Alterations in DNA methylation rates of brain-derived neurotrophic factor in patients with schizophrenia

Background and objectives: Schizophrenia (SZ) is one of the most disabling mental illness and the elucidation of diagnostic and therapeutic biomarkers are required. Recent studies investigating the brain morphology, the gene expression profile, and the genetic epidemiology have suggested the involvement of Brain-derived neurotrophic factor (BDNF) and its epigenetic regulation in the pathophysiology of SZ. The current study was conducted to determine the association of DNA methylation of the BDNF gene with the diagnosis or with the characteristics of patients with SZ.MethodsWe analyzed genomic DNA from peripheral blood of 22 patients with SZ and 22 healthy subjects. The DNA methylation rates (DMRs) of the CpG island at the promoter of exón I of the BDNF gene were measured using EpiTYPER® and the MassARRAY® system (Agena Biosciences). We examined the validity of the methylation profiles as a diagnostic biomarker for SZ by clustering analyses, differences in DMRs between patients and healthy controls, and the relationship between DMRs and patient characteristics.ResultsThe clustering analysis failed to distinguish between healthy controls and patients with SZ, though the DMRs of 4 CpG units were significantly different between these two groups. Whereas the DMR of one CpG (CpG 28) was significantly correlated with the amount of daily antipsychotics, there was no influence of age, severity, or duration of illness on the DMRs of the BDNF gene.ConclusionDespite the small number of subjects, our results suggest the involvement of the changes in DMRs of the BDNF gene in the pathophysiology of SZ. (AU)

Evaluation of apocynin in vitro on high glucose-induced oxidative stress on tenocytes.

AIMS: The purpose of this study was to evaluate the in vitro effects of apocynin, an inhibitor of nicotinamide adenine dinucleotide phosphate oxidase (NOX) and a downregulator of intracellular reactive oxygen species (ROS), on high glucose-induced oxidative stress on tenocytes. METHODS: Tenocytes from normal Sprague-Dawley rats were cultured in both control and high-glucose conditions. Apocynin was added at cell seeding, dividing the tenocytes into four groups: the control group; regular glucose with apocynin (RG apo+); high glucose with apocynin (HG apo+); and high glucose without apocynin (HG apo-). Reactive oxygen species production, cell proliferation, apoptosis and messenger RNA (mRNA) expression of NOX1 and 4, and interleukin-6 (IL-6) were determined in vitro. RESULTS: Expression of NOX1, NOX4, and IL-6 mRNA in the HG groups was significantly higher compared with that in the RG groups, and NOX1, NOX4, and IL-6 mRNA expression in the HG apo+ group was significantly lower compared with that in the HG apo- group. Cell proliferation in the RG apo+ group was significantly higher than in the control group and was also significantly higher in the HG apo+ group than in the HG apo- group. Both the ROS accumulation and the amounts of apoptotic cells in the HG groups were greater than those in the RG groups and were significantly less in the HG apo+ group than in the HG apo- group. CONCLUSION: Apocynin reduced ROS production and cell death via NOX inhibition in high-glucose conditions. Apocynin is therefore a potential prodrug in the treatment of diabetic tendinopathy.Cite this article: Bone Joint Res 2020;9(1):23-28.

The effects of high glucose condition on rat tenocytes in vitro and rat Achilles tendon in vivo.

