Involvement of AP-1 in p38MAPK signaling pathway in osteoblast apoptosis induced by high glucose.

We investigated the effect of p38MAPK/AP-1 (activator protein-1) signaling on the apoptosis of osteoblasts induced by high glucose. A lentivirus vector of small hairpin RNA (shRNA) targeting p38MAPK was constructed in vitro. Osteoblasts MC3T3-E1 cultured in vitro were treated with vehicle, high glucose, p38MAPK-shRNA transfection, p38MAPK inhibitor, and unrelated shRNA transfection. Apoptosis, protein levels of p38MAPK, and activities of AP-1 in MC3T3-E1 osteoblasts were measured using TUNEL and flow cytometry, Western blot analysis, and an electrophoretic mobility shift assay. Compared with the vehicle group, high glucose induced apoptosis of MC3T3-E1 osteoblasts and activated p38MAPK and AP-1. p38MAPK-shRNA transfection blocked the effect of high glucose stimulation, and the p38MAPK inhibitor showed similar effects as those observed in p38MAPK transfection. Unrelated shRNA had no effect on these changes in MC3T3-E1 osteoblasts induced by high glucose. Therefore, our results suggest that p38MAPK-shRNA reduce apoptosis of MC3T3-E1 osteoblasts induced by high glucose by inhibiting the p38MAPK-AP-1 signaling pathway.

Associations of depression with impaired glucose regulation, newly diagnosed diabetes and previously diagnosed diabetes in Chinese adults.

AIM: To examine the association between depression and impaired glucose regulation, newly diagnosed diabetes and previously diagnosed diabetes in middle-aged and elderly Chinese people, and whether depression was associated with different treatment regimens or durations of diabetes. METHODS: A cross-sectional study was performed among 229,047 adults living in the community aged ≥ 40 years from 25 centres in China. The self-reported depression rating scale Patient Health Questionnaire 9 (PHQ-9) was used to diagnose probable and sub-threshold depression. Glucose metabolism status was determined according to World Health Organization 1999 diagnostic criteria. RESULTS: The numbers of participants with normal glucose regulation, impaired glucose regulation, newly diagnosed diabetes and previously diagnosed diabetes were 120,458, 59,512, 24,826 and 24,251, respectively. The prevalence of sub-threshold depression in the total sample of participants was 4.8% (4.8%, 4.8%, 4.4% and 5.6% from normal glucose regulation to previously diagnosed diabetes, respectively), and the prevalence of probable depression was 1.1% (1.1%, 1.0%, 0.9% and 1.8% from normal glucose regulation to previously diagnosed diabetes, respectively). Compared with participants with normal glucose regulation, those with previously diagnosed diabetes had increased odds of probable depression [odds ratio (OR) = 1.61, 95% confidence interval (CI) 1.39-1.87] and sub-threshold depression (OR = 1.14, 95% CI 1.06-1.24), after adjustment for multiple confounding factors. Newly diagnosed diabetes or impaired glucose regulation was not associated with depression. Among those with previously diagnosed diabetes, insulin treatment was associated with greater odds of depression compared with no treatment or oral anti-diabetic medicine. CONCLUSION: Previously diagnosed diabetes, but not newly diagnosed diabetes or impaired glucose regulation, was associated with a higher prevalence of depression. Patients receiving insulin were more likely to have depression than those not receiving treatment or being treated with oral anti-diabetic medicine.

Lipoapoptosis pathways in pancreatic ß-cells and the anti-apoptosis mechanisms of adiponectin.

