STAT1/3 and ERK1/2 synergistically regulate cardiac fibrosis induced by high glucose.

BACKGROUND: Hyperglycaemia promotes the proliferation of cardiac fibroblasts (CFs) and collagen synthesis in CFs. However, the molecular mechanism underlying the effects of HG on proliferation and collagen synthesis of CF, is not completely understood. OBJECTIVES: The objectives of the present study were to determine whether the STAT proteins has a functional role in high glucose-induced proliferation of CFs and collagen synthesis in vitro and whether the STAT signaling pathway and MAPK signaling pathway have synergetical effects on high glucose-mediated cardiac fibroblasts proliferation and collagen synthesis. METHODS: Rat CFs were cultured in Dulbecco's modified Eagle's medium, supplemented with 5.5 or 25 mmol/L D-glucose, in the presence of absence of STAT1 inhibitor Fludarabine, STAT3 inhibitor S31-201 and ERK1/2 inhibitor PD98059. Proliferation were measured by the 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, the production of Type I and III collagen was evaluated using real-time quantitative RT-PCR and ELISA, and the phosphorylation expression of STAT1 and STAT3 were analyzed by Western blot. RESULTS: High glucose treatment promoted the proliferation of cardiac fibroblasts and collagen types I and III synthesis. High glucose treatment induced STAT1 and STAT3 phosphorylation in cardiac fibroblasts, the mode and level of STAT1 and STAT3 phosphorylation were significantly different. Fludarabine and S31-201 could both inhibited high glucose stimulated proliferation of cardiac fibroblasts and collagen types I and III synthesis with different effects. Combination of Fludarabine and PD98059 or combination of S31-201 and PD98059 both exhibited stronger inhibitions on proliferation of cardiac fibroblasts and collagen types I synthesis, but the effects and functional modes are different. CONCLUSION: Both STAT1 and STAT3 mediate the proliferation of cardiac fibroblasts and collagen synthesis induced by high glucose. STAT1 and STAT3 both have synergetic effects with ERK1/2 on regulating proliferation of cardiac fibroblasts and collagen types I synthesis.

Autoimmune hypophysitis may eventually become empty sella.

Autoimmune hypophysitis (AH) is commonly believed to be a rare chronic inflammatory condition of the pituitary gland. In clinical practice, however, the disease is often seen indeed. It typically presents with hypopituitarism and pituitary mass found by MRI. We report here unusual presentations of two females with AH followed by empty sella syndrome. The two females, aged at 64 and 57-years-old, presented with anterior pituitary dysfunction, diplopia and diabetes insipidus. By MRI the two patients shared the common characteristics with diffuse homogenous contrast enhancement of the gland and increased stalk thickness. After a long period treatment with glucocorticoids, empty sella was eventually detected by MRI.

[Clinical analysis of drug-induced Pseudo-Bartter's syndrome: a report of five cases].

OBJECTIVE: To summarize the clinical characteristics and outcomes of Pseudo-Bartter's syndrome and explore its pathogenesis. METHODS: The clinical data of 5 cases of Pseudo-Bartter's syndrome at our ward from May 2008 to December 2010 was analyzed retrospectively. RESULTS: All patients were female. Long-term regimen of purgative or diuretics was prescribed. The clinical features included normotension, hypokalemic alkalosis and activation of renin-angiotensin-aldosterone. The pathological results of 3 cases of kidney biopsy showed the hyperplasia of juxtaglomerular apparatus, thickness of arteriole, infiltration of lymphocytes and monocytes and degeneration of renal tubule. Upon a definitive diagnosis, purgative or diuretics was discontinued and supplement therapy of potassium chloride initiated. The results of laboratory tests reverted to normal ranges within 4 weeks. CONCLUSION: Purgative or diuretics should be prescribed appropriately to avoid the occurrence of Pseudo-Bartter's syndrome.

[Clinical analysis of 6 cases of Bartter syndrome].