OBJECTIVES: The aim of this study was to investigate the effect of hyperglycaemia on oxidative stress markers and inflammatory and matrix gene expression within tendons of normal and diabetic rats and to give insights into the processes involved in tendinopathy. METHODS: Using tenocytes from normal Sprague-Dawley rats, cultured both in control and high glucose conditions, reactive oxygen species (ROS) production, cell proliferation, messenger RNA (mRNA) expression of NADPH oxidase (NOX) 1 and 4, interleukin-6 (IL-6), matrix metalloproteinase (MMP)-2, tissue inhibitors of matrix metalloproteinase (TIMP)-1 and -2 and type I and III collagens were determined after 48 and 72 hours in vitro. In an in vivo study, using diabetic rats and controls, NOX1 and 4 expressions in Achilles tendon were also determined. RESULTS: In tenocyte cultures grown under high glucose conditions, gene expressions of NOX1, MMP-2, TIMP-1 and -2 after 48 and 72 hours, NOX4 after 48 hours and IL-6, type III collagen and TIMP-2 after 72 hours were significantly higher than those in control cultures grown under control glucose conditions. Type I collagen expression was significantly lower after 72 hours. ROS accumulation was significantly higher after 48 hours, and cell proliferation after 48 and 72 hours was significantly lower in high glucose than in control glucose conditions. In the diabetic rat model, NOX1 expression within the Achilles tendon was also significantly increased. CONCLUSION: This study suggests that high glucose conditions upregulate the expression of mRNA for NOX1 and IL-6 and the production of ROS. Moreover, high glucose conditions induce an abnormal tendon matrix expression pattern of type I collagen and a decrease in the proliferation of rat tenocytes.Cite this article: Y. Ueda, A. Inui, Y. Mifune, R. Sakata, T. Muto, Y. Harada, F. Takase, T. Kataoka, T. Kokubu, R. Kuroda. The effects of high glucose condition on rat tenocytes in vitro and rat Achilles tendon in vivo. Bone Joint Res 2018;7:362-372. DOI: 10.1302/2046-3758.75.BJR-2017-0126.R2.

Deletion of Rapgef6, a candidate schizophrenia susceptibility gene, disrupts amygdala function in mice.

In human genetic studies of schizophrenia, we uncovered copy-number variants in RAPGEF6 and RAPGEF2 genes. To discern the effects of RAPGEF6 deletion in humans, we investigated the behavior and neural functions of a mouse lacking Rapgef6. Rapgef6 deletion resulted in impaired amygdala function measured as reduced fear conditioning and anxiolysis. Hippocampal-dependent spatial memory and prefrontal cortex-dependent working memory tasks were intact. Neural activation measured by cFOS phosphorylation demonstrated a reduction in hippocampal and amygdala activation after fear conditioning, while neural morphology assessment uncovered reduced spine density and primary dendrite number in pyramidal neurons of the CA3 hippocampal region of knockout mice. Electrophysiological analysis showed enhanced long-term potentiation at cortico-amygdala synapses. Rapgef6 deletion mice were most impaired in hippocampal and amygdalar function, brain regions implicated in schizophrenia pathophysiology. The results provide a deeper understanding of the role of the amygdala in schizophrenia and suggest that RAPGEF6 may be a novel therapeutic target in schizophrenia.

A comparison of 3-D computed tomography versus 2-D radiography measurements of ulnar variance and ulnolunate distance during forearm rotation.

Positive ulnar variance is associated with ulnar impaction syndrome and ulnar variance is reported to increase with pronation. However, radiographic measurement can be affected markedly by the incident angle of the X-ray beam. We performed three-dimensional (3-D) computed tomography measurements of ulnar variance and ulnolunate distance during forearm rotation and compared these with plain radiographic measurements in 15 healthy wrists. From supination to pronation, ulnar variance increased in all cases on the radiographs; mean ulnar variance increased significantly and mean ulnolunate distance decreased significantly. However on 3-D imaging, ulna variance decreased in 12 cases on moving into pronation and increased in three cases; neither the mean ulnar variance nor mean ulnolunate distance changed significantly. Our results suggest that the forearm position in which ulnar variance increased varies among individuals. This may explain why some patients with ulnar impaction syndrome complain of wrist pain exacerbated by forearm supination. It also suggests that standard radiographic assessments of ulnar variance are unreliable.

Limited effect of testosterone treatment for erectile dysfunction caused by high-estrogen levels in rats.

Some studies suggest that high-estrogen levels lead to erectile dysfunction (ED); high-estrogen levels are known to decrease testosterone levels. However, no study has examined whether testosterone replacement can improve the ED induced by high-estrogen levels. We investigated the effects of testosterone on ED caused by high-estrogen levels in rats. Rats were distributed in the following groups: (1) control (vehicle for 2 weeks), (2) the estrogen-treated group (ES; estradiol (3 µg kg(-1) day(-1)) for 2 weeks), and (3) the estrogen- and testosterone-treated group (ES+TE; estradiol (3 µg kg(-1) day(-1)) and testosterone (3 mg kg(-1) day(-1)) for 2 weeks). We measured smooth muscle function via isometric tension and erectile function by measuring the intracavernosal pressure on cavernous nerve stimulation. In the ES group, the contraction of the corpus cavernosum smooth muscle increased in response to noradrenalin, and its relaxation decreased in response to the nitric oxide donor, sodium nitroprusside. Further, the erectile function was significantly decreased. In the ES+TE group, neither smooth muscle function nor erectile function was significantly improved. In conclusion, a high-estrogen milieu affected erectile function in rats, and testosterone treatment did not improve the ED caused by high-estrogen levels.

