myostatin during rat skeletal muscle development

Decorin, a small leucine-rich proteoglycans, plays an important role in tissue morphogenesis through the regulation of collagen fibrillogenesis and the modulation of some growth factors. Our recent study has shown that decorin binds to myostatin, a negative regulator of skeletal muscle mass, and modulates its inhibitory action to myogenic cell growth in vitro. However, it still remains unclear whether decorin binds to myostatin in vivo during the development of skeletal muscle. To clarify this, we investigated the spatiotemporal expression of decorin and myostatin in rat skeletal muscle by RT-PCR and immunohistochemistry. Decorin mRNA abundance in fetal skeletal muscle was significantly higher than those in neonates and adults (P<0.05). Decorin mRNA expression decreased drastically at birth, and thereafter gradually up to 9 weeks of age. The mRNA expression pattern of myostatin was quite similar to that of decorin during prenatal and postnatal development of rat skeletal muscle. Immunohistochemical analysis demonstrated that myostatin was located in the muscle fibers, and that decorin was located in the periphery of muscle fibers in fetal rat skeletal muscle. Taken together with our previous data, these results suggest that decorin binds myostatin and sequesters it in the ECM during the development of rat skeletal.

Hypothesis: myostatin is a mediator of cardiac cachexia

Myostatin is a recently described negative regulator of skeletal muscle mass. This paper hypothesizes a role for this system in cardiac cachexia and insulin resistance and osteoporosis associated with advanced heart failure.

Follistatin rescues the inhibitory effect of activin A on the differentiation of bovine preadipocyte

We investigated the effect of activin A and follistatin on the differentiation of bovine preadipocytes. Stromal-vascular (SV) cells containing preadipocytes were prepared from perirenal adipose tissue of approximately 30-month-old Japanese Black steers. After confluence, differentiation was induced by 1-methyl-3-isobutyl-xanthine, dexamethasone, insulin and troglitasone for 2 days, and then subsequently cultured for 6 days. The cells were treated with activin A during the induction of differentiation (the early phase of differentiation) or throughout the differentiation period. We measured the terminal differentiation markers such as glycerol-3-phosphate dehydrogenase (GPDH) activity, lipid accumulation, and the expression of adipocyte fatty acid-binding protein mRNA at the end of cultures. Activin A suppressed the induction of all differentiation markers regardless of the duration of treatment. The treatment with activin A also reduced the expression of peroxisome proliferator-activated receptor (PPAR) gamma and CCAAT/enhancer binding protein (C/EBP) alpha mRNAs without affecting the expression of C/EBPbeta mRNA. We also observed that follistatin completely rescued the inhibitory effect of activin A on bovine preadipocyte differentiation. Furthermore, the higher doses of follistatin increased GPDH activity even in the presence of activin A compared with the cells treated with neither activin A nor follistatin. Additionally, the SV cells expressed activin A and myostatin mRNAs. These results suggest that activin A inhibits bovine preadiopocyte differentiation via affecting transcriptional cascade upstream of PPARgamma and C/EBPalpha expressions, and that follistatin suppresses the inhibitory effect of activin A on bovine preadipocyte differentiation. Endogenous activin A and/or myostatin possibly inhibit the differentiation of bovine preadipocytes.

Bone engineering of the rabbit ulna

PURPOSE

The purpose of the present preliminary study is to show that a novel 3-dimensional porous silica-calcium phosphate nanocomposite (SCPC) can provide a controlled release of rhBMP-2 and regenerate bone in a load-bearing segmental defect.

MATERIALS AND METHODS

A bone replica of the rabbit ulna was created from SCPC powder using rapid prototyping technology. The ceramic bone replica was coated with rhBMP-2 and then implanted into a 10-mm segmental defect created in a rabbit ulna and fixated with a 1-mm titanium adaptation plate. Bone healing was evaluated using computed tomography (CT) scan, histomorphometry, and biomechanical techniques. The release kinetics of rhBMP-2 and the dissolution kinetics were also determined in vitro. Statistical analysis was performed to compare the biomechanical strength of the grafted bone with the contralateral unoperated ulna.

