Oligonucleotide IMT504 Improves Glucose Metabolism and Controls Immune Cell Mediators in Female Diabetic NOD Mice.

Type 1 diabetes occurs as a consequence of progressive autoimmune destruction of beta cells. A potential treatment for this disease should address the immune attack on beta cells and their preservation/regeneration. The objective of this study was to elucidate whether the immunomodulatory synthetic oligonucleotide IMT504 was able to ameliorate diabetes in NOD mice and to provide further understanding of its mechanism of action. We found that IMT504 restores glucose homeostasis in a diabetes mouse model similar to human type 1 diabetes, by regulating expression of immune modulatory factors and improving beta cell function. IMT504 treatment markedly improved fasting glycemia, insulinemia, and homeostatic model assessment of beta cell function (HOMA-Beta cell) index. Moreover, this treatment increased islet number and decreased apoptosis, insulitis, and CD45+ pancreas-infiltrating leukocytes. In a long-term treatment, we observed improvement of glucose metabolism up to 9 days after IMT504 cessation and increased survival after 15 days of the last IMT504 injection. We postulate that interleukin (IL)-12B (p40), possibly acting as a homodimer, and Galectin-3 (Gal-3) may function as mediators of this immunomodulatory action. Overall, these results validate the therapeutic activity of IMT504 as a promising drug for type 1 diabetes and suggest possible downstream mediators of its immunomodulatory effect.

Dysregulated mitophagy and mitochondrial organization in optic atrophy due to OPA1 mutations.

OBJECTIVE: To investigate mitophagy in 5 patients with severe dominantly inherited optic atrophy (DOA), caused by depletion of OPA1 (a protein that is essential for mitochondrial fusion), compared with healthy controls. METHODS: Patients with severe DOA (DOA plus) had peripheral neuropathy, cognitive regression, and epilepsy in addition to loss of vision. We quantified mitophagy in dermal fibroblasts, using 2 high throughput imaging systems, by visualizing colocalization of mitochondrial fragments with engulfing autophagosomes. RESULTS: Fibroblasts from 3 biallelic OPA1(-/-) patients with severe DOA had increased mitochondrial fragmentation and mitochondrial DNA (mtDNA)-depleted cells due to decreased levels of OPA1 protein. Similarly, in siRNA-treated control fibroblasts, profound OPA1 knockdown caused mitochondrial fragmentation, loss of mtDNA, impaired mitochondrial function, and mitochondrial mislocalization. Compared to controls, basal mitophagy (abundance of autophagosomes colocalizing with mitochondria) was increased in (1) biallelic patients, (2) monoallelic patients with DOA plus, and (3) OPA1 siRNA-treated control cultures. Mitophagic flux was also increased. Genetic knockdown of the mitophagy protein ATG7 confirmed this by eliminating differences between patient and control fibroblasts. CONCLUSIONS: We demonstrated increased mitophagy and excessive mitochondrial fragmentation in primary human cultures associated with DOA plus due to biallelic OPA1 mutations. We previously found that increased mitophagy (mitochondrial recycling) was associated with visual loss in another mitochondrial optic neuropathy, Leber hereditary optic neuropathy (LHON). Combined with our LHON findings, this implicates excessive mitochondrial fragmentation, dysregulated mitophagy, and impaired response to energetic stress in the pathogenesis of mitochondrial optic neuropathies, potentially linked with mitochondrial mislocalization and mtDNA depletion.

Proposed mechanisms for oligonucleotide IMT504 induced diabetes reversion in a mouse model of immunodependent diabetes.