Preventive and curative effects of radon inhalation on chronic constriction injury-induced neuropathic pain in mice.

BACKGROUND: Radon therapy is clinically useful for the treatment of pain-related diseases. However, there have been no studies regarding the effects of radon inhalation on neuropathic pain. In this study, we aimed to determine whether radon inhalation actually induced a remission of neuropathic pain and improved the quality of life. METHODS: First, we investigated the antinociceptive effects of radon inhalation in the chronic constriction injury (CCI) model of neuropathic pain. We evaluated pain behaviour in mice before and after CCI surgery, using von Frey test. Pretreated mice received CCI surgery immediately after 24-h inhalation of radon at background (BG) concentration (c. 19 Bq/m(3) ), or at a concentration of 1000 or 2000 Bq/m(3) , and post-treated mice inhaled similar levels of radon 2 days after CCI surgery. RESULTS: CCI surgery induced mechanical allodynia and hyperalgesia on a plantar surface of mice, as assessed using von Frey test, and 2000 Bq/m(3) radon inhalation alleviated hyperalgesic conditions 22-37% compared to BG level concentration. Concurrently, CCI surgery increased norepinephrine (NE), tumour necrosis factor-alpha (TNF-α) and nitric oxide (NO) concentrations in plasma, and leukocyte migration in paws. Furthermore, CCI-induced neuropathy reduced superoxide dismutase (SOD) activity. Treatment with radon inhalation, specifically at a concentration of 2000 Bq/m(3) , produced antinociceptive effects, i.e., lowered plasma TNF-α, NE and NO levels and restored SOD activity, as well as pain-related behaviour. CONCLUSIONS: This study showed that inhalation of 2000 Bq/m(3) radon prevented and alleviated CCI-induced neuropathic pain in mice.

Palmar reconstruction of the triangular fibrocartilage complex for instability of the distal radioulnar joint: a biomechanical study.

We developed a new triangular fibrocartilage complex reconstruction technique for distal radioulnar joint instability in which the palmar portion of the triangular fibrocartilage complex was predominantly reconstructed, and evaluated whether such reconstruction can restore stability of the distal radioulnar joint in seven fresh cadaver upper extremities. Distal radioulnar joint instability was induced by cutting all soft-tissue stabilizers around the distal ulna. Using a palmar approach, a palmaris longus tendon graft was sutured to the remnant of the palmar radioulnar and ulnocarpal ligaments. The graft was then passed through a bone tunnel created at the fovea and was sutured. Loads were applied to the radius, and dorsopalmar displacements of the radius relative to the ulna were measured using an electromagnetic tracking device in neutral rotation, 60° supination and 60° pronation. We compared the dorsopalmar displacements before sectioning, before reconstruction and after reconstruction. Dorsopalmar instability produced by sectioning significantly improved in all forearm positions after reconstruction.

Suppression of streptozotocin-induced type-1 diabetes in mice by radon inhalation.

We examined the protective effect of radon inhalation on streptozotocin (STZ)-induced type-1 diabetes in mice. Mice inhaled radon at concentrations of 1000, 2500, and 5500 Bq/m3 for 24 hours before STZ administration. STZ administration induced characteristics of type-1 diabetes such as hyperglycemia and hypoinsulinemia; however, radon inhalation at doses of 1000 and 5500 Bq/m3 significantly suppressed the elevation of blood glucose in diabetic mice. Serum insulin was significantly higher in mice pre-treated with radon at a dose of 1000 Bq/m3 than in mice treated with a sham. In addition, superoxide dismutase activities and total glutathione contents were significantly higher and lipid peroxide was significantly lower in mice pre-treated with radon at doses of 1000 and 5500 Bq/m3 than in mice treated with a sham. These results were consistent with the result that radon inhalation at 1000 and 5500 Bq/m3 suppressed hyperglycemia. These findings suggested that radon inhalation suppressed STZ-induced type-1 diabetes through the enhancement of antioxidative functions in the pancreas.

