Displaying publications 1 - 20 of 69 in total

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  1. Klionsky DJ, Abdelmohsen K, Abe A, Abedin MJ, Abeliovich H, Acevedo Arozena A, et al.
    Autophagy, 2016;12(1):1-222.
    PMID: 26799652 DOI: 10.1080/15548627.2015.1100356
  2. Singh S, Agarwal R, Razak ZA, Ngu R, Nyein LL, Vasudevan S, et al.
    J Ocul Pharmacol Ther, 2018 01 17;34(1-2):214-223.
    PMID: 29341837 DOI: 10.1089/jop.2017.0098
    PURPOSE: Pseudomonas aeruginosa is the most common causative organism for contact lens-associated corneal ulcer and is commonly treated with fluoroquinolones. With the emergence of resistant strains, it is important to investigate alternative therapies. Despite well-established efficacy of tazocin against systemic Pseudomonas infections, its topical use for the treatment of Pseudomonas keratitis has not been described, hence this study was aimed to find the ocular permeation of Tazocin and its efficacy in treating keratitis in rabbit eyes.

    METHODS: We investigated the ocular permeation of topical tazocin after single drop application in normal rabbit eyes by estimating piperacillin and tazobactam concentrations in cornea, aqueous, and vitreous using a validated LC-MS/MS method. Furthermore, we determined the efficacy of repeated dose administration of tazocin against experimentally induced P. aeruginosa keratitis in rabbits in comparison to moxifloxacin. To determine the efficacy, clinical examination, histopathological examination, and estimation of bacterial load and inflammatory cytokines in cornea were done.

    RESULTS: Significant corneal concentration of piperacillin and tazobactam was detected in normal rabbit corneas after single dose treatment with tazocin. In rabbits with Pseudomonas-induced keratitis, topical tazocin caused significant clinical and histopathological improvement. This improvement was associated with reduction in corneal bacterial load and inflammatory cytokines. Compared to moxifloxacin 0.5%, tazocin treated group showed greater clinical response which was associated with higher interleukin (IL)-1β, lower tumor necrosis factor (TNF)-α, a comparable level of IL-8, greater reduction in corneal bacterial load, and lesser inflammatory cell infiltration.

    CONCLUSION: Tazocin showed good ocular penetration and was effective in treatment of Pseudomonas induced keratitis in rabbits.

  3. Wong MG, Lv J, Hladunewich MA, Jha V, Hooi LS, Monaghan H, et al.
    Am J Nephrol, 2021;52(10-11):827-836.
    PMID: 34731857 DOI: 10.1159/000519812
    INTRODUCTION: Despite optimal current care, up to 30% of individuals suffering from immunoglobulin A nephropathy (IgAN) will develop kidney failure requiring dialysis or kidney transplantation. The Therapeutic Evaluation of STeroids in IgA Nephropathy Global (TESTING) study was designed to assess the benefits and risks of steroids in people with IgAN. We report the trial design as well as the baseline characteristics of study participants.

    METHODS: It is an investigator-initiated, multicenter, double-blind, placebo-controlled, randomized trial of individuals with kidney biopsy-confirmed IgAN, proteinuria ≥1 g/day, and an estimated GFR of 20-120 mL/min/1.73 m2, following at least 3 months of standard of care including maximum labelled (or tolerated) dose of renin-angiotensin system blockade. The original study design randomized participants 1:1 to oral methylprednisolone (0.6-0.8 mg/kg/day, maximum 48 mg/day) for 2 months, with subsequent weaning by 8 mg/day/month over 6-8 months, or matching placebo. The intervention was modified in 2016 (due to an excess of serious infection) to low-dose methylprednisolone (0.4 mg/kg/day, maximum 32 mg/day) for 2 months, followed by weaning by 4 mg/day/month over 6-9 months, or matching placebo. Participants recruited after 2016 also received prophylaxis against Pneumocystis jirovecii pneumonia during the first 12 weeks of treatment.