Lipoapoptosis is the main form of pancreatic ß-cell death in diabetes. Adiponectin is an adipocyte-derived hormone, which has anti-apoptosis effect in numerous cells. The present study was designed to explore the role of the 'extrinsic' (death receptor-induced) and the 'intrinsic' (mitochondrial) pathways in pancreatic ß-cell lipoapoptosis and the anti-apoptosis effect of adiponectin on pancreatic ß-cells. Palmitate (0.4 mmol/l) or oleate (0.4 mmol/l) was used to induce the apoptosis of Min 6 cells for 24 h. Z-LETD-FMK or Z-IEHD-FMK (40 µM) was used to inhibit the activity of caspase-8 or -9. When adiponectin was used, Min 6 cultures were pretreated in the absence or presence of fAd (5 µg/ml) for 2 h and then subjected to palmitate for 24 h. Apoptosis was evaluated using Annexin V-Cy3 kit. The expression levels of cleaved caspase-3, -8, -9, B-cell lymphoma 2 (BCL-2), and Bax were examined by Western blotting. Palmitate-induced pancreatic ß-cell apoptosis was accompanied by the activation of caspase-8, -9, and -3. Blockade of caspase-9 rather than caspase-8, showed an inhibitory effect on caspase-3 activation. Moreover, adiponectin treatment prevented palmitate-induced apoptosis by inhibition of caspase-9 activation, but not of caspase-8, and induced an upregulation of BCL-2 and a downregulation of Bax in protein level. Both extrinsic and intrinsic pathways are activated in pancreatic ß-cell lipoapoptosis, and the intrinsic apoptosis pathway is the major one. Adiponectin prevents pancreatic ß-cells from apoptosis by inhibition of intrinsic apoptosis pathway via regulation of the BCL2 family. Therefore, protection of intrinsic apoptosis pathway is a potential therapeutic strategy for diabetes.

Suppression of mesangial cell proliferation and extracellular matrix production in streptozotocin-induced diabetic mice by adiponectin in vitro and in vivo.

Renal growth, particularly hypertrophy, is a feature of diabetic nephropathy (DN). Adiponectin, an adipocyte-derived hormone, is an important regulator of cell proliferation. Recent studies have suggested that adiponectin has a protective effect in the kidney. The purpose of this study was to investigate the therapeutic effects and the underlying mechanisms of adiponectin in early DN. Mouse mesangial cells (MMCs) were cultured in media containing different concentrations of platelet-derived growth factor-BB (PDGF-BB) with or without adiponectin. MMC proliferation and expression of type IV collagen, laminin, and fibronectin were investigated. Streptozotocin-induced diabetic mice were injected intravenously with recombinant lentivirus encoding the mouse adiponectin gene (Lenti-Acdc-IRES-EGFP). Urinary microalbumin, serum adiponectin level, and expression of proliferating cell nuclear antigen, type IV collagen, laminin, and fibronectin were determined. Adiponectin inhibited the increases in MMC proliferation and expression of type IV collagen, laminin, and fibronectin induced by PDGF-BB. Adiponectin also effectively reduced renal cell proliferation and expression of type IV collagen, laminin, and fibronectin when it was introduced in vivo by lentivirus-mediated gene transfer. These findings suggest that adiponectin exerts renoprotective effects by inhibiting renal cell proliferation and reducing synthesis of extracellular matrix proteins, thus suppressing the development and progression of DN.

Adiponectin-induced inhibition of intrinsic and extrinsic apoptotic pathways protects pancreatic ß-cells against apoptosis.

Apoptosis is the main form of ß-cell death in type 2 diabetes mellitus. There are 2 major pathways leading to apoptosis, 'intrinsic and extrinsic pathways'. Adiponectin is an adipocyte-derived hormone, which plays an important role in glucose and lipid metabolism. The main aims of this study were to investigate related apoptotic pathways in diabetes and the anti-apoptosis effects of adiponectin on pancreatic ß-cell and the underlying mechanisms. Diabetic mice were generated by intraperitoneal injection of streptozotocin (STZ, 50 mg/kg/d for 5 days) and high-fat diet. Adiponectin overexpressing mice were developed by injecting lentivirus expressing mouse full length adiponectin (plenti-acdc-EGFP) through tail vein. Fourteen days after plenti-acdc-EGFP lentivirus injection, plasma adiponectin protein levels were increased 2-fold. Plasma triglyceride and glucose levels, but not total cholesterol, were significantly reduced in plenti-acdc-EGFP-treated mice. Pancreatic ß-cell apoptotic numbers and the expression of caspase-8, -9, -3 in islet increased in diabetic mice, which was reversed by elevated adiponectin in plenti-acdc-EGFP-treated mice. These results suggest that both intrinsic and extrinsic apoptotic pathways have an important role in diabetic ß-cell apoptosis. Adiponectin has antidiabetic and anti-apoptotic effects by regulating glucose and lipid metabolisms and inhibiting intrinsic and extrinsic apoptotic pathway in pancreatic ß-cells.