OBJECTIVE: To summarize the clinical characteristics of Bartter syndrome and investigate its pathogenesis. METHODS: The clinical data of 6 cases of Bartter syndrome at our hospital from November 2006 to May 2010 were analyzed retrospectively. RESULTS: The onset age of Bartter syndrome was 13-35 years old. The main symptoms included weakness (6/6), paralysis (1/6), numbness (5/6) and tetany (4/6). All patients had normal blood pressure. The biochemical tests showed persistent hypokalemia, metabolic alkalosis (6/6) and hyperreninemia. The pathological examination of deltoid muscle biopsy showed the swelling, degeneration and necrosis of myocytes and the deposition of immunocomplex in myolemma. And the pathological examination of renal biopsy showed the hyperplasia of juxtaglomerular apparatus (5/6) and the deposition of immunocomplex. All symptoms were relieved after a therapy of potassium supplementation or a combination of indomethacin, spironolactone and immunosuppressant. CONCLUSION: When such clinical features as weakness, paralysis, tetany, hypokalemic alkalosis and normotension are encountered, Bartter syndrome should be suspected. Serum electrolytes, blood gas analysis and activation of the renin-angiotensin-aldosterone system should be examined for a definite diagnosis. The treatment of choice includes potassium and magnesium supplementation or in combination with prostaglandin synthetase inhibitor, aldosterone antagonist and immunosuppressant. Immunologic mechanism may participate in the course of Bartter syndrome.

[The protective effects of cyclosporine A on aortic immunological injuries in STZ-induced diabetic rats].

OBJECTIVE: To investigate the autoimmune injuries of diabetic macrovascular disease (aorta) and the protective effects of immunosuppressive agent (cyclosporine A, CsA) on aortic injuries in streptozotocin (STZ)-induced diabetic rats. METHODS: STZ-induced diabetic rats were assigned randomly to 6 groups which received low (BML or AML, 1 mgxkg(-1)xd(-1)), middle (BMM or AMM, 4 mgxkg(-1)xd(-1)) or high (BMH or AMH, 8 mgxkg(-1)xd(-1)) dose of CsA from 1 week before or after STZ for 8 weeks. Diabetic rats without any treatment, insulin-treated diabetic rats and normal rats were also monitored simultaneously and served as control groups. The pathologic abnormalities of the aorta were verified by HE, Masson staining and electronmicroscopy. The depositions of immunoglobulins (IgG, IgM and IgA) were determined by immunohistochemistry and immunofluorescence methods. RESULTS: At the end of study, lymphocytes infiltration and collagen content (26 582 +/- 6901) were significantly higher in diabetic aorta than those in non-diabetic aorta (Collagen: 7482 +/- 3491, P < 0.01). The deposited IgG and IgA were also significantly increased in diabetic aorta compared with non-diabetic aorta (IgG: 11 789 +/- 2491 vs. 2518 +/- 1066, P < 0.01; IgA: 17 430 +/- 3159 vs. 1135 +/- 758, P < 0.01). These changes were not affected by insulin while CsA intervention significantly reduced aortic collagen content (BMH: 13 518 +/- 5440, P < 0.01 vs. STZ) and immunoglobulin deposition (BMH: IgG: 7584 +/- 4462; IgA: 6176 +/- 1900, all P < 0.01 vs. STZ). These immunoglobulin deposition changes were confirmed by results of immunofluorescence. Aortic collagen accumulation was positively correlated to aortic immunoglobulin deposition (IgG, r = 0.556, P < 0.01; IgA, r = 0.661, P < 0.01). CONCLUSIONS: Our data suggest that the autoimmune injuries might be a promoting factor in the pathogenesis of the diabetic macrovascular disease which could lead to the development of macrovascular disease. Immunosuppressive agent, such as CsA, could inhibit the abnormal deposition of immunoglobulins and therefore, delay the development of diabetic macrovascular disease in this model.

[The effects of cyclosporine A on immunoglobulins deposition in retina of streptozotocin-induced diabetic rats].