    RESULTS: The study recruitment period extended from May 2012 to November 2019. By the time the excess of serious infections was observed, 262 participants had been randomized to the original full-dose treatment algorithm, and an interim analysis was reported in 2016. Subsequently, 241 additional participants were randomized to a revised low-dose protocol, for a total of 503 participants from China (373), India (78), Canada (24), Australia (18), and Malaysia (10). The mean age of randomized participants was 38, 39% were female, mean eGFR at randomization was 62.7 mL/min/1.73 m2, and mean 24-h urine protein 2.54 g. The primary endpoint is a composite of 40% eGFR decline from baseline or kidney failure (dialysis, transplantation, or death due to kidney disease), and participants will be followed until the primary outcome has been observed in at least 160 randomized participants. Analyses will also be made across predefined subgroups. Effects on eGFR slope and albuminuria will also be assessed overall, as well as by the steroid dosing regimen.

    CONCLUSIONS: The TESTING study (combined full and low dose) will define the benefits of corticosteroid use on major kidney outcomes, as well as the risks of therapy, and provide data on the relative effects of different doses, in individuals with high-risk IgAN.

  4. Lv J, Wong MG, Hladunewich MA, Jha V, Hooi LS, Monaghan H, et al.
    JAMA, 2022 May 17;327(19):1888-1898.
    PMID: 35579642 DOI: 10.1001/jama.2022.5368
    IMPORTANCE: The effect of glucocorticoids on major kidney outcomes and adverse events in IgA nephropathy has been uncertain.

    OBJECTIVE: To evaluate the efficacy and adverse effects of methylprednisolone in patients with IgA nephropathy at high risk of kidney function decline.

    DESIGN, SETTING, AND PARTICIPANTS: An international, multicenter, double-blind, randomized clinical trial that enrolled 503 participants with IgA nephropathy, proteinuria greater than or equal to 1 g per day, and estimated glomerular filtration rate (eGFR) of 20 to 120 mL/min/1.73 m2 after at least 3 months of optimized background care from 67 centers in Australia, Canada, China, India, and Malaysia between May 2012 and November 2019, with follow-up until June 2021.

    INTERVENTIONS: Participants were randomized in a 1:1 ratio to receive oral methylprednisolone (initially 0.6-0.8 mg/kg/d, maximum 48 mg/d, weaning by 8 mg/d/mo; n = 136) or placebo (n = 126). After 262 participants were randomized, an excess of serious infections was identified, leading to dose reduction (0.4 mg/kg/d, maximum 32 mg/d, weaning by 4 mg/d/mo) and addition of antibiotic prophylaxis for pneumocystis pneumonia for subsequent participants (121 in the oral methylprednisolone group and 120 in the placebo group).

    MAIN OUTCOMES AND MEASURES: The primary end point was a composite of 40% decline in eGFR, kidney failure (dialysis, transplant), or death due to kidney disease. There were 11 secondary outcomes, including kidney failure.

    RESULTS: Among 503 randomized patients (mean age, 38 years; 198 [39%] women; mean eGFR, 61.5 mL/min/1.73 m2; mean proteinuria, 2.46 g/d), 493 (98%) completed the trial. Over a mean of 4.2 years of follow-up, the primary outcome occurred in 74 participants (28.8%) in the methylprednisolone group compared with 106 (43.1%) in the placebo group (hazard ratio [HR], 0.53 [95% CI, 0.39-0.72]; P 