Type 1 diabetes (T1D) originates from autoimmune ß-cell destruction. IMT504 is an immunomodulatory oligonucleotide that increases mesenchymal stem cell cloning capacity and reverts toxic diabetes in rats. Here, we evaluated long-term (20 doses) and short-term (2-6 doses) effects of IMT504 (20 mg·kg(-1)·day(-1) sc) in an immunodependent diabetes model: multiple low-dose streptozotocin-injected BALB/c mice (40 mg·kg(-1)·day(-1) ip for 5 consecutive days). We determined blood glucose, glucose tolerance, serum insulin, islet morphology, islet infiltration, serum cytokines, progenitor cell markers, immunomodulatory proteins, proliferation, apoptosis, and islet gene expression. IMT504 reduced glycemia, induced ß-cell recovery, and impaired islet infiltration. IMT504 induced early blood glucose decrease and infiltration inhibition, increased ß-cell proliferation and decreased apoptosis, increased islet indoleamine 2,3-dioxygenase (IDO) expression, and increased serum tumor necrosis factor and interleukin-6 (IL-6). IMT504 affected islet gene expression; preproinsulin-2, proglucagon, somatostatin, nestin, regenerating gene-1, and C-X-C motif ligand-1 cytokine (Cxcl1) increased in islets from diabetic mice and were decreased by IMT504. IMT504 downregulated platelet endothelial cell adhesion molecule-1 (Pecam1) in islets from control and diabetic mice, whereas it increased regenerating gene-2 (Reg2) in islets of diabetic mice. The IMT504-induced increase in IL-6 and islet IDO expression and decreased islet Pecam1 and Cxcl1 mRNA expression could participate in keeping leukocyte infiltration at bay, whereas upregulation of Reg2 may mediate ß-cell regeneration. We conclude that IMT504 effectively reversed immunodependent diabetes in mice. Corroboration of these effects in a model of autoimmune diabetes more similar to human T1D could provide promising results for the treatment of this disease.

Multisession Radiosurgery for Sellar and Parasellar Benign Meningiomas: Long-term Tumor Growth Control and Visual Outcome.

BACKGROUND: Concern about radiation-induced optic neuropathy (RION) has governed recent thinking about the role of radiation therapy in the treatment of meningiomas involving the anterior optic pathways. Despite this concern, during the last few years, the use of radiosurgery for such lesions has increased steadily. OBJECTIVE: To define both the tumor control rate and the risk of RION over a long-term follow-up period in a large cohort of patients treated with multisession radiosurgery. METHODS: The local control and visual outcome of 143 patients who underwent multisession radiosurgery (mRS) were evaluated. Neurological outcome was also analyzed. The data for the present study were obtained from a prospectively maintained database. RESULTS: The mean follow-up was 44 months (range, 12-113 months). All patients underwent mRS. The median prescription dose was 25 Gy delivered in 3 to 5 fractions. The prescription isodose, which typically encompassed at least 95% of the tumor, ranged from 65% to 86% (median, 80%). The mean tumor volume was 11.0 cm (range, 0.1-126.3 cm; median, 8 cm). The progression-free survival at 3, 5, and 8 years was 100%, 93%, and 90%, respectively. Compared with baseline, visual function improved in 36% of patients, whereas 7.4% experienced a worsening in visual function (5.1% excluding the patients with progressive disease). CONCLUSION: Good local control rate and a low risk of RION indicate that mRS is a safe and effective treatment option in cases of large meningiomas.

Visual outcome after fronto-temporo-orbito-zygomatic approach combined with early extradural and intradural optic nerve decompression in tuberculum and diaphragma sellae meningiomas.

OBJECT: The surgical challenge of the treatment of tuberculum (TSMs) and diaphragma sellae meningiomas (DSMs) is to preserve or improve the visual function. Extradural and intradural optic nerve decompression should reduce surgical trauma of the nerve achieving a good visual result. METHODS: We reported 37 consecutive TSMs and DSMs operated through fronto-temporo-orbito-zygomatic approach with extradural unroofing of the optical canal and early intradural incision of the dural sheath. Visual data were recorded measuring the visual impairment score (VIS), the visual acuity (VA), the visual field (VF) and the postoperative improvement. RESULTS: A good visual outcome (VIS improved or unchanged) was obtained in 97.2% of patients (35/36). The evaluation of 72 eyes showed a good outcome (VA and VF unchanged or improved) in 98.6% (71/72 eyes). The degree of preoperative VA and VF impairment was the only factor correlating with the postoperative improvement of VA (P<.001 and P=.018) and VF defect (P<.001). Worsening of visual function occurred in 1/37 patient (2.7%). CONCLUSION: Using this surgical technique we achieved a high improvement rate of visual defects and a low frequency of worsening.

