Arpna Srivastava

Evaluation of Oxidative Stress Markers in Aqueous Humor of Primary Open Angle Glaucoma and Primary Angle Closure Glaucoma Patients

Abstract Purpose: The present study was designed to determine the levels of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) and non-enzymatic antioxidants (vitamins C and E) in aqueous humor of primary open angle glaucoma (POAG) and primary angle closure glaucoma (PACG) patients. Materials and Methods: In this study, aqueous humor of POAG (n = 30) and PACG (n = 30) patients was obtained. For control, aqueous humor of 30 age-matched cataract patients (n = 30) was collected. Activities of antioxidant enzymes and non-enzymatic antioxidants levels were measured spectrophotometrically. Results: A significant increase in superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities was found in aqueous humor of POAG and PACG patients as compared to cataract patients (p < 0.001). No significant changes were observed in catalase activity. The levels of vitamins C and E were significantly lower in the aqueous humor of POAG and PACG as compared to cataract patients (p < 0.001). Conclusion: These results suggest that a significant increase in oxidative stress may play a role in the pathogenesis of POAG and PACG. Determination of oxidative stress in aqueous humor may help in understanding the course of this disease, and oxidative damage might be a relevant target for both prevention and therapy.

Uveitis: Mechanisms and recent advances in therapy.

Uveitis is a sight threatening inflammatory disorder that affects all ages and remains a significant cause of visual loss. Animal models of autoimmune and inflammatory disease in the eye allow the scientist and clinician to study the basic mechanism of the disease, and serve as templates for the development of therapeutic approaches. The accumulating knowledge of the various steps that are involved in the pathogenesis make it possible to devise specific strategies that disrupt discrete stages in the process. Some of the strategies are in the process of being translated to the clinic. New technologies emerge, promising more specific and more easily applied therapies. In this review, we will concentrate specifically on mechanisms and recent advances in the therapy of uveitis.

Role of inflammation and its miRNA based regulation in epilepsy: Implications for therapy.

There is a need to develop innovative therapeutic strategies to counteract epilepsy, a common disabling neurological disorder. Despite the recent advent of additional antiepileptic drugs and respective surgery, the treatment of epilepsy remains a major challenge. The available therapies are largely based on symptoms, and these approaches do not affect the underlying disease processes and are also associated frequently with severe side effects. This is mainly because of the lack of well-defined targets in epilepsy. The discovery that inflammatory mediators significantly contribute to the onset and recurrence of seizures in experimental seizure models, as well as the presence of inflammatory molecules in human epileptogenic tissue, highlights the possibility of targeting specific inflammation related pathways to control seizures that are otherwise resistant to the available AEDs. Emerging studies suggest that miRNAs have a significant role in regulating inflammatory pathways shown to be involved in epilepsy. These miRNAs can possibly be used as novel therapeutic targets in the treatment of epilepsy as well as serve as diagnostic biomarkers of epileptogenesis. This review highlights the immunological features underlying the pathogenesis of epileptic seizures and the possible miRNA mediated approaches for drug resistant epilepsies that modulate the immune-mediated pathogenesis.

Association between angiotensin converting enzyme gene insertion/deletion polymorphism and ischemic stroke in north Indian population: a case–control study and meta-analysis

Abstract Objective: The purpose of this case–control study was to determine the relationship between angiotensin converting enzyme (ACE) insertion/deletion polymorphism and serum ACE level in north Indian patients with ischemic stroke. Methods: In the present study, 224 ischemic stroke patients and 224 age- and sex-matched control participants were recruited. Genotyping was performed using polymerase chain reaction (PCR) method. Serum ACE levels were measured by colorimetric method. Our results were integrated with other reported studies from India for a meta-analysis. Results: We observed that DD genotypes were more frequently distributed in cases (32·6%) compared with controls (26·8%). Borderline significance was observed between DD genotype and risk of small vessel disease (SVD) stroke as compared to controls (OR, 1·9; 95% CI, 0·88-4·4; P value 0·09) assuming dominant model of inheritance. The mean ACE serum level in IU/l for II, ID, and DD genotypes were 17·1 ± 7·7, 26 ± 12·4, and 51·3 ± 21 (P value < 0·001) in cases and 16·5 ± 9·4, 26·8 ± 13, and 45·19 ± 18·3 (P value < 0·001) in controls, respectively. Discussion: The results of the study show lack of significant association between ACE insertion/deletion polymorphism and ischemic stroke, however, higher risk was observed with DD genotype in small vessel disease stroke, but with borderline significance. Meta-analysis of studies from India showed that DD genotype is associated with risk of ischemic stroke.