  5. Agarwal R, Iezhitsa IN, Agarwal P, Spasov AA
    Magnes Res, 2013 Jan-Feb;26(1):2-8.
    PMID: 23708888 DOI: 10.1684/mrh.2013.0336
    Senile cataract is the most common cause of bilateral blindness and results from the loss of transparency of the lens. Maintenance of the unique tissue architecture of the lens is vital for keeping the lens transparent. Membrane transport mechanisms utilizing several magnesium (Mg)-dependent ATPases, play an important role in maintaining lens homeostasis. Therefore, in Mg-deficiency states, ATPase dysfunctions lead to intracellular depletion of K(+) and accumulation of Na(+) and Ca(2+). High intracellular Ca(2+) causes activation of the enzyme calpain II, which leads to the denaturation of crystallin, the soluble lens protein required for maintaining the transparency of the lens. Mg deficiency also interferes with ATPase functions by causing cellular ATP depletion. Furthermore, Mg deficiency enhances lenticular oxidative stress by increased production of free radicals and depletion of antioxidant defenses. Therefore, Mg supplementation may be of therapeutic value in preventing the onset and progression of cataracts in conditions associated with Mg deficiency.
  6. Agarwal R, Iezhitsa I, Agarwal P, Spasov A
    Exp Eye Res, 2012 Aug;101:82-9.
    PMID: 22668657 DOI: 10.1016/j.exer.2012.05.008
    Magnesium is one of the most important regulatory cation involved in several biological processes. It is important for maintaining the structural and functional integrity of vital ocular tissues such as lens. Presence of high magnesium content especially in the peripheral part of lens as compared to aqueous and vitreous humor has been observed. Magnesium plays significant role as a cofactor for more than 350 enzymes in the body especially those utilizing ATP. Membrane associated ATPase functions that are crucial in regulating the intracellular ionic environment, are magnesium-dependent. Moreover, the enzymes involved in ATP production and hydrolysis are also magnesium-dependent. Magnesium deficiency by interfering with ATPase functions causes increased intracellular calcium and sodium and decreases intracellular potassium concentration. Furthermore, magnesium deficiency is associated with increased oxidative stress secondary to increased expression of inducible nitric oxide synthase and increased production of nitric oxide. Thus the alterations in lenticular redox status and ionic imbalances form the basis of the association of magnesium deficiency with cataract. In this paper we review the mechanisms involved in magnesium homeostasis and the role of magnesium deficiency in the pathogenesis of cataract.
  7. Azis NA, Agarwal R, Ismail NM, Ismail NH, Kamal MSA, Radjeni Z, et al.
    Mol Biol Rep, 2019 Jun;46(3):2841-2849.
    PMID: 30977084 DOI: 10.1007/s11033-019-04730-w
    This study investigated the effects of a standardised ethanol and water extract of Ficus deltoidea var. Kunstleri (FDK) on blood pressure, renin-angiotensin-aldosterone system (RAAS), endothelial function and antioxidant system in spontaneously hypertensive rats (SHR). Seven groups of male SHR were administered orally in volumes of 0.5 mL of either FDK at doses of 500, 800, 1000 and 1300 mg kg- 1, or captopril at 50 mg kg- 1 or losartan at 10 mg kg- 1 body weight once daily for 4 weeks or 0.5 mL distilled water. Body weight, systolic blood pressures (SBP) and heart rate (HR) were measured every week. 24-hour urine samples were collected at weeks 0 and 4 for electrolyte analysis. At week 4, sera from rats in the control and 1000 mg kg- 1 of FDK treated groups were analyzed for electrolytes and components of RAAS, endothelial function and anti-oxidant capacity. SBP at week 4 was significantly lower in all treatment groups, including captopril and losartan, when compared