RESULTS

After 4 weeks, CT scans showed that the critical size defect had been replaced by newly formed bone. Torsional testing of the ulna after 12 weeks showed restoration of maximum torque and angle at failure. Histological evaluation showed that the regenerated bone had the morphological characteristics of mature bone. SCPC provided a sustained release profile of an effective dose of rhBMP-2 for 14 days.

CONCLUSIONS

The SCPC-rhBMP-2 hybrid enhanced bone regeneration in a load-bearing segmental defect in a rabbit ulna. The regenerated bone acquired morphology and mechanical strength typical for natural bone. The enhanced bone formation correlates well with the surface bioactivity and effective release profile of rhBMP-2. The present preliminary study shows the proof of principles that porous, resorbable, bioactive SCPC-rhBMP-2 tissue engineering hybrid can serve as a substitute for autologous bone in load-bearing applications.

Androgens negatively regulate myostatin expression in an androgen-dependent skeletal muscle

Myostatin is an important negative regulator of skeletal muscle growth, while androgens are strong positive effectors. In order to investigate the possible interaction between myostatin and androgen pathways, we followed myostatin expression in the androgen-dependent levator ani (LA) muscle of the rat as a function of androgen status. By testosterone deprivation (castration), we induced LA growth arrest in young male rats, whilst atrophy in adult ones, however, both processes could be reversed by testosterone supplementation. After castration, a significant up-regulation of active myostatin protein (and its propeptide) was found, whereas the subsequent testosterone treatment reduced myostatin protein levels to normal values in both young and adult rats. Similarly, a testosterone-induced suppression of myostatin mRNA levels was observed in castrated adult but not in young animals. Altogether, androgens seem to have strong negative impact on myostatin expression, which might be a key factor in the weight regulation of LA muscle.

Bone morphogenetic protein-7 delays podocyte injury due to high glucose

BACKGROUND

The molecular pathogenesis of diabetic glomerulosclerosis remains unknown, but recent studies suggest that podocyte damage may play a role. Bone morphogenetic protein 7 (BMP-7) is physiologically expressed in podocytes and tubular epithelial cells. Our previous studies show that BMP-7 reverses glomerular and tubulointerstitial damage in diabetic rats, but there is little known about possible effects of BMP-7 on podocytes. We postulate that high glucose may injure the podocyte by altering structural proteins such as synaptopodin and podocin. This study investigates the effect of high glucose on mouse podocytes, expression of synaptopodin and podocin under normal and high glucose and the treatment effect of BMP-7 on these molecules. Human diabetic glomeruli are studied in parallel.

METHODS

Conditionally immortalized mouse podocytes were exposed to media containing normal (NG) or high (HG) glucose for 2 weeks. Synaptopodin, podocin and BMP-7 gene transcription and protein were assayed with real-time PCR, Western blot or immunohistochemistry, respectively. Synaptopodin and podocin mRNA and protein was evaluated using podocytes incubated in HG for 1 week, in the presence of low (10 ng/ml) and high (300 ng/ml) dose recombinant BMP-7 (rhBMP-7). Human diabetic glomeruli were excised from renal biopsies by laser capture micro-dissection (LCM) and endogenous BMP7 and synaptopodin and podocin were determined by RT-PCR and/or immunohistochemistry.

RESULTS

Culture of podocytes in HG decreases synaptopodin, podocin and BMP-7 transcription and protein synthesis compared to NG. Treatment with rhBMP-7 restores synaptopodin and podocin mRNA and protein. Decreased BMP-7 and synaptopodin is also observed in human diabetic glomeruli both at the transcription and protein level.

CONCLUSIONS

BMP-7 may confer resistance to hyperglycaemic injury via synaptopodin and podocin suggesting novel BMP7 therapies for diabetic glomerulosclerosis.