Movement strategies during car transfers in individuals with tetraplegia: a preliminary study.

STUDY DESIGN: Three-dimensional kinematic analysis of car transfer (CT) movement in four adult males with C6 tetraplegia. OBJECTIVES: The aim of the present study was to assess the normal transfer technique movement from a wheelchair to a car (that is, CT) in subjects with tetraplegia. A better understanding of CT movement is invaluable knowledge for spinal cord injury rehabilitation. This type of knowledge will improve rehabilitation programs so that patients with tetraplegia will have greater societal participation. SETTING: School of Comprehensive Rehabilitation, Osaka Prefecture University, Osaka, Japan. METHODS: Four adult males with C6 tetraplegia, an impairment grade of A according to the American Spinal Injury Association guidelines, took part in the study. The subjects used their own wheelchair and car in our assessments of their CT movement technique. Movements were assessed using a three-dimensional video analysis system with six digital video cameras. CT data, which included lateral displacement of the head and buttocks, and angular displacement of neck flexion and trunk forward inclination, were collected and correlation coefficients were calculated. RESULTS: All four subjects demonstrated negative correlations in lateral displacements greater than 0.70. As for correlation coefficients of angular displacement, two subjects demonstrated negative correlations (r = -0.98 and r = -0.77) and one subject demonstrated a positive correlation (r = 0.75). The neck flexion and trunk forward inclination strategy was different among the four subjects. CONCLUSIONS: Each subject with C6 tetraplegia demonstrated different strategies during CT movement.

Radioactivity of 210Pb in Japanese cigarettes and radiation dose from smoking inhalation.

It is well known that cigarette tobaccos contain naturally occurring radioactive nuclides such as (210)Pb and (210)Po. In many countries, the radioactivity of tobaccos has been measured to estimate the effective dose from smoking inhalation. The present study covered 24 cigarette brands including the top 20 of sales in Japan between April 2008 and March 2009. The activity concentrations of (210)Pb were measured by gamma-ray spectrometry, and then those of its progeny ((210)Po) were evaluated assuming the radioactive equilibrium between the two nuclides. Their concentrations were in the range of 2-14 mBq cigarette(-1) with an arithmetic mean of 8±3 mBq cigarette(-1). The annual committed effective doses were also calculated, based on the scenario that a smoker consumes 20 cigarettes a day. The average doses from (210)Pb and (210)Po inhalations were 22±9 and 68±27 µSv y(-1), respectively.

Bulk and surface magnetization of Co atoms in rutile Ti(1-x)Co(x)O(2-δ) thin films revealed by x-ray magnetic circular dichroism.

We have studied magnetism in Ti(1-x)Co(x)O(2-δ) thin films with various x and δ by soft x-ray magnetic circular dichroism (XMCD) measurements at the Co L(2, 3) absorption edges. The estimated ferromagnetic moment by XMCD was 0.15-0.24 µ(B)/Co at the surface, while in the bulk it was 0.82-2.25 µ(B)/Co, which is in the same range as the saturation magnetization of 1.0-1.5 µ(B)/Co. These results suggest an intrinsic origin of the ferromagnetism. The smaller moment of the Co atom at the surface is an indication of a magnetically dead layer of a few nanometers thick at the surface of the thin films.

Effect of co-doping of donor and acceptor impurities in the ferromagnetic semiconductor Zn(1-x)Cr(x)Te studied by soft x-ray magnetic circular dichroism.

We have performed x-ray absorption spectroscopy (XAS) and x-ray magnetic circular dichroism (XMCD) studies of the diluted ferromagnetic semiconductor Zn(1-x)Cr(x)Te doped with iodine (I) or nitrogen (N), corresponding to electron or hole doping, respectively. From the shape of the Cr 2p absorption peak in the XAS spectra, it was concluded that the Cr ions in the undoped, I-doped and lightly N-doped samples are divalent (Cr(2+)), while Cr(2+) and trivalent (Cr(3+)) coexist in the heavily N-doped sample. This result indicates that the doped nitrogen atoms act as acceptors but that doped holes are located on the Cr ions. In the magnetic field dependence of the XMCD signal at the Cr 2p absorption edge, ferromagnetic behaviors were observed in the undoped, I-doped, and lightly N-doped samples, while ferromagnetism was considerably suppressed in the heavily N-doped sample, which is consistent with the results of magnetization measurements.