to that of the controls. Compared to the controls, ACE activity and concentrations of angiotensin I, angiotensin II and aldosterone were lower whereas concentrations of angiotensinogen and angiotensin converting enzyme 2 were higher in FDK treated rats. Concentration of eNOS and total anti-oxidant capacity were higher in FDK treated rats. Urine calcium excretion was higher in FDK treated rats. In conclusion, it appears that ethanol and water extract of FDK decreases blood pressure in SHR, which might involve mechanisms that include RAAS, anti-oxidant and endothelial system.
  8. Ramesh V, Singh S, Bailwad S, Kiran K, Agarwal R, Singh A
    Ann Med Health Sci Res, 2014 Mar;4(Suppl 1):S14-7.
    PMID: 25031898 DOI: 10.4103/2141-9248.131694
    Ameloblastoma is usually considered a homogenous neoplasm and is thought of as the most primitive of all odontogenic neoplasms. However, detailed investigations have proven clinicopathological diversity in a significant number of cases, thus mounting the evidence in favor of considering ameloblastoma as a mysterious lesion. The purpose of this article is to report a unique case of desmoplastic ameloblastoma and to throw light on the atypical changes noticed in the stromal component. The findings of this case have served to add interesting parameters to the study of stromal changes associated with this perplexing odontogenic tumor.
  9. Abd Ghapor AA, Abdul Nasir NA, Iezhitsa I, Agarwal R, Razali N
    Neurosci Res, 2023 Aug;193:1-12.
    PMID: 36796452 DOI: 10.1016/j.neures.2023.02.004
    Adenosine A1 receptors (AA1R) have been shown to counteract N-methyl-D-aspartate (NMDA)-mediated glutamatergic excitotoxicity. In the present study, we investigated the role of AA1R in neuroprotection by trans-resveratrol (TR) against NMDA-induced retinal injury. In total, 48 rats were divided into the following four groups: normal rats pretreated with vehicle; rats that received NMDA (NMDA group); rats that received NMDA after pretreatment with TR; and rats that received NMDA after pretreatment with TR and 1,3-dipropyl-8-cyclopentylxanthine (DPCPX), an AA1R antagonist. Assessment of general and visual behaviour was performed using the open field test and two-chamber mirror test, respectively, on Days 5 and 6 post NMDA injection. Seven days after NMDA injection, animals were euthanized, and eyeballs and optic nerves were harvested for histological parameters, whereas retinae were isolated to determine the redox status and expression of pro- and anti-apoptotic proteins. In the present study, the retinal and optic nerve morphology in the TR group was protected from NMDA-induced excitotoxic damage. These effects were correlated with the lower retinal expression of proapoptotic markers, lipid peroxidation, and markers of nitrosative/oxidative stress. The general and visual behavioural parameters in the TR group showed less anxiety-related behaviour and better visual function than those in the NMDA group. All the findings observed in the TR group were abolished by administration of DPCPX.
  10. Abdul Ghani NA, Abdul Nasir NA, Lambuk L, Sadikan MZ, Agarwal R, Ramli N
    Graefes Arch Clin Exp Ophthalmol, 2023 Jun;261(6):1587-1596.
    PMID: 36622408 DOI: 10.1007/s00417-022-05965-3
    PURPOSE: Angiogenesis in diabetic retinopathy (DR) is associated with increased retinal expression of angiopoietin-2 (Ang-2) and protein kinase C (PKC). Tocotrienol-rich fraction (TRF) has been shown to reduce the expression vascular endothelial growth factor (VEGF) in several experimental models. However, its effect against other angiogenic markers such as Ang-2 and PKC in rat model of diabetes remains unknown. Therefore, we investigated the effect of TRF on the retinal vascular changes and Ang-2 and PKC expressions in rats with streptozotocin (STZ)-induced DR.