Adiponectin inhibits PDGF-induced mesangial cell proliferation: regulation of mammalian target of rapamycin-mediated survival pathway by adenosine 5-monophosphate-activated protein kinase.

An aberrant proliferation of mesangial cells (MCs) is one of the more important features of diabetic nephropathy (DN). Adiponectin, an adipocyte-derived hormone, has been associated with type 2 diabetes, a known cause of DN. Recent studies have suggested that adiponectin has a protective effect on the kidney. To elucidate the potential protective mechanism of adiponectin on kidney, we investigated the effects of adiponectin on platelet-derived growth factor (PDGF)-induced cell proliferation and intracellular signaling pathways in cultured Human MCs (HMCs). PDGF-induced HMC proliferation was significantly inhibited by the co-treatment of adiponectin. Adiponectin alone had no effect on HMC proliferation. The mammalian target of rapamycin (mTOR) and 40 S ribosomal S6 kinase 1 (S6K1) were activated by PDGF stimulation in HMCs. PDGF-induced mTOR and S6K1 phosphorylations were significantly attenuated by the co-treatment of adiponectin in HMC. Adiponectin alone had no effects on PDGF-receptor autophosphorylation by PDGF. We also confirmed that the inhibitory effect of adiponectin on PDGF-induced HMC proliferation was significantly suppressed by compound C, an adenosine 5'-monophosphate-activated protein kinase (AMPK) inhibitor. From these findings, it is implied that adiponectin could attenuate renal dysfunction associated with MC disorders through AMPK-mTOR signal pathway.

Association of the ADIPOQ rs17360539 and rs266729 polymorphisms with type 2 diabetes: a meta-analysis.

Published data on the association between ADIPOQ polymorphisms and type 2 diabetes are inconsistent. The present meta-analysis was performed to clarify the role of polymorphisms in proximal promoter region of ADIPOQ (rs17360539 and rs266729) in type 2 diabetes. The MEDLINE, EMBASE and Science Citation Index Expanded database were searched for eligible studies. Odd ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association. The pooled ORs were performed for per-allele model (A/a) and others genetic models. A total of 10267 T2DM patients and 12837 controls was included in the meta-analysis. Overall the -11377G allele had an 8% elevated risk of T2DM compared to -11377C allele in all subjects (P=0.034, OR=1.08, 95% CI 1.01-1.15). The -11391A allele showed no significant effect on T2DM risk in all subjects (P=0.240, OR=1.10, 95% CI 0.94-1.29) compared to -11391G allele. In the subgroup analyses by ethnicity, -11391A allele increased T2DM risk in European population (P=0.046, OR=1.09, 95% CI 1.00-1.09). In conclusion, the accumulated evidence suggested that the ADIPOQ -11377G allele is a low-penetrant risk factor for developing type 2 diabetes, but -11391A is a risk factor only in European Caucasians.

Severity of depression risk predicts health outcomes and recovery following surgery for hip-fractured elders.

UNLABELLED: This study examined how depression risk interfaces with health outcomes of hip-fractured patients during the first year after hospital discharge. Physical function recovery and health outcome trajectories were much poorer for hip-fractured elders with persistent depression risk than for those with transitory and no risk for depression. INTRODUCTION: This study examined how depression risk interfaces with the trajectories of physical activities and health-related quality of life (HRQoL) among hip-fractured elderly patients during the first 12 months after hospital discharge. METHODS: Based on 12-month scores for the Chinese version of Geriatric Depression Scale, patients over age 60 years (N = 147) were classified as (a) at persistent risk for depression, (b) at transitory risk for depression, and (c) at no risk for depression. Outcomes were measured by the Chinese Barthel Index and Medical Outcomes Study Short Form, Taiwan version, and analyzed by the generalized estimating equations approach. RESULTS: Patients who were at persistent risk for depression (n = 46, 31.3%) had much less chance of recovering activities of daily living (OR = 0.16, CI = 0.06-0.42) and walking ability (OR = 0.09, CI = 0.04-0.21) than patients at no risk for depression (n = 36, 24.5%). The trajectories of SF-36 scores for the physical and mental health summary scales were significantly different among the three depression groups; those "at persistent risk for depression" were the poorest and those "at no risk for depression" were the best. CONCLUSION: These results may provide a reference for developing timely assessments and interventions for hip-fractured elders at risk of depression.