Unidirectional whole body turning: a new lateralising sign in complex partial seizures.

Background: The lateralising significance of unidirectional whole body turning in patients with complex partial seizures (CPS) arising from the temporal lobe was evaluated. Methods: A total of 330 patients undergoing long term video-EEG study were included. “Unidirectional whole body turning” was defined as rotation of the trunk, head, and limbs by >90° and lasting >10 s. EEG correlates, MRI, and SPECT findings were compared and outcome after surgery was noted for patients with follow up data for >1 year. Results: Unidirectional whole body turning was observed in 13 patients with a mean age of 18±8 years. Concordance of the side of whole body turning with the EEG focus and MRI findings was observed in 11 of the 13 patients (84.7%) and in 26 of 28 seizures (92.8%). The six patients who underwent temporal lobectomy or resection of lesion, opposite to the direction of body turning, had good seizure outcome. Conclusion: Unidirectional whole body turning is a new lateralising sign in temporal lobe CPS with good predictive value for epileptogenic focus contralateral to the direction of turning.

Altered glutamatergic tone reveals two distinct resting state networks at the cellular level in hippocampal sclerosis

Hippocampal sclerosis (HS), the most common subset of drug-resistant epilepsy (DRE), is associated with large-scale network abnormalities, even under resting state. We studied the excitatory postsynaptic currents (EPSCs) recorded from pyramidal neurons in resected samples under resting conditions from the hippocampal and anterior temporal lobe (ATL) obtained from patients with HS (n = 14) undergoing resective surgery. We observed higher frequency and amplitude of spontaneous EPSCs in both the samples compared to non-seizure control samples. Application of tetrodotoxin (TTX) reduced the frequency of spontaneous EPSCs by 49.6 ± 4.3% and 61.8 ± 6.2% in the hippocampal and ATL samples, respectively. The magnitude of reduction caused by TTX with respect to non-seizure controls was significantly higher in the ATL samples than in the hippocampal samples. The magnitude of the change in the expression of the NR2A subunit of the NMDA receptors also varied in these two regions. Thus, the mechanism of hyperexcitabilty mediated by glutamatergic network reorganization in the hippocampal region is different from that in the ATL region of patients with HS, suggesting two independent resting-state networks at the cellular level. Taken together, these findings will improve the understanding of the broadly distributed resting-state networks in HS.

A novel duplication in the PAX6 gene in a North Indian family with aniridia

Mutations in paired box gene 6 (PAX6) are the major cause of aniridia that may be associated with several other developmental anomalies of the eye, including microcornea in rare cases. Therefore, the purpose of this study was to identify the underlying genetic cause in a two-generation North Indian family diagnosed with aniridia. All the participants enrolled in the study, including the aniridia family and 20 healthy individuals (controls), underwent a comprehensive ophthalmic examination. Mutation screening was performed for the PAX6 gene by direct sequencing of the polymerase chain reaction products. A novel PAX6 duplication in exon 5 at position c.474dupC was identified in all three affected individuals from the family but not in the unaffected family members or unrelated controls. We reported a novel duplication in the PAX6 gene capable of causing the classic aniridia phenotype. This is the first report on the duplication in a North Indian family with autosomal dominant aniridia.

Abstract 3812: Induction of apoptosis by zeaxanthin in human uveal melanoma cells