Prognostic factors of visual field improvement after trans-sphenoidal approach for pituitary macroadenomas: review of the literature and analysis by quantitative method.

The objective of the study was to evaluate the preoperative visual field defect, the postoperative outcome and the possible prognostic factors in patients with pituitary macroadenoma, using a quantitative method (the mean deviation = MD), and to review the literature. A total of 73 patients, operated trough trans-sphenoidal approach, were selected, and data in single eyes were analysed by calculating the frequency and the degree of postoperative improvement (relative improvement). The visual field defect improved in 95.7% of eyes: The recovery was complete in 48.9% and partial in 46.8%. Multivariate logistic regression showed that factors, independently predictive for complete recovery, were as follows: low preoperative MD absolute value (p = 0.008), low cranio-caudal diameter of tumour (p = 0.02) and young age (p = 0.0001). The mean relative improvement in visual field defect (dMD%) was correlated with the preoperative visual acuity (p = 0.0001) and inversely related with the preoperative MD (p = 0.007) and the age (p = 0.017). The relative improvement was higher in tumours with a smaller cranio-caudal diameter (p = 0.0185). In conclusion, using a quantitative method, we can measure the degree of the postoperative visual field defect improvement. Predictive factors for a complete recovery were good preoperative visual function, young age and low cranio-caudal tumour.

Multisession radiosurgery for optic nerve sheath meningiomas--an effective option: preliminary results of a single-center experience.

BACKGROUND: Traditional treatment options for optic nerve sheath meningiomas (ONSMs) include observation, surgery, and radiotherapy, but to date none of these has become the clear treatment of choice. OBJECTIVE: To evaluate the effectiveness and safety of multisession radiosurgery for ONSMs. METHODS: From May 2004 to June 2008, 21 patients with ONSMs were treated by radiosurgery using the frameless CyberKnife system. Patient age ranged from 36 to 73 years (mean, 54 years). All patients were treated using multisession radiosurgery, with 5 fractions of 5 Gy each to a total dose of 25 Gy prescribed to the 75% to 85% isodose line. Patients were evaluated for tumor growth control and visual function. RESULTS: The median pretreatment tumor volume was 2.8 mL (range, 0.3-23 mL). The mean follow-up was 30 months (range, 11-68 months). All patients tolerated treatment well, with only 1 patient in whom a mild optic neuropathy developed (which remitted after systemic steroid therapy). No other acute or late radiation-induced toxicities were observed. No patients showed ONSM progression on follow-up magnetic resonance imaging. Two patients (10%) had a partial response. No patients had worsening of visual function; visual function was stable in 65% and improved in 35% of patients. CONCLUSION: Multisession radiosurgery for ONSMs was found to be safe and effective. The preliminary results from this study, in terms of growth control, visual function improvement, and toxicity, are quite promising. Further investigations are warranted.

Ocular adnexal lymphoma: diffusion-weighted mr imaging for differential diagnosis and therapeutic monitoring.

PURPOSE: To describe the magnetic resonance (MR) imaging and diffusion-weighted (DW) imaging features of ocular adnexal lymphomas (OALs), to determine the diagnostic accuracy of apparent diffusion coefficient (ADC) for discriminating OALs from other orbital mass lesions, and to assess whether variations in ADC constitute a reliable biomarker of OAL response to therapy. MATERIALS AND METHODS: Institutional ethical committee approval and informed consent were obtained. In this prospective study, 114 white subjects (65 females and 49 males) were enrolled. Thirty-eight patients with histopathologically proved OAL underwent serial MR and DW imaging examination of the orbits. ADCs of OALs were compared with those of normal orbital structures, obtained in 18 healthy volunteers, and other orbital mass lesions, prospectively acquired in 58 patients (20 primary non-OAL neoplasms, 15 vascular benign lesions, 12 inflammatory lesions, 11 metastases). Interval change in ADC of OALs before and after treatment was analyzed in 29 patients. Analysis of covariance and a paired t test were used for statistical analysis. RESULTS: Baseline ADCs in OALs were lower than those in normal structures and other orbital diseases (P < .001). An ADC threshold of 775 x 10(-6) mm(2)/sec resulted in 96% sensitivity, 93% specificity, 88% positive predictive value, 98.2% negative predictive value, and 94.4% accuracy in OAL diagnosis. Following appropriate treatment, 10 (34%) of 29 patients showed OAL volumetric reduction, accompanied (n = 7) or preceded (n = 3) by an increase in ADC (P = .005). Conversely, a further reduction of ADC was observed in the seven patients who experienced disease progression (P < .05). CONCLUSION: ADC permits accurate diagnosis of OALs. Interval change in ADC after therapy represents a helpful tool for predicting therapeutic response.