    METHODS: Sprague-Dawley rats were divided into normal control rats (N) which received vehicle, and diabetic rats which either received vehicle (DV) or 100 mg/kg of TRF (DT). Diabetes was induced with intraperitoneal injection of STZ (60 mg/kg body weight). Treatments were given orally, once daily, for 12 weeks after confirmation of hyperglycaemia. Fundus photographs were captured at baseline, 6- and 12-week post-STZ injection and average diameter of retinal veins and arteries were measured. At 12-week post-STZ injection, rats were euthanised, and retinae were collected for measurement of Ang-2 and PKC gene and protein expressions.

    RESULTS: Retinal venous and arterial diameters were significantly greater in DV compared to DT at week 12 post-STZ injection (p 

  11. Abdullah F, Khan Nor-Ashikin MN, Agarwal R, Kamsani YS, Abd Malek M, Bakar NS, et al.
    Asian J Androl, 2021 1 22;23(3):281-287.
    PMID: 33473013 DOI: 10.4103/aja.aja_81_20
    Diabetes mellitus (DM) is known to cause reproductive impairment. In men, it has been linked to altered sperm quality and testicular damage. Oxidative stress (OS) plays a pivotal role in the development of DM complications. Glutathione (GSH) is a part of a nonenzymatic antioxidant defense system that protects lipid, protein, and nucleic acids from oxidative damage. However, the protective effects of exogenous GSH on the male reproductive system have not been comprehensively examined. This study determined the impact of GSH supplementation in ameliorating the adverse effect of type 1 DM on sperm quality and the seminiferous tubules of diabetic C57BL/6NTac mice. GSH at the doses of 15 mg kg-1 and 30 mg kg-1 was given intraperitoneally to mice weekly for 6 consecutive weeks. The mice were then weighed, euthanized, and had their reproductive organs excised. The diabetic (D Group) showed significant impairment of sperm quality and testicular histology compared with the nondiabetic (ND Group). Diameters of the seminiferous lumen in diabetic mice treated with 15 mg kg-1 GSH (DGSH15) were decreased compared with the D Group. Sperm motility was also significantly increased in the DGSH15 Group. Improvement in testicular morphology might be an early indication of the protective roles played by the exogenous GSH in protecting sperm quality from effects of untreated type 1 DM or diabetic complications. Further investigation using different doses and different routes of GSH is necessary to confirm this suggestion.
  12. Agarwal R, Krasilnikova AV, Raja IS, Agarwal P, Mohd Ismail N
    Eur J Pharmacol, 2014 May 5;730:8-13.
    PMID: 24583339 DOI: 10.1016/j.ejphar.2014.02.021
    Angiotensin converting enzyme inhibitors (ACEIs) have been shown to lower intraocular pressure (IOP). Since, the ACEIs cause increased tissue prostaglandin levels, we hypothesized that the mechanisms of ACEI-induced IOP reduction have similarity with those of prostaglandin analogs. The present study investigated the involvement of matrix metalloproteinases (MMPs) and cytokine activity modulation as the underlying mechanisms of ACEI-induced ocular hypotension. The IOP lowering effect of single drop of enalaprilat dehydrate 1% was evaluated in rats pretreated with a broad spectrum MMP inhibitor or a cytokine inhibitor. Effect of angiotensin receptor blocker, losartan potassium 2%, was also studied to evaluate involvement of angiotensin II receptor type 1 (AT1) in IOP lowering effect of ACEI. Topical treatment with single drop of enalaprilat resulted in significant IOP reduction in treated eye with mean peak reduction 20.3% at 3h post-instillation. Treatment with losartan resulted in a peak IOP reduction of 13.3%, which was significantly lower than enalaprilat, indicating involvement of mechanisms in addition to AT1 blockade. Pretreatment with a broad spectrum MMP inhibitor or a cytokine inhibitor significantly attenuated the enalprilat-induced IOP reduction with mean peak IOP reduction of 11.2% and 13.6% respectively. The IOP-lowering effect of enalaprilat seems to be attributed to reduced angiotensin II type 1 receptor stimulation and modulation of MMP and cytokines activities.
  13. Agarwal R, Iezhitsa I, Awaludin NA, Ahmad Fisol NF, Bakar NS, Agarwal P, et al.
    Exp Eye Res, 2013 May;110:35-43.
    PMID: 23428743 DOI: 10.1016/j.exer.2013.02.011