OBJECTIVE: To study the autoimmune injuries on diabetic retinopathy (DR) and the protective effects of immunosuppressive therapy with cyclosporine A (CsA) on the DR of streptozotocin (STZ)-induced diabetic rats. METHODS: STZ-induced diabetic rats were randomly divided into 3 groups: group 1: diabetic group without any treatment; group 2: insulin-treated group; group 3: CsA-treated group which was further divided into 2 subgroups: subgroup A: CsA was given 1 week before hyperglycemia appeared and subgroup B: CsA was given one week after hyperglycemia appeared. Subgroup A and subgroup B were further subdivided into 3 groups respectively, based on the dose of CsA (1, 4 and 8 mg x kg(-1) x d(-1)). As a control group, normal rats were also simultaneously monitored. The pathologic changes in the retina were investigated with HE stain and the deposition of immunoglobulins was detected with immunohistochemistry and immunofluorescent microscopy. RESULTS: After 8 week, the deposition of IgG, IgA and IgM was quite significant in the retina of diabetic rats. The data also suggested that insulin treatment had no effects on the DR. In contrast,with CsA intervention, the deposition of immunoglobulins on the retina of diabetic rats vanished. CONCLUSIONS: Autoimmune injuries were shown, in the present study, to play a critical role in the pathogenesis of diabetic retinopathy. Immunosuppressive treatment with CsA showed protective effects by inhibiting the deposition of immunoglobulins in the retina of diabetic rats.

[Regulation of receptor activator of nuclear factor kappaB ligand and osteoprotegerin expression by prostaglandin E2 in osteoblastic-like cells].

OBJECTIVE: To investigate the regulation of receptor activator of nuclear factor kappaB ligand (RANKL) and osteoprotegerin (OPG) mRNA expression by prostaglandin E2 (PGE2) in osteoblastic-like cells and involved signaling pathways. METHODS: Rat UMR106 osteoblast-like cells were cultured and treated with various dose of PGE2 or regulators of different signaling pathways such as protein kinase A, protein kinase C, ERK-MAPK and calcium/calmodulin pathways for different period of time,the cells were then harvested at indicated time points, total RNA were isolated and RANKL/OPG mRNA expression were studied by real-time PCR. RESULTS: PGE2, Forskolin and db-cAMP increased RANKL mRNA by 2.8 times (P = 0.002), 2.2 times (P = 0.006) and 2.1 times (P = 0.005) respectively, and inhibited OPG mRNA expression by 12% (P < 0.01), 85% (P = 0.005) and 70% (P = 0.013) respectively, while RANKL and OPG mRNA expression were down-regulated by A23187 by 58% (P = 0.002) and 53% (P = 0.017) respectively. As for inhibitory experiments, the stimulatory effects of PGE2 on RANKL mRNA expression could be inhibited only by KT-5720 by 53% (P < 0.01), while the other inhibitors did not have any effect at all. The inhibitory effects of PGE2 on OPG mRNA expression were partially blocked by KT-5720 by 47% (P = 0.01), verapamil by 38% (P = 0.029) and W7 by 43% (P < 0.01) respectively, while KN-62, chelerythrine and PD98059 had no effects. CONCLUSION: PGE2 can up-regulate the expression of RANKL but down-regulate the expression of OPG. The up-regulation of RANKL mRNA expression by PGE2 was mediated through the activation of PKA signaling pathway while PGE2 induced down-regulation of OPG mRNA expression was predominantly mediated via PKA as well as the Ca2+ /Calmodulin signaling pathways.

[Relationship between gastrointestinal dyskinesis and gastrointestinal neurons in diabetic mellitus: experiment with rats].

OBJECTIVE: To investigate the relationship between gastrointestinal dyskinesis and histologic changes of gastrointestinal myenteric plexus cholinergic and nitrergic neurons in STZ-induced diabetic rats. METHODS: 45 SD rats were randomly divided into control group, diabetic group and insulin group. 16 weeks after diabetic model established, gastrointestinal motility of rats was measured and histologic changes of myenteric plexus cholinergic neuron and nitrergic neuron was observed. RESULTS: Compared with control group, gastrointestinal motility of diabetic group was markedly slow (P < 0.01), the myenteric plexus cholinergic neuron counting of gastric antrum and small intestine were significantly decreased (6.6 +/- 2.9 vs 15.7 +/- 3.8 15.6 +/- 10.3 vs 22.6 +/- 7.4, P < 0.01), yet the number of nitrergic neuron only markedly reduced in gastric antrum (5.3 +/- 1.2 vs 11.8 +/- 2.2, P < 0.01). The gastrointestinal mobility, gastric antrum nitrergic neuron and small intestine cholinergic neuron counting of insulin group were markedly higher than that of diabetic group (P < 0.05), yet lower than that of control group (P < 0.01). CONCLUSION: The gastrointestinal dyskinesis of STZ-induced diabetic rats might be associated with lesions of gastrointestinal myenteric plexus cholinergic neuron and nitrergic neuron. Insulin intensive therapy can partly ameliorate diabetic gastrointesternal dyskinesis.