Visual loss secondary to orbital apex invasion as the first manifestation of recurrent nasopharyngeal carcinoma.

A 51-year-old white man was referred for evaluation of visual loss in the right eye caused by an apical orbital lesion. His medical history was positive for "lymphoepithelial carcinoma" of the nasopharynx successfully treated with radiotherapy 6 years previously. Cranial CT showed a diffuse orbital mass extending from the pterygopalatine fossa, infiltrating the inferior orbital fissure, the orbital apex, and the cranial cavity. Results from an incisional biopsy of the lesion were consistent with the diagnosis of nasopharyngeal carcinoma, nonkeratinizing lymphoepithelial variant of squamous cell carcinoma. The patient underwent stereotactic radiosurgery, which arrested the tumor progression. Orbitocranial recurrence of nasopharyngeal carcinoma is rare and ocular symptoms may be the first manifestation of the disease.

Retinal nerve fiber layer evaluation by optical coherence tomography in Leber's hereditary optic neuropathy.

PURPOSE: To study retinal nerve fiber layer (RNFL) thickness by optical coherence tomography (StratusOCT) in patients with Leber's hereditary optic neuropathy (LHON). DESIGN: Cross-sectional study. PARTICIPANTS AND/OR CONTROLS: Thirty-eight patients with LHON were analyzed and compared with an age-matched control group of 75 patients. Patients with LHON were classified as having early LHON (E-LHON, n = 8) when the duration of the disease was shorter than 6 months and atrophic LHON (A-LHON, n = 30) when the duration was longer than 6 months. METHODS: The fast RNFL thickness (3.4) scan acquisition protocol was used. MAIN OUTCOME MEASURE: Retinal nerve fiber layer thickness as measured by StratusOCT. RESULTS: Compared with the control group, eyes with E-LHON showed a thicker RNFL in the 360 degrees average measurement (P<0.01) and in the superior (P<0.01), nasal (P<0.05), and inferior quadrants (P<0.05); no significant changes were detected in the temporal quadrant. Eyes with A-LHON revealed a thinner RNFL in all measurements (P<0.001); the fibers of the nasal quadrant showed the lowest amount of reduction (38% vs. 42%-49.8% in the other quadrants). In cases with A-LHON and visual recovery, RNFL was significantly thicker in all measurements (P<0.001), except the temporal quadrant, with respect to A-LHON without visual recovery. CONCLUSIONS: On the basis of OCT data, the RNFL is thickened in E-LHON and severely thinned in A-LHON. RNFL is likely to be partially preserved in A-LHON with visual recovery. The temporal fibers (papillomacular bundle) are the first and most severely affected; the nasal fibers seem to be partially spared in the late stage of the disease.

Retinal nerve fiber layer evaluation by optical coherence tomography in unaffected carriers with Leber's hereditary optic neuropathy mutations.

PURPOSE: To study retinal nerve fiber layer (RNFL) thickness by optical coherence tomography (OCT) in unaffected carriers with Leber's hereditary optic neuropathy (LHON) mutations. DESIGN: Cross-sectional study. PARTICIPANTS: Sixty-six unaffected carriers (44 females and 22 males) were analyzed and compared with an age-matched control group of 70 patients (40 females and 30 males). The statistical analysis was performed after grouping both the patients and the control group on the basis of gender and, for unaffected carriers only, mitochondrial DNA mutation. METHODS: The Fast RNFL Thickness (3.4) scan acquisition protocol was used. MAIN OUTCOME MEASURE: Retinal nerve fiber layer thickness as measured by OCT. RESULTS: With respect to the control group, unaffected male carriers showed a thicker RNFL in the temporal and inferior quadrants and in the 360 degrees average measurement (P = 0.025, P = 0.03, and P = 0.018, respectively). These differences reached statistical significance in subjects carrying the 11778 mutation, whereas only a trend was detected in those with the 3460 mutation. Unaffected female carriers had an increased thickness in the temporal quadrant when compared with the control group (P = 0.003) and no differences in the other measurements. The increase in temporal sectors was statistically significant in females with the 11778 mutation, whereas a trend was detected in those with the 3460 mutation. CONCLUSIONS: A thickening of the temporal fibers was detected in all subgroups of unaffected carriers. This is the first evidence indicating the preferential involvement of the papillomacular bundle in subclinical LHON. This notion previously was based on the early loss of fibers from the temporal quadrant in acute LHON and the selective loss of small-caliber fibers at histopathology. Our study also revealed that males have a more diffuse involvement than females.