    Cataract, a leading cause of blindness, is characterized by lenticular opacities resulting from denaturation of lens proteins due to activation of calcium-dependent enzyme, calpain. Magnesium (Mg(2+)) plays an important role not only in maintaining a low lenticular calcium (Ca(2+)) and sodium concentration but also in preserving the lens redox status. Taurine has also been shown to reduce lenticular oxidative stress. Present study evaluated the anticataract effects of magnesium taurate in vivo and in vitro. Among the five groups of 9 Sprague Dawley rats each, two groups received 30% galactose diet with topical (GDMT) or oral treatment (GDMO) with magnesium taurate. Two groups received 30% galactose diet with topical (GDT) or oral vehicle (GDO). Remaining 1 group received normal diet (ND). Weekly slit lamp examination was done during 21 days experimental period and then all rats were sacrificed; Ca/Mg ratio and antioxidant parameters including reduced glutathione (GSH), catalase and superoxide dismutase (SOD) activities were measured in the isolated lenses using ELISA. In the in vitro study, 2 groups of 10 normal rat lenses were incubated in Dulbecco's Modified Eagle's Medium (DMEM) with galactose while 1 similar group was incubated in DMEM without galactose. In one of the groups, galactose containing medium was supplemented with magnesium taurate. After 48 h of incubation, lenses were photographed and Ca(2+)/Mg(2+) ratio and antioxidant parameters were measured as for in vivo study. The in vivo study, at the end of experimental period, demonstrated delay in the development of cataract with a mean opacity index of 0.53 ± 0.04 and 0.51 ± 0.03 in GDMO (p < 0.05 versus GDO) and GDMT (p < 0.01 versus GDT) respectively. Histopathological grading showed a lower mean value in treated groups, however, the differences from corresponding controls were not significant. Lenticular Ca(2+)/Mg(2+) ratio with a mean value of 1.20 ± 0.26 and 1.05 ± 0.26 in GDMO and GDMT was significantly lower than corresponding controls (p < 0.05) and in GDMT no significant difference was observed from ND. Lenticular GSH and catalase activities were significantly lower and SOD activity was significantly higher in all galactose fed groups. However, in GDMT, GSH and catalase were significantly higher than corresponding control with mean values of 0.96 ± 0.30 μmol/gm lens weight and 56.98 ± 9.86 μmol/g lens protein respectively (p < 0.05 for GSH and p < 0.01 for catalase). SOD activity with mean values of 13.05 ± 6.35 and 13.27 ± 7.61 units/mg lens protein in GDMO and GDMT respectively was significantly lower compared to corresponding controls (p < 0.05) signifying lesser upregulation of SOD due to lesser oxidative stress in treated groups. In the in vitro study, lenses incubated in magnesium taurate containing medium showed less opacity and a lower mean Ca(2+)/Mg(2+) ratio of 1.64 ± 0.03, which was not significantly different from lenses incubated in DMEM without galactose. Lens GSH and catalase activities were restored to normal in lenses incubated in magnesium taurate containing medium. Both in vivo and in vitro studies demonstrated that treatment with magnesium taurate delays the onset and progression of cataract in galactose fed rats by restoring the lens Ca(2+)/Mg(2+) ratio and lens redox status.
  14. Arfuzir NN, Lambuk L, Jafri AJ, Agarwal R, Iezhitsa I, Sidek S, et al.
    Neuroscience, 2016 06 14;325:153-64.
    PMID: 27012609 DOI: 10.1016/j.neuroscience.2016.03.041
    Vascular dysregulation has long been recognized as an important pathophysiological factor underlying the development of glaucomatous neuropathy. Endothelin-1 (ET1) has been shown to be a key player due to its potent vasoconstrictive properties that result in retinal ischemia and oxidative stress leading to retinal ganglion cell (RGC) apoptosis and optic nerve (ON) damage. In this study we investigated the protective effects of magnesium acetyltaurate (MgAT) against retinal cell apoptosis and ON damage. MgAT was administered intravitreally prior to, along with or after administration of ET1. Seven days post-injection, animals were euthanized and retinae were subjected to morphometric analysis, TUNEL and caspase-3 staining. ON sections were stained with toluidine blue and were graded for neurodegenerative effects. Oxidative stress was also estimated in isolated retinae. Pre-treatment with MgAT significantly lowered ET1-induced retinal cell apoptosis as measured by retinal morphometry and TUNEL staining. This group of animals also showed significantly lesser caspase-3 activation and significantly reduced retinal oxidative stress compared to the animals that received intravitreal injection of only ET1. Additionally, the axonal degeneration in ON was markedly reduced in MgAT pretreated animals. The animals that received MgAT co- or post-treatment with ET1 also showed improvement in all parameters; however, the effects were not as significant as observed in MgAT pretreated animals. The current study showed that the intravitreal pre-treatment with MgAT reduces caspase-3 activation and prevents retinal cell apoptosis and axon loss in ON induced by ET1. This protective effect of ET1 was associated with reduced retinal oxidative stress.
  15. Abdul Nasir NA, Agarwal P, Agarwal R, Iezhitsa I, Alyautdin R, Nukolova NN, et al.