Co-transfection of GK and mhPINS genes into HepG2 cells confers glucose-stimulated insulin secretion.

BACKGROUND: The purpose of this study was to construct an 'artificial beta cell' that can exhibit physiologic glucose-stimulated insulin secretion for the treatment of type 1 diabetes. METHODS: Retroviral vector containing the glucokinase (GK) gene and mutated human proinsulin (mhPINS) gene was constructed. HepG2 cells were first infected with recombinant retrovirus carrying the GK and mhPINS genes, then selectively cultured with G418 to obtain the positive clones. GK and mhPINS gene transcription and expression were identified by radioimmunity, Western blot and RT-PCR techniques. Finally, the dose-response effect of glucose on insulin secretion from those HepG2 cells that expressed both GK and mhPINS genes was tested with HepG2 cells that only expressed the mhPINS gene as a control. RESULTS: HepG2 cells with transferred GK and mhPINS genes were selectively cultured with G418 and the positive clones were obtained in 3 weeks. Four clones with GK and mhPINS gene expression were selected from 20 positive clones by radioimmunity and Western blot. We picked up one clone with a strong GK and mhPINS gene expression and named it clone Beta. In clone Beta, differences in insulin secretion at 0.5 and 0.75 mmol/L glucose concentrations were not significant (P>0.05) and differences in insulin secretion at 2.0, 3.0, 4.0, 5.0 and 6.0 mmol/L glucose concentrations were not significant (P>0.05), while there were significant differences in insulin secretion at other glucose concentrations(P<0.05). The artificial beta cell, clone Beta, obtained a glucose-stimulated insulin secretion with maximal insulin secretion at 1.75-2.00 mmol/L glucose concentrations. DISCUSSION: An artificial beta cell that exhibits glucose-stimulated insulin secretion can be constructed successfully.

Information processing in schizophrenia and bipolar disorder: a discriminant analysis.

Schizophrenia and bipolar disorder are two distinct categories of mental disorders in the DSM-IV. However, it is often difficult to make a differential diagnosis because of the overlapping symptoms. A potential adjunct in the classification of schizophrenia and bipolar disorder is the application of information processing models, as patients with schizophrenia and possibly those with bipolar disorder have information processing deficits. A study was conducted in which a computerized battery of information processing tasks (called COGLAB) was administered to three participant groups: patients with schizophrenia, patients with bipolar disorder, and normal controls. The tasks included the Mueller-Lyer illusion, reaction time, size estimation, a variant of the Wisconsin Card Sorting Test, backward masking, and Asarnow continuous performance. Discriminant analyses were used to investigate the differences among the three groups. Results indicated that COGLAB correctly classified 75.5% of the cases of schizophrenia and bipolar disorder. The Mueller-Lyer illusion and the number of perseverative errors on the card sort most powerfully discriminated the two groups.

The increasing use of anticonvulsants in prophylactic treatment of bipolar disorder.

The medical records of patents with bipolar disorders who received prophylactic drug treatments during three time periods from January 1983 to December 1984, January 1988 to December 1989, and from January 1993 to December 1994, were reviewed retrospectively. The percentage of lithium monotherapy sharply decreased from 96% (51/53) in the first study period to 51.9% (83/160) in the third study period. Carbamazepine monotherapy and combination of lithium and carbamazepine increased from 3.8% in the first study period to 45.6% in the third study period. These results suggest that anticonvulsants may become one of the major drug treatment strategies for bipolar disorder in the future.

Dextromethorphan phenotyping and haloperidol disposition in schizophrenic patients.