[Significance of ultrasound bone measurement in diagnosis of hyperthyroidism].

OBJECTIVE: To evaluate the role of ultrasound in bone density measurement in patients with hyperthyroidism. METHODS: The speed of sound (SOS) through distal radius and midshaft tibia of 118 patients with hyperthyroidism 138 males and 80 females, aged 20 approximately 73, were measured with ultrasonic apparatus, the bone mass density (BMD) was measured at the lumbar spine and proximal femur with dual energy X-ray absorptiometry, the serum levels of total thyroxine (TT(4)), total triiodothyronine (TT(3)), free thyroxine (FT(4)), free triiodothyronine (FT(3)), and thyroid stimulating hormone (TSH) were measured by radioimmunoassay, and alkaline phosphatase (ALP) was measured by routine method. RESULTS: The SOS of the patients with hyperthyroidism was significantly lower than that of the healthy subjects (P < 0.05). A strong positive correlation was found between SOS and BMD. The prevalence of SOS (Z < -1, Z < -2.5) through distal radius and midshaft tibia was significantly higher than that of BMD (Z < -1, Z < -2.5) at lumbar spine and proximal femur in the patients with hyperthyroidism. A negative linear correlation was found between SOS and ALP. CONCLUSION: SOS may be one of the significant markers for abnormal bone metabolism for hyperthyroidism.

[Effects of OGP(10-14) and its derivative G38I on proliferation and differentiation of rat osteoblasts in vitro].

OBJECTIVE: To investigate the effects of the carboxyl end of osteogenic growth peptide (OGP)-OGP((10-14)) and its derivative G38I on the proliferation and differentiation of osteoblasts (OBs). METHODS: Osteoblasts were isolated from the calvariae of newborn SD rats and cultured to G3. OGP((10-14)) or G38I of the concentrations of 10(-15) to 10(-7) mol/L were added to culture medium for 48 hours respectively. The number of cells was counted and MTT analysis was used to examine the proliferation of the cells. The ultrastructure of cells was investigated by electron microscopy. The osteoblasts of G3 were divided into experimental groups, treated with OGP((10-14)) or G38I of the concentration of 10(-11) mol/L for 48 hours, and control group. The alkaline phosphatase activity in the culture medium was measured. The protein expression level of type-I collagen was evaluated by immunohistochemistry. The core binding factor 1 (Cbfa1) and type-I collagen mRNA level of osteoblasts were determined by RT-PCR. RESULTS: With a biphasic effect on, OGP((10-14)) and G38I stimulated the number enhancement of OBs dose-dependently at low concentration and inhibited it at high concentration. The numbers of OB were the highest (37 x 10(4)/ml +/- 7 x 10(4)/ml and 30 x 10(4)/ml +/- 5 x 10(4)/ml respectively) when treated by OGP((10-14)) or G38I of the concentration of 10(-11)mol/L. The rough endoplasm net was flourishing and the secreting vesicle was abounding in the experimental cells. There was calcium crystal in the control cells. The activity of alkaline phosphatase in the culture medium of the OGP (10(-14)) and G38I groups were higher than that in the control group (4.47 U/g and 3.82 U/g vs 2.21 U/g). The protein expression level of type-I collagen was higher and the mRNA levels of Cbfa1 and type-I collagen were higher in the OGP((10-14)) and G38I groups were increased in the experimental groups in comparison with the control group (P < 0.05, P < 0.01, and P < 0.05). CONCLUSION: They stimulated cell number enhancement dose dependently at low concentration and followed by inhibition at high concentration. Just as the native OGP, OGP((10-14)) and its derivative G38I stimulate the proliferation of osteoblasts, and improve their activity, up-regulate the Cbfa1 and type-I collagen mRNA expression levels and increase the collagen synthesis, thus promoting the differentiation and osteogenic effect of osteoblasts.

[Impacts of osteoclast-like cells cultured on bone wafer and their sub-cellular structures on osteoblast].