Gamma knife surgery for treatment of residual nonfunctioning pituitary adenomas after surgical debulking.

OBJECT: Radiation therapy diminishes the risk of recurrence of incompletely removed nonfunctioning pituitary adenoma (NPA). The authors evaluated the efficacy and safety of gamma knife surgery (GKS) in patients with residual NPA following surgical debulking of the tumor. METHODS: Fifty-four patients, 26 men and 28 women, ranging in age from 29 to 72 years underwent gamma knife treatment. Baseline and follow-up studies involved magnetic resonance imaging, hormone evaluation, and neuroophthalmological examination 6 and 12 months after GKS and at yearly intervals thereafter. The mean follow up after GKS was 41.1 +/- 3.1 months. Two of 52 patients undergoing follow up had a recurrence 40 and 49 months after GKS. In both of these patients the treated lesion had reduced in size, but a new lesion appeared in the contralateral side of the sella turcica. The recurrence-free interval at 5 years was 88.2% (95% confidence interval 72.6-100%). Tumor volume decreased from a baseline value of 2.3 +/- 0.2 to 1.7 +/- 0.2 cm3 at the last follow up (p < 0.001). Twenty-two patients (42.3%) had a 20% or greater reduction in tumor volume. The administered radiation dose had been significantly higher in patients who experienced tumor reduction. Visual function and motility did not deteriorate in any patient. New cases of hypogonadism, hypothyroidism, and hypoadrenalism occurred in 12.5, 8.6, and 2.3%, respectively, of assessable patients at risk. CONCLUSIONS: Gamma knife surgery was effective in controlling the growth of residual NPA after previously performed maximal surgical debulking. The major advantage of GKS compared with fractionated radiotherapy seems to be a lower risk of side effects, especially a lower risk of hypopituitarism.

Irreversible disability and tissue loss in multiple sclerosis: a conventional and magnetization transfer magnetic resonance imaging study of the optic nerves.

OBJECTIVES: To assess, by magnetic resonance imaging, the volumes and magnetization transfer ratio (MTR) values of optic nerves (ONs) from patients with multiple sclerosis (MS) who had incomplete or no visual recovery after optic neuritis; and to compare these quantities with those derived from ONs from patients with MS who showed a marked clinical recovery after optic neuritis, ONs from healthy volunteers, and ONs from patients with Leber hereditary optic neuropathy (LHON). METHODS: Conventional and magnetization transfer magnetic resonance images of the ONs were obtained from 30 patients with MS, 18 healthy volunteers, and 10 patients with LHON. The ON from patients with MS were classified as clinically unaffected (n = 18); clinically affected with recovery (n = 20; visual acuity > or =20/25 at least 6 months after optic neuritis); and clinically affected with incomplete or no recovery (n = 22; visual acuity <20/25 at least 6 months after optic neuritis). The ON volumes and MTR values were measured. RESULTS: Volumes (P =.002) and MTR values (P<.001) of the ONs from patients with MS and incomplete or no recovery were both lower than those of the ONs from patients with MS and recovery, but not different from those of the ONs from patients with LHON. Volumes and MTR values of the affected ONs from patients with MS and recovery did not differ from those of clinically unaffected ONs, which were similar to those of healthy volunteers. CONCLUSION: These findings suggest that, in patients with MS, neurodegeneration is associated with persistent functional deficits secondary to incomplete recovery from relapses.