Fisetin, an inhibitor of cyclin-dependent kinase 6, down-regulates nuclear factor-kappaB-regulated cell proliferation, antiapoptotic and metastatic gene products through the suppression of TAK-1 and receptor-interacting protein-regulated IkappaBalpha kinase activation

Fisetin (3,7,3',4'-tetrahydroxyflavone) exhibits anti-inflammatory and antiproliferative effects through a mechanism that is poorly understood. Although fisetin has been cocrystalized with cyclin-dependent kinase 6 and inhibits its activity, this inhibition is not sufficient to explain various activities assigned to this flavonol. Because of the critical role of the NF-kappaB pathway in regulation of inflammation and proliferation of tumor cells, we postulated that fisetin modulates this pathway. To test this hypothesis, we examined the effect of fisetin on NF-kappaB and NF-kappaB-regulated gene products in vitro. We found that among nine different flavones tested, fisetin was potent in suppressing tumor necrosis factor (TNF)-induced NF-kappaB activation. Fisetin also suppressed the NF-kappaB activation induced by various inflammatory agents and carcinogens, and it blocked the phosphorylation and degradation of IkappaBalpha by inhibiting IkappaBalpha (IKK) activation, which in turn led to suppression of the phosphorylation and nuclear translocation of p65. NF-kappaB-dependent reporter gene expression was also suppressed by fisetin, as was NF-kappaB reporter activity induced by TNFR1, TRADD, TRAF2, NIK, and IKK but not that induced by p65 transfection. Fisetin also inhibited TNF-induced TAK1 and receptor-interacting protein activation, events that lie upstream of IKK activation. The expression of NF-kappaB-regulated gene products involved in antiapoptosis (cIAP-1/2, Bcl-2, Bcl-xL, XIAP, Survivin, and TRAF1), proliferation (cyclin D1, c-Myc, COX-2), invasion (ICAM-1 and MMP-9), and angiogenesis (vascular endothelial growth factor) were also down-regulated by fisetin. This correlated with potentiation of apoptosis induced by TNF, doxorubicin, and cisplatin. Thus, overall, our results indicate that fisetin mediates antitumor and anti-inflammatory effects through modulation of NF-kappaB pathways.     

Outcome of cytomegalovirus retinitis in immunocompromised patients without Human Immunodeficiency Virus treated with intravitreal ganciclovir injection

Purpose

To study the outcomes of treatment with intravitreal ganciclovir injection for cytomegalovirus (CMV) retinitis in patients without Human Immunodeficiency Virus (HIV) infection.

Methods

In this retrospective cohort study, demographic and clinical characteristics of patients with CMV retinitis without HIV were noted. Patients received intravitreal ganciclovir injection (2 mg/0.1 ml) alone until quiescence. The outcome measures were time taken for the lesions to heal, number of injections, change in best-corrected visual acuity (BCVA), recurrence of retinitis, occurrence of immune recovery uveitis (IRU) or injection-related complications and retinal detachment (RD).

Results

18 eyes of ten patients (six males) with mean age of 33.7 years from June 2004 to March 2013 were included. Thirteen eyes with active lesions (mean BCVA of 0.51?±?0.41) received 5.54?±?3.36 intravitreal ganciclovir injections with complete healing within 1.81?±?1.25 months. The final BCVA was 0.43?±?0.52. IRU was observed in six eyes (33.33 %) and RD developed in one eye. One eye had recurrence 1 month after stopping ganciclovir injections. The rest of the patients had recurrence-free follow-up at 9.46?±?12.42 months.

Conclusions

Non-HIV patients with CMV retinitis can be successfully treated with intravitreal ganciclovir injection alone, avoiding the systemic side effects of systemic anti-CMV therapy.     