OBJECTIVE: To investigate the effects of osteoclast-like cells (OLC) and its sub-cellular structures on the osteoblast (OB) differentiation and function. METHODS: Spleen cells from C57 mice administrated with 5-fluorouracil were induced by IL-3, 6 and granulocyte-macrophage colony stimulating factor (GM-CSF), and 1alpha, 25-(OH)(2)D(3) to obtain massive OLCs. These OLC cells were cultured in culture fluid and on bone wafers (called bolcs). Osteoblasts were cultured and added with NaF, OLCs of two kinds, culture fluid free of OLC, and sub-unit structures such as nucleus, mitochondria, and cytoplasma from OLCs for 5 days. The proliferation rate of OBs was measured by MTT method and the alkaline phophatase (ALP) activity was measured by PNPP method. Immunochemistry was used to detect the core-binding factor alpha1 (Cbfalpha1) in the OBs, Enzyme linked immunosorbent assay was used to measure the osteocalcin. RESULTS: The OB number was lower in the OLC (1.288 +/- 0.039), OLC cytoplasm (1.138 +/- 0.024), 50% OLC culture fluid (1.203 +/- 0.033), 50% OLC culture medium of OLCs cultured on bone wafer (1.128 +/- 0.028) in comparison with the pure OB group (1.393 +/- 0.016, all P < 0.05). The increase functions of OBs by OLC cultured on bone wafer and their nucleus and mitochondria were all more significant than those of the OLCs not cultured on bone wafer. The ALP activity was increased in the NaF (1.027 +/- 0.024), OCL cytoplasm (1.850 +/- 0.033), 50% OLC medium (2.074 +/- 0.065), 50% OLC medium of OLCs cultured on bone wafer (1.718 +/- 0.048), and mitochondria and cytoplasm of the OLC cultured on bone wafer groups (1.246 +/- 0.037, all P < 0.05). NaF (0.0825 +/- 0.0025), OLCs (0.0775 +/- 0.0025), nucleus (0.0775 +/- 0.0025), mitochondria (0.0875 +/- 0.0025), and cytoplasm of OLCs (0.1100 +/- 0.0007), 50% OLC medium (0.0900 +/- 0.0000), 50% OLC medium of OLCs cultured on bone wafer (0.1200 +/- 0.0041), OLCs cultured on bone wafer and nucleus, mitochondria, and cytoplasm of OLCs cultured on bone wafer all significantly increase the oeteocalcin activity of OBs (0.525 +/- 0.0063, all P < 0.05). NaF (57.6% +/- 2.6%), OLC cytoplasm (45.3% +/- 4.7%), 50% OLC medium (46.6% +/- 3.3%), 50% medium of OLCs cultured on bone wafer (54.0% +/- 2.1%), OLCs cultured on bone wafer (44.8% +/- 3.0%), and cytoplasm of OLCs cultured on bone wafer (48.7% +/- 3.5%) all significantly increased the Cbfalpha1 protein in the OBs (32.8% +/- 4.5%, all P < 0.05). CONCLUSION: The sub-cellular elements of OLC and the supernatant of OLC culture media free of OLC promote the functions of OB, especially the OLCs cultured on bone wafer.

Effects of Cordyceps sinensis on the Expressions of NF-κB and TGF-ß1 in Myocardium of Diabetic Rats.

Objective. To investigate the effect of Cordyceps sinensis (CS) on the expressions of NF-κB and TGF-ß1 in myocardium of streptozotocin-induced diabetic rats. Methods. A total of 53 healthy male SD rats, mice age of 8 weeks and weight of 220 ± 20 g, were randomly divided into five groups by randomized block design: normal control group (n = 10), diabetic group (n = 10), low dose of CS group (n = 12; CS 0.6 g·kg(-1)·d(-1)), middle dose of CS group (n = 11; CS 2.5 g·kg(-1)·d(-1)), and high dose of CS group (n = 10; CS 5 g·kg(-1)·d(-1)). The diabetic models with tail intravenous injection by streptozotocin (45 mg·kg(-1)). Diabetic rats were sacrificed after 8 weeks; the expressions of NF-κB and TGF-ß1 proteins and mRNA in the cardiac muscle were determined by using immunohistochemistry staining and reverse transcription polymerase chain reaction (RT-PCR) method. The data were analyzed using one factor analysis of variance. Result. The expressions of NF-κB and TGF-ß1 proteins and mRNA in the cardiac muscle of diabetic rats were significantly raised (P < 0.05), which could be decreased by CS (P < 0.05). Conclusions. The changes on the expressions of NF-κB and TGF-ß1 in myocardium may be involved in the occurrence of diabetic cardiomyopathy (DC). CS may play its role on myocardial protection by regulating the expressions of NF-κB and TGF-ß1 in myocardium.