INTRODUCTION Uveal melanoma is the highly malignant tumor of the eye and frequently leads to metastatic death. Depending on size and other parameters, traditional treatment of the primary tumor has been enucleation. However, alternative treatments to preserve the eye have been devised, including cryotherapy, radioactive therapy, transpupillary thermotherapy, surgical resection and photocoagulation. Despite these advances in treatment, mortality varies considerably, to more than 50% in high-risk patients, primarily due to metastasis to the liver. Therefore, it is critical to develop drugs that are non-toxic and can be administered for potentially extended periods to patients who have diagnosed with primary uveal melanoma. In recent years, Zeaxanthin, a naturally occurring carotenoid alcohol highly enriched in green leaves, has been used in medicine to treat various diseases. Epidemiological studies have shown that higher intake and higher blood levels of zeaxanthin appear to be associated with a lower risk of occurrence of various cancers. It has also been reported that zeaxanthin may inhibit cell growth or induce apoptosis of several tumor cell lines in vitro. The present study was designed to investigate the effect of zeaxanthin on human uveal melanoma cells. Methods Human uveal melanoma cells isolated from tissues of enucleated eyes were treated with zeaxanthin in a dose- and time-dependent manner. After zeaxanthin treatment, cell viability was measured using MTT assay. The proapoptotic and antiproliferative effects were evaluated by -annexin V staining and flow cytometry respectively. Mitochondrial transmembrane potential was measured as a function of drug treatment using 5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethyl-benzamidazolocarbocyanin iodide (JC-1). Immunoblotting was used to evaluate the expression of apoptosis-related proteins. Caspase-9 and -3 activities were determined by spectroflurometry. Results Zeaxanthin induced apoptosis in dose- and time-dependent manner. Decrease in the level of Bcl-2 and increase in the level of Bax were observed in zeaxanthin-treated in human uveal melanoma cells. Preceding cell death, zeaxanthin evoked a rapid dissipation of mitochondrial transmembrane potential. This was followed by the release of cytochrome c into the cytoplasm and a substantial increase in the activities of caspase-9 and -3. Conclusions These results demonstrate that zeaxanthin induces apoptosis through the regulation of Bcl-2 family protein and activation of intrinsic mitochondrial pathway. This may warrant further exploration as an adjuvant to conventional anticancer therapies for uveal melanoma. Citation Format: Sandeep Goswami, Arpna Srivastava, Neelam Pushker, Mandeep Singh Bajaj, Seema Kashyap, Jasbir Kaur. Induction of apoptosis by zeaxanthin in human uveal melanoma cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3812. doi:10.1158/1538-7445.AM2015-3812

Abstract P1-01-18: Sentinel lymph node identifcation in breast cancer using methylene blue and patent blue: A randomized controlled trial

Background: Sentinel lymph node biopsy (SLNB) is the standard of care for management of axilla in West. However, In India few centres have established SLN program for breast cancer. The main reason is non- availability & high cost of commercial blue dye & gamma probe. Methylene blue (MB) is not recommended for SLNB in West. The biochemical reason attributed for MB not being useful for SLNB has been its inability to bind to plasma proteins. However, Sutton has demonstrated the ability of MB in reducing the glutathione sulphhydryl group by nucleophilic additive mechanism that may explain the success of MB in identifying SLN I in few case series from third world .However, there is no RCT comparing SLN identification using MB and patent blue violet (PBV) till date. Aim:To compare the sentinel node (SN) identification rate using patent blue violet (PBV) in combination with radiotracer versus methylene blue (MB) in combination with radiotracer in breast cancer. Sample size: Assuming that MB identified SN in 75% of cases and PBV in 85% of cases, a two group continuity corrected X2 test with 0.05 two sided test will have 80% power to detect the difference when the sample size is 107. Materials and Methods: Clinically axillary lymph node negative (N0) patients with breast cancer with tumor (T) stage T1, T2; T3 and T4b were included in the study. T3 and T4b patients received NACT. Patients with palpable hard axillary lymph node, cytologically positive lymph node, stage IV diseae and thoses with previous history of surgery, radiation therapy to axila were excluded from the study. SLNB was performed using combination technique. TC99 sufur colloid was injected at periareolar site intradermally in all patients. Technique of blue dye injection was as follows- 4 ml of 1% PBV: 1 ml intradermal over the tumor, 0.5 ml at 12, 3, 6 and 9 o clock position intraparenchymal around the tumor and 1 ml subareolar. In the MB group, 4 ml of 1% MB was injected at same sites as above.The site of intradermal injection was included in the skin incision. The excised SLN were sent for frozen section and imprint cytology. If SLN was negative for metastasis, only SLNB was performed as surgical treatment of axilla. Results: Between Jan 2010- Jan 2013, 227 of 232 eligible patients (115 in MB arm & 112 in PBV arm) with primary breast cancer with clinically negative axilla consenting to take part in the study were enrolled. T status: T1: 48; T2:126; LABC: 37, Tx: 6. SLN was identified in 215/227 pts (95%). SLN was negative in 133 (62%). All SLN +ve patients (82; (38%) underwent ALND. Among those with positive SLN, SLN was the only positive node in 24 (29%) patients and rest had non sentinel nodes involvement (58; 71%). SLN identification rate using MB (107/112) in combination with Tc99 S Colloid was similar to that with PBV in combination with Tc99S colloid (108/115). Number of nodes harvested nodes (299 v/s 302), blue nodes (260v/s 261) and positive nodes (60 v/s 63) were similar in both groups. Conclusion: MB can be used for SLB in breast cancer with similar identification & false negative rates as PBV in institutions where commercial blue dye and facilities for radiotracer guided technique are not available. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-01-18.