    Drug Deliv, 2016 Oct;23(8):2765-71.
    PMID: 26289215
    Topical administration is the preferred route of drug delivery for ophthalmic ailments. However, poor permeation through ocular surface and significant systemic absorption, makes the topical drug delivery challenging. Furthermore, distribution of topically delivered drugs varies with their physicochemical properties and the type of formulation used. Hence, this study was done to understand the pattern of ocular drug distribution of topically applied hydrophilic and lipophilic substances in two different formulations.
  16. Agarwal R, Mohd Ismail N
    Introduction: The study attempts to evaluate the students’ perception of pharmacology as a
    subject, its usefulness in future practice, teaching methods currently used, and their patterns of
    learning and preparing for exams. Methods: A structured, self-administered questionnaire was
    distributed to second year medical students. Results: Of the 125 students who participated,
    22.73 % considered pharmacology more important than any other subject. The students found
    small group sessions most interesting followed by directed self-learning, computer aided
    learning and lectures. Of those who responded, 79 and 66 % suggested to increase the small
    group and directed-self-learning sessions respectively. Up to 40 % of the students felt that
    pharmacology teaching must be through case-based discussions and 20 % requested for more
    practical sessions. Conclusions: It appears that majority of students entering the medical
    schools has little prior knowledge of pharmacology. While going through the preclinical years
    they understood the importance of pharmacology and its application in future practice,
    however, they tend to develop interest in one or other topics. Students prefer to have a greater
    number of small group sessions as they feel that these sessions are most useful for learning.
    Majority of the students tend to use both the textbooks and lecture notes and study regularly
    for better performance in examinations. The students also preferred to have more case-based
    learning sessions incorporated into the small group sessions.
    KEYWORDS: Pharmacology teaching, student perception, teaching methodologies
  17. Mohd Lazaldin MA, Iezhitsa I, Agarwal R, Bakar NS, Agarwal P, Mohd Ismail N
    Eur J Neurosci, 2020 06;51(12):2394-2411.
    PMID: 31883161 DOI: 10.1111/ejn.14662
    Brain-derived neurotrophic factor (BDNF) could be considered a potential neuroprotective therapy in amyloid beta (Aβ)-associated retinal and optic nerve degeneration. Hence, in this study we investigated the neuroprotective effect of BDNF against Aβ1-40-induced retinal and optic nerve injury. In this study, exposure to Aβ1-40 was associated with retinal and optic nerve injury. TUNEL staining showed significant reduction in the apoptotic cell count in the BDNF-treated group compared with Aβ1-40 group. H&E-stained retinal sections also showed a striking reduction in neuronal cells in the ganglion cell layer (GCL) of retinas fourteen days after Aβ1-40 exposure. By contrast, number of retinal cells was preserved in the retinas of BDNF-treated animals. After Aβ1-40 exposure, visible axonal swelling was observed in optic nerve sections. However, the BDNF-treated group showed fewer changes in optic nerve; axonal swelling was less frequent and less marked. In the present study, exposure to Aβ was associated with oxidative stress, whereas levels of retinal glutathione (GSH), superoxide dismutase (SOD) and catalase were significantly increased in BDNF-treated than in Aβ1-40-treated rats. Both visual object recognition tests using an open-field arena and a Morris water maze showed that BDNF improved rats' ability to recognise visual cues (objects with different shapes) after Aβ1-40 exposure, thus demonstrating that the visual performance of rats was relatively preserved following BDNF treatment. In conclusion, intravitreal treatment with BDNF prevents Aβ1-40-induced retinal cell apoptosis and axon loss in the optic nerve of rats by reducing retinal oxidative stress and restoring retinal BDNF levels.
  18. Marcus AJ, Iezhitsa I, Agarwal R, Vassiliev P, Spasov A, Zhukovskaya O, et al.
    Data Brief, 2018 Jun;18:523-554.
    PMID: 29896529 DOI: 10.1016/j.dib.2018.03.019
    This data is to document the intraocular pressure (IOP) lowering activity of imidazo[1,2-a]benzimidazole and pyrimido[1,2-a]benzimidazole compounds in ocular normotensive rats. Effects of single drop application of imidazo[1,2-a]benzimidazole and pyrimido[1,2-a]benzimidazole compounds on IOP in ocular normotensive rats are presented at 3 different concentrations (0.1%, 0.2% and 0.4%). Time course of changes in IOP is presented over 6 h period post-instillation. The IOP lowering activities of test compounds were determined by assessing maximum decrease in IOP from baseline and corresponding control, duration of IOP lowering and area under curve (AUC) of time versus response curve. Data shown here may serve as benchmarks for other researchers studying IOP-lowering effect of imidazo[1,2-a]benzimidazole and pyrimido[1,2-a]benzimidazole compounds and would be useful in determining therapeutic potential of these test compounds as IOP lowering agents.