Efficacy and safety of avandamet or uptitrated metformin treatment in patients with type 2 diabetes inadequately controlled with metformin alone: a multicenter, randomized, controlled trial.

BACKGROUND: At present, China has listed the compound tablet containing a fixed dose of rosiglitazone and metformin, Avandamet, which may improve patient compliance. The aim of this study was to evaluate the efficacy and safety of Avandamet or uptitrated metformin treatment in patients with type 2 diabetes inadequately controlled with metformin alone. METHODS: This study was a 48-week, multicenter, randomized, open-labeled, active-controlled trial. Patients with inadequate glycaemic control (glycated hemoglobin [HbA1c] 7.5-9.5%) receiving a stable dose of metformin (≥1500 mg) were recruited from 21 centers in China (from 19 November, 2009 to 15 March, 2011). The primary objective was to compare the proportion of patients who reached the target of HbA1c ≤7% between Avandamet and metformin treatment. RESULTS: At week 48, 83.33% of patients reached the target of HbA1c ≤7% in Avandamet treatment and 70.00% in uptitrated metformin treatment, with significantly difference between groups. The target of HbA1c ≤6.5% was reached in 66.03% of patients in Avandamet treatment and 46.88% in uptitrated metformin treatment. The target of fasting plasma glucose (FPG) ≤6.1 mmol/L was reached in 26.97% of patients in Avandamet treatment and 19.33% in uptitrated metformin treatment. The target of FPG ≤7.0 mmol/L was reached in 63.16% of patients in Avandamet treatment and 43.33% in uptitrated metformin treatment. Fasting insulin decreased 3.24 ± 0.98 µU/ml from baseline in Avandamet treatment and 0.72 ± 1.10 µU/ml in uptitrated metformin treatment. Overall adverse event (AE) rates and serious AE rates were similar between groups. Hypoglycaemia occurred rarely in both groups. CONCLUSIONS: Compared with uptitrated metformin, Avandamet treatment provided significant improvements in key parameters of glycemic control and was generally well tolerated. REGISTRATION NUMBER: ChiCTR-TRC-13003776.

Expression, purification and bioactivity characterization of extracellular domain of murine osteoprotegerin ligand.

Osteoprotegerin ligand (OPGL) is a key regulator of formation and activation of osteoclasts. In the present study, the cDNA encoding the extracellular domain of murine OPGL (sOPGL) was synthesized by RT-PCR and cloned into fusion expression vector pET-42a(+) in a certain strategy on purpose that the fusion tag could be completely removed by factor Xa from the expressed fusion protein without any vector-encoded sequence left. Induced with IPTG, the recombinant E. Coli cells produced a 47 kD protein in high level that could be recognized, through Western blotting analysis, by the antibody against OPGL. The expressed products were purified through Glutathione-sepharose 4B affinity chromatography. Along with the fusion molecule, a protein about 30 kD was also specifically bound to the resin. The 30 kD molecule could be recognized by polyclonal antibody against GST-IGF-1, but not by antibody against OPGL. It suggested that the 30 kD molecule was derived from the degradation of the fusion protein. After the cleavage with factor Xa and further purification, the fusion tag was removed and the recombinant sOPGL was obtained. Finally, we confirmed that the recombinant sOPGL could promote osteoclast formation from mouse bone marrow cells in a dose dependent manner.

[Losartan downregulates the expression of transforming growth factor beta type I and type II receptors in kidney of diabetic rat].