Induction of Th1-type cellular responses in cured/exposed Leishmania-infected patients and hamsters against polyproteins of soluble Leishmania donovani promastigotes ranging from 89.9 to 97.1 kDa

Earlier, we have identified soluble antigenic fraction ranging from 68 to 97.4kDa (F2-fraction) of Leishmania donovani promastigote, which induced Th1-immunostimulatory cellular responses in both cured Leishmania patients/hamsters and exhibited significant prophylactic potential against experimental visceral leishmaniasis (VL). In the present study, we have further fractionated F2-fraction by continuous elution SDS-PAGE and subjected them to re-evaluation for their ability to induce cellular responses. Out of seven sub-fractions: F2.1-F2.7, only four F2.4-F2.7 (89.9-97.1kDa), individually or in pooled sub-fractions (P4-7), stimulated Th1-type remarkable lymphoproliferative, NO, IFN-gamma and IL-12 responses in Leishmania-infected cured/exposed patients and hamsters. Interestingly, optimum Th1-responses were obtained with P4-7 suggesting the presence of immunostimulatory molecules in it and may be exploited for developing a successful subunit vaccine against VL.     

Increased hyperalgesia by 5-nitro-2, 3-(phenylpropylamino)-benzoic acid (NPPB), a chloride channel blocker in crush injury-induced neuropathic pain in rats

Chloride channels belong to diverse group of anion selective channels involved in different signaling processes. The present study was planned to investigate the involvement of chloride channels in crush injury-induced neuropathic pain in rats by using ivermectin, a ligand gated chloride channel opener and NPPB, a CaCC blocker. The effect of ivermectin (5, 10, 20 mg/kg i.p. or 50, 100 and 200 μg/rat by i.c.v. route) and NPPB (10, 20 and 40 mg/kg i.p.) was investigated on pain behavioural thresholds in crush injury-induced neuropathic pain rat model. Reduction in pain threshold by mechanical, thermal and cold stimuli confirmed the development of neuropathic pain in rats after crush injury. Ivermectin administered either by i.p. or i.c.v. route did not alter the pain threshold in mechanical, thermal and, cold allodynia tests in rats. NPPB (20 and 40 mg/kg i.p.) significantly reduced the pain threshold crush injury neuropathic pain model suggesting its hyperalgesic effect. The results showed that NPPB increased significantly the mechanical and thermal hyperalgesia in crush injury-induced neuropathic pain rat model, whereas ivermectin, either by i.p. or i.c.v. route of administration, has no effect on pain symptoms in this model. NPPB hyperalgesic effect is independent of CaCCs inhibition and may be due to blockade of Ca²⁺-activated K⁺ channel.     

Safety evaluation of Monascus purpureus red mould rice in albino rats

Monascus purpureus MTCC 410-fermented rice (red mould rice) is one of the food supplements to lower blood–lipid levels and monacolins have been proven to be the main active constituents in red mould rice (RMR). In this study, we have assessed the safety of RMR by conducting toxicological studies in albino rats. Acute and sub-chronic toxicity studies were conducted on both sexes of albino rats. Feeding acute doses of RMR at 0.5, 1.0, 2.5 and 5.0 g/kg body weight to rats did not cause any symptoms of toxicity or mortality. Similarly, dietary feeding of RMR at 2.0%, 4.0%, 8.0% and 12.0% level (w/w) for 14 weeks did not produce any significant changes in food intake or gain in body weight of the experimental rats compared to control rats. There were no significant differences in the relative weight of vital organs, hematological parameters, macroscopic and microscopic changes in vital organs and serum clinical enzyme levels between the experimental and control groups. Moreover, the rats fed with RMR showed a significant reduction in cholesterol and triglyceride levels in both serum and liver. The results showed that toxicity studies with RMR of M. purpureus did not cause any toxic effects in albino rats.     

Differential role of sodium channels SCN1A and SCN2A gene polymorphisms with epilepsy and multiple drug resistance in the north Indian population

AIMS

To evaluate sodium channel genes as candidates for epilepsy susceptibility and their role in therapeutic efficacy, we screened coding single-nucleotide polymorphism of SCN1A p. Thr 1067 Ala or c.3184 A→G (rs2298771) and SCN2A p.Arg19Lys or c.56 G→A (rs17183814) in north Indian epilepsy patients.

METHODS

The genotyping was performed in 160 control subjects and 336 patients with epilepsy, of whom 117 were drug resistant and 219 were drug responsive. Therapeutic drug monitoring for phenytoin, carbamazepine, phenobarbital and valproate was also performed in 20% of the patients to confirm compliance.