This study examined the relationship between the metabolic ratios of dextromethorphan/dextrorphan, haloperidol disposition, and the incidence of extrapyramidal side effects in schizophrenic patients. Eighteen schizophrenic patients were phenotyped with a test dose of dextromethorphan prior to the initiation of haloperidol treatment. The metabolic ratio of dextromethorphan/dextrorphan was determined in each patient. Patients were treated with oral haloperidol 10 mg/day for 2 weeks. Blood samples for haloperidol and reduced haloperidol were obtained at week 2 of haloperidol treatment. Haloperidol and reduced haloperidol plasma concentrations were assayed by HPLC with electrochemical detection. Significant correlations of dextromethorphan/dextrorphan metabolic ratios vs. plasma haloperidol concentrations, reduced haloperidol concentrations, and reduced haloperidol/haloperidol ratios were found (r = 0.726, P = 0.0007; r = 0.782, P = 0.0001; and r = 0.619, P = 0.006, respectively). Ten patients who experienced extrapyramidal side effects had higher reduced haloperidol concentrations and reduced haloperidol/haloperidol ratios than the other patients (2.49 +/- 1.42 [S.D.] ng/ml vs. 1.10 +/- 0.46 ng/ml, P = 0.014 and 0.287 +/- 0.102 vs. 0.192 +/- 0.065, P = 0.030). The former also had a trend to have higher haloperidol concentrations and dextromethorphan/dextrorphan ratios than the latter (8.04 +/- 2.91 ng/ml vs. 5.83 +/- 1.79 ng/ml, P = 0.066 and 0.023 +/- 0.017 vs. 0.011 +/- 0.010, P = 0.077). Phenotyping patients has the potential to assist clinicians in predicting plasma drug concentrations during the subsequent neuroleptic drug treatment. Further research with phenotyping and psychotropic drug metabolism in psychiatric patients is needed.

Influence of carbamazepine on Li+ ratio in healthy volunteers: an in vitro method.

Thirty-six healthy volunteers, 19 men and 17 women, were selected to study the possible influence of carbamazepine on Li+ ratio in vitro. The study used within-Ss design. The procedure for preparing and calculating Li+ ratio in vitro followed Pandey's method. Twenty milliliters of blood was withdrawn from each subject, and divided evenly into three test tubes containing sodium heparin. Test tube 1 (control) went through the regular Pandey's method; test tube 2 went through the same procedure, except both the loading and incubation media contained 35 mu mol/L of carbamazepine. The result showed that carbamazepine did not significantly alter Li+ ratio in vitro. The neurotoxicity resulting from lithium-carbamazepine combination might be related to carbamazepine alone or preexisting physical conditions or interactions not related to Li+ ratio.

[Influence of haloperidol on plasma Li+ and Li+ index].

Since Cohen and Cohen reported four cases suffering from irreversible brain damage after combined use of haloperidol and lithium, the possible toxic interaction between these two drugs has been intensively studied. The results are controversial. In this study, we used the within-Ss design to study the influence of haloperidol on the plasma Li+ level and Li+ index in 29 manic patients. Also, we used the in vitro method to study the influence of haloperidol on the Li+ index in 36 healthy volunteers. Haloperidol significantly increased the plasma Li+ levels (paired t test, t = 2.797, d.f. = 27, p < 0.01) in the in vivo study, but did not alter the Li+ index in either the in vivo or the in vitro study.

Maintenance lithium levels could be lowered: based on Taiwanese and Danish studies.

Twenty-two patients, 8 males and 14 females, who had been lithium-free for at least 1 week were included in this study. All patients took 900 mg of Lithonate at 8:00 a.m. while in a fasting state. A 5 ml blood sample was taken at 9:00 a.m., 10 a.m., 12 noon, 3 p.m., 5 p.m., 11 p.m., and at 9 a.m. and 3 p.m. on the next day. Plasma was separated immediately, and the lithium level was measured by atomic absorption spectrophotometry. The pharmacokinetic parameters were as follows: K12 (microconstant) = 0.3455 +/- 0.5345 (mean +/- SD) h-1; K21 (microconstant) = 0.1691 +/- 0.1242 h-1; K10 (microconstant) = 0.1320 +/- 0.1112 h-1; Vl (volume of distribution of central compartment) = 16.9057 +/- 5.9384 1; Vss (volume of distribution at steady state) = 38.8917 +/- 11.4540 1; V-beta (volume of distribution of elimination phase) = 46.3809 +/- 13.8742 1; alpha (distribution rate constant) = 0.5932 +/- 0.7090; and beta (excretion rate constant) = 0.0361 +/- 0.0141. The mean elimination half-life, AUC (the area under the curve) and clearance were 22.5 +/- 9.9 h (range from 9.6 to 50.4 h), 16.33 +/- 5.52 mmoll-1h (8.69 to 31.81 mmoll-1 h), and 1.65 +/- 0.53 1h-1 (0.76 to 2.28 1h-1) or 28.59 +/- 9.58 ml/kg-1 h-1, respectively. There were no statistically significant differences in beta, AUC and clearance between Taiwanese/Chinese and Danish results. The possibility of lowering the traditional prophylactic therapeutic range of lithium to around 0.5-0.8 mmol/L is supported by the results of this study.