  19. Abdul Nasir NA, Agarwal R, Sheikh Abdul Kadir SH, Vasudevan S, Tripathy M, Iezhitsa I, et al.
    PLoS One, 2017;12(3):e0174542.
    PMID: 28350848 DOI: 10.1371/journal.pone.0174542
    Cataract, a leading cause of blindness, is of special concern in diabetics as it occurs at earlier onset. Polyol accumulation and increased oxidative-nitrosative stress in cataractogenesis are associated with NFκB activation, iNOS expression, ATP depletion, loss of ATPase functions, calpain activation and proteolysis of soluble to insoluble proteins. Tocotrienol was previously shown to reduce lens oxidative stress and inhibit cataractogenesis in galactose-fed rats. In current study, we investigated anticataract effects of topical tocotrienol and possible mechanisms involved in streptozotocin-induced diabetic rats. Diabetes was induced in Sprague Dawley rats by intraperitoneal injection of streptozotocin. Diabetic rats were treated with vehicle (DV) or tocotrienol (DT). A third group consists of normal, non-diabetic rats were treated with vehicle (NV). All treatments were given topically, bilaterally, twice daily for 8 weeks with weekly slit lamp monitoring. Subsequently, rats were euthanized and lenses were subjected to estimation of polyol accumulation, oxidative-nitrosative stress, NFκB activation, iNOS expression, ATP levels, ATPase activities, calpain activity and total protein levels. Cataract progression was delayed from the fifth week onwards in DT with lower mean of cataract stages compared to DV group (p<0.01) despite persistent hyperglycemia. Reduced cataractogenesis in DT group was accompanied with lower aldose reductase activity and sorbitol level compared to DV group (p<0.01). DT group also showed reduced NFκB activation, lower iNOS expression and reduced oxidative-nitrosative stress compared to DV group. Lenticular ATP and ATPase and calpain 2 activities in DT group were restored to normal. Consequently, soluble to insoluble protein ratio in DT group was higher compared to DV (p<0.05). In conclusion, preventive effect of topical tocotrienol on development of cataract in STZ-induced diabetic rats could be attributed to reduced lens aldose reductase activity, polyol levels and oxidative-nitrosative stress. These effects of tocotrienol invlove reduced NFκB activation, lower iNOS expression, restoration of ATP level, ATPase activities, calpain activity and lens protein levels.
  20. Nor Arfuzir NN, Agarwal R, Iezhitsa I, Agarwal P, Sidek S, Spasov A, et al.
    Curr Eye Res, 2018 08;43(8):1032-1040.
    PMID: 29676937 DOI: 10.1080/02713683.2018.1467933
    PURPOSE: Retinal ganglion cell apoptosis in glaucoma is associated with elevated levels of endothelin-1 (ET1), a potent vasoconstrictor. ET1-induced retinal ischemia leads to altered expression of nitric oxide synthase (NOS) isoforms leading to increased formation of nitric oxide (NO) and retinal nitrosative stress. Since magnesium (Mg) is known to improve endothelial functions and reduce oxidative stress and taurine (TAU) possesses potent antioxidant properties, we investigated the protective effects of magnesium acetyltaurate (MgAT) against ET1-induced nitrosative stress and retinal damage in rats. We also compared the effects of MgAT with that of TAU alone.

    METHODS: Sprague Dawley rats were intravitreally injected with ET1. MgAT and TAU were administered as pre-, co-, or posttreatment. Subsequently, the expression of NOS isoforms was detected in retina by immunohistochemistry, retinal nitrotyrosine level was estimated using ELISA, and retinal cell apoptosis was detected by TUNEL staining.

    RESULTS: Intravitreal ET1 caused a significant increase in the expressions of nNOS and iNOS while eNOS expression was significantly reduced compared to vehicle treated group. Administration of both MgAT and TAU restored the altered levels of NOS isoform expression, reduced retinal nitrosative stress and retinal cell apoptosis. The effect of MgAT, however, was greater than that of TAU alone.

    CONCLUSIONS: MgAT and TAU prevent ET1-induced retinal cell apoptosis by reducing retinal nitrosative stress in Sprague Dawley rats. Addition of TAU to Mg seems to enhance the efficacy of TAU compared to when given alone. Moreover, the pretreatment with MgAT/TAU showed higher efficacy compared to co- or posttreatment.

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