OBJECTIVE: To investigate the influence of losartan on the expression of transforming growth factor-beta type I and type II receptors (TGF beta RI, TGF beta RII) in kidney of diabetic rat model. METHODS: The Wistar rats were randomly divided into 3 groups with 10 rats in each group: normal control group (group C), diabetic rat model group (group DM, the model was reproduced by intravenous injection of 50 mg/kg streptozotocin), and the group of diabetic rat model treated with losartan (group DL, 10 mg.kg(-1).d(-1) of losartan intragastrically since the 2nd day of streptozotocin injection). Eight weeks later, the mRNA and protein expressions of TGF beta RI, TGF beta RII and fibronectin in renal cortices of all 3 groups were measured by semiquantitative reverse transcription-polymerase chain reaction and by histoimmunochemical methods. The blood glucose, urea and creatinine were detected by biochemical assay and the blood insulin and angiotensin II by radioimmunoassay. The urine albumin excretion ratio was examined by sulfosalicylic acid assay. RESULTS: The mean glomerular volume, kidney weight/body weight ratio, urine albumin excretion ratio, blood urea and creatinine were significantly elevated in group DM than that in group C (P < 0.05). The mRNA and protein expressions of TGF beta RI, TGF beta RII and fibronectin in renal cortices of group DM were significantly increased than that in group C as well (P < 0.05). The increase in mean glomerular volume, kidney weight/body weight ratio, urine albumin excretion ratio, blood urea and creatinine in group DL was significantly attenuated as compared to group DM. The mRNA and protein expressions of TGF beta RI, TGF beta RII and fibronectin in renal cortices of group DL were also significantly reduced as compared to that in group DM (P < 0.05). CONCLUSION: Losartan may have protective effects on the kidney of diabetic rat model. The mechanism of the protection might related to its downregulatory effect on the expression of TGF beta system, which inhibited the hypertrophy of kidney cells and reduced the synthesis of extracellular matrix.

[Bone histomorphometry study on lumbar vertebrae microstructure of ovariectomized goats].

OBJECTIVE: To demonstrate the histomorphometric changes of postmenopausal osteoporosis (PMO) goat model after bilateral ovariectomy (OVX). METHODS: Fifteen female goats were randomly enrolled into four groups: 3 goats without any treatment (group C), 3 goats sham-operated only (group S), 4 goats 6 months after OVX (group OVX6M), 5 goats 18 months after OVX (group OVX18M). On the 21st and 9th day prior to sacrifice, tetracycline was given to them in order to label the bone for dynamic study. The first lumbar vertebrae from each goat were reserved for bone histomorphometric study. RESULTS: As compared with group C and S, the trabecular bone volume (TBV)/total tissue volume, TBV/sponge bone volume, mean trabecular plate thickness (MTPT) and mean trabecular plate density in OVX6M and OVX18M groups were significantly lower (P < 0.01, but MTPT: P < 0.05), while the mean trabecular plate space, surface/volume ratio of the trabecular bone, single labelled surfaces [Sfaces(s)], double labelled surfaces [Sfaces(d)], Sfaces (d + 1/2s), mean osteoid seam width, mineralization lag time, speed of bone formation in the tissue levela and osteoid maturation period were significantly higher (P < 0.01). CONCLUSION: In OVX goats, bone loss accelerated, resulting in destroyed bone microstructure, fasten frequency of activation and high bone turnover. Therefore, the bone resorption process exceeds over the bone formation, successfully establishing a high turnover osteoporotic metabolic model.

[Expression of Fas, FasL, and NF-kappa B in the process of osteoclast-like cell apoptosis effected by sodium fluoride].

OBJECTIVE: To detect the changes in the expression of apoptosis signals: Fas, FasL and NF-kappa B in the process of osteoclast-like cell (OLC) apoptosis effected by sodium fluoride. METHODS: After co-culture of osteoclast-like cells with 0, 5, 10 and 15 mg/L sodium fluoride, Fas, FasL and NF-kappa B antibody expressions were detected by immune-histochemistry. RESULTS: The expression of Fas and FasL increased with the concentration of the sodium fluoride, however the expression of NF-kappa B decreased with the concentration of sodium fluoride. CONCLUSION: In the process of OLC apoptosis induced by sodium fluoride, the expression of Fas and FasL increased, and that of NF-kappa B decreased with the concentration of sodium fluoride respectively, and the changes of the expression present a dose-dependent pattern.

[Effect of nylestriol on bone remodeling in ovariectomized rats].