Linkage of two human pregnancy-specific beta 1-glycoprotein genes: one is associated with hydatidiform mole.

A genomic clone containing two linked human pregnancy-specific beta 1-glycoprotein (PS beta G) genes has been isolated and characterized. The two genes are arranged in the same 5'----3' orientation; the 3' region (including the A2 and B-C exons) of the upstream gene, PSGGA, is linked to the 5' region (including the 5'/L and L/N exons) of PSGGB, the downstream gene. Depending upon the domains compared, PSGGA and PSGGB share 92-98% nucleotide and 86-95% amino acid sequence identity with PSG93, the most abundant PS beta G transcript. The 3' exon (B-C) of PSGGA contains four alternative splice sites and three polyadenylylation sites, which account for the 3' heterogeneity previously reported in the PS beta G family. Each of the predicted PSGGA-encoded proteins would have a different carboxyl terminus. PSGGB corresponds to the previously identified cDNA PSG6, which encodes proteins containing a 34-amino acid leader peptide and a 108-amino acid N domain, which is one amino acid shorter than the majority of PS beta G N domains. Additionally, the PSGGB-encoded proteins contain the cell-surface recognition tripeptide Arg-Gly-Asp, shared by several previously reported PS beta Gs as deduced from cDNA sequences. Northern blot hybridization performed with a PSGGB-specific oligonucleotide probe to the N domain revealed that PSGGB or a PSGGB-like gene encodes a major 1.7-kilobase mRNA in hydatidiform mole tissues and a major 2.0-kilobase mRNA in term placenta tissues. Moreover, the PSGGB-specific probe hybridized most strongly with mRNA from molar trophoblastic tissue, suggesting that the PSGGB-like species may be the gene preferentially expressed in gestational trophoblastic disease. Additionally, the sequence of a 2315-base-pair PS beta G cDNA (PSG95) that contains an N-A1-A2-B2-C domain arrangement is reported. The coding region of PSG95 is identical to the previously reported cDNA clones PSG1d and FL-NCA, but PSG95 contains an additional 518 and 523 base pairs in the 3' end as compared with PSG1d and FL-NCA, respectively.

Subclinical lithium neurotoxicity: correlation of neural conduction abnormalities and serum lithium level in manic-depressive patients with lithium treatment.

Nerve conduction velocities (NCVs) and multimodality evoked potentials were studies in 28 manic-depressive patients under lithium prophylaxis with serum lithium levels between 0.320 and 0.980 mEq/L. Slowing of motor and sensory NCVs and prolonged central neural conduction times obtained from somatosensory and brainstem auditory evoked potentials were found to correlate with serum lithium levels. Lithium-induced changes in cell membrane conductivity and in the synaptic transmission are considered responsible for the neurotoxic effects of lithium.

Haloperidol and reduced haloperidol plasma levels in Chinese vs. non-Chinese psychiatric patients.

Haloperidol and reduced haloperidol plasma concentrations were measured in age-matched Chinese and non-Chinese patients (n = 32). Steady-state plasma concentrations were obtained 10-12 hours after the bedtime dose. Haloperidol and reduced haloperidol concentrations were measured by liquid chromatography and radioimmunoassay. Haloperidol plasma concentrations did not significantly differ between the populations, but reduced haloperidol levels were 3 times greater in non-Chinese patients than in Chinese patients. The incidence of extrapyramidal side effects was higher in Chinese patients (18 vs. 10), while non-Chinese patients with extrapyramidal symptoms had higher reduced haloperidol plasma levels. Logistic regression analysis revealed that ethnicity and reduced haloperidol/haloperidol ratios were important variables in predicting extrapyramidal symptoms. These results suggest that the metabolism and disposition of haloperidol and reduced haloperidol could differ among ethnic populations.