OBJECTIVE: To clarify the effects of nylestriol on microarchitecture and interleukin-6 (IL-6) mRNA expression in tibial bone in ovariectomized rats. METHODS: 30 female rats were randomly allocated into 3 groups: sham, OVX and nylestriol-treated group. Nylestriol-treated group were ovariectomized, then fed with nylestriol for 3 months and the bone mineral density (BMD) was measured in lumbar vertebra by dual energy x-ray absorptiometry. After sacrifice of the animal, bone histomorphometric parameters were measured to study the changes in bone microarchitecture, and RT-PCR was performed to detect the expression of IL-6 mRNA in bone tissue. RESULTS: BMD was significantly reduced, while IL-6 mRNA level elevated in the OVX group compared with the sham group. Static histomorphometric data showed that the trabecular bone volume, mean trabecular plate thickness and density were reduced while the mean trabecular plate space elevated remarkably in the OVX group in comparison with that in the sham group. As for dynamic parameters, trabecular osteoid surface, tetracyclin labeled surface and bone turnover rate were increased while osteoid maturation rate decreased significantly in the OVX group compared with the sham group. BMD, IL-6 mRNA expression and bone histomorphometric parameters were improved in nylestriol-treated rats. CONCLUSION: Nylestriol plays an important role in maintaining bone volume and improving bone microarchitecture by markedly inhibiting bone turnover and bone resorption, which might be to some degree attributed to reduced IL-6 expression.

[Distribution of tetracycline-arginine-glycine-aspartate-tyrosine in mice and its effect on bone].

OBJECTIVE: To investigate the distribution of tetracycline-arginine-glycine-aspartate-tyrosine (T-RGDY) in mice and its effect on bone. METHODS: 125-labeled T-RGDY was studied for its distribution in mice and for its effects on bone by histomorphometry in ovariectomized rats. RESULTS: The 125I-labeled T-RGDY was more concentrated in the osteoporotic bone than in the normal bone. Compared with ovariectomy group, the morphologic index such as trabecular bone volume/total tissue volume (TBV/TTV), TBV/sponge bone volume (SBV), and mean trabecular plate thickness (MTPT) in T-RGDY group significantly increased (P < 0.05). As compared with sham operation group, MTPT significantly increased in T-RGDY group (P < 0.05), while TBV/SBV and mean trabecular plate density significantly decreased (P < 0.05), and TBV/TYV and mean trabecular plate spacing were almost the same as those in sham operation group (P > 0.05). CONCLUSION: T-RGDY may concentrate in bone tissue to a certain degree, which is closely related with the status of bone remodeling. T-RGDY may inhibit the bone loss caused by ovariectomy.

[Effects of supplementation of different kinds of iodine on the antioxidative ability of retina in iodine deficient rats].

OBJECTIVE: To study the effects of iodine supplementation (in different kinds and doses) on the antioxidative ability of retina in iodine deficient rats. METHODS: One hundred and twenty eight iodine deficient Wistar rats were randomly divided into four groups, normal dose of iodate, normal dose of iodide, high dose of iodate and high dose of iodide. Concentration of serum thyroid hormones, including total TT(3) and total TT(4), were estimated by radioimmunoassay. GSH-Px, SOD, TAOC activities and MDA content in the retina were determined using biochemical methods in the 22nd week of iodine supplementation. RESULTS: Statistical analysis showed that a significant difference in TT(3) level of serum was observed between animals treated with different doses. Serum TT(3) level in the groups treated with high doses was significantly higher than those with normal doses. However, no statistical difference could be detected at TT(4) level between animals treated with different doses. Different kind of iodine did not affect the level of thyroid hormones. Statistical analysis showed that a difference in SOD activity of retina was observed between animals treated with different doses. SOD activity in the groups with normal doses was significantly higher than that in groups with larger doses. Retina TAOC activity was significantly higher in groups treated with iodide than that in groups of iodate. Although there was no statistical difference in GSH-Px activity between different groups, it showed the same tendency as the SOD and TAOC activities, i.e. GSH-Px activity in the groups of normal doses was higher than that in the groups of high doses. GSH-Px activity in groups of iodide was higher than that in the groups of iodate. There was no significant difference in MDA content among these four groups. CONCLUSIONS: Different iodine and doses have certain effects on the antioxidative ability of retina in iodine deficient rat. The rats supplemented potassium iodide at normal dose showed higher antioxidative ability of the retina than those of the others.