RESULTS

AG genotype of SCN1A 3184 A→G polymorphism was significantly higher and associated in epilepsy patients [P= 0.005; odds ratio (OR) 1.76, 95% confidence interval (CI) 1.19, 2.61], whereas A variant of SCN2A c.56 G→A was associated with multiple drug resistance in north Indian patients with epilepsy (P= 0.03; OR 1.62, 95% CI 1.03, 2.56).

CONCLUSIONS

Overall, results indicate a differential role of genetic polymorphisms of sodium channels SCN1A and SCN2A in epilepsy susceptibility and drug response.     

Structure−function studies on the amphibian peptide brevinin 1E: translocating the cationic segment from the C‐terminal end to a central position favors selective antibacterial activity

Abstract: Brevinin 1E, which has the sequence FLPLLAGLAANFLPKIFCKITRKC , is an antimicrobial peptide isolated from the skin secretions of the European frog Rana esculenta. Both the linear and the disulfide‐bridged forms have relatively broad‐spectrum antibacterial as well as hemolytic activities. The antibacterial and hemolytic activities and biophysical properties of synthetic peptides corresponding to brevinin 1E and its analog in which the segment CKITRKC has been transposed to a central location resulting in the sequence FLPLLAGLCKITRKC AANFLPKIF have been investigated. Our studies indicate that the analog peptide has antibacterial activity comparable with brevinin 1E, but with considerably reduced hemolytic activity. The linear variant of the analog has no hemolytic activity, unlike the linear form of brevinin 1E. The biological activities can be explained on the basis of relative affinities for anionic and zwitterionic lipids. A cluster of cationic amino acids flanked on one side by a hydrophobic stretch of amino acids and another side composed of apolar amino acids appears to favor preferential antibacterial activity.     

Distress overlaps with anxiety and depression in patients with head and neck cancer

Psychological problems in cancer patients often go unrecognized until they are specifically sought. This is more in patients with depression as they are reluctant to complain about their symptoms. The present study was carried out to evaluate the relation of distress with anxiety and depression in 123 patients with head and neck cancers using Distress Inventory for Cancer version 2 (DIC2) and the Hospital Anxiety and Depression scale (HADS). The mean DIC 2 scores were 24.6 while that of subscales ranged from 2.6 to 11.0. Fifteen patients were found to have clinical caseness for anxiety while 12 (10%) were caseness for depression. Total distress, emotional and social distress subscales were found to have positive correlation with anxiety and depression suggesting a possible overlap of two constructs. In multivariate analysis only belief in god was found to significantly affect the distress. Results of present study suggest significant psychological morbidity in head neck cancer patients undergoing curative treatment. This is the first study reporting on the psychometric properties of distress inventory on cancer version 2 since its validation, the results suggest a possible overlap of two constructs similar to that seen with other tools on distress and this may have major implications for clinical practice.     

Role of improved distance and near visual acuity with low vision aids to enhance stereopsis in retinal diseases

Purpose:The purpose of this study was to examine role of improved distance and near best-corrected visual acuity (DBCVA and NBCVA) with use of magnification devices to enhance stereopsis in low vision (LV) subjects having retinal diseases.Methods:In a cross-sectional observational study without control, 84 subjects having LV due to retinal diseases were examined for an improvement of BCVA with use of magnifying low vision aids (LVAs) (2X for DBCVA and 3X for NBCVA). The stereopsis scores on titmus fly test were recorded with near refractive correction “on” and then with 3X magnification. The improvement in stereopsis for distance was however estimated through statistical correlation values.Results:The DBCVA (P < 0.001), NBCVA (P < 0.001) and stereopsis (P < 0.001) improved statistically significantly (SS) following magnifying LVA. There was no correlation between pre-LVA stereopsis and pre-LVA DBCVA (r = 0.059; P = 0.444;NSS) and post-LVA DBCVA (r = 0.054; P = 0.487;NSS); and no correlation between post-LVA stereopsis and pre-LVA DBCVA (r = 0.042; P = 0.592;NSS) and post-LVA DBCVA (r = 0.08; P = 0.920;NSS). There was no correlation between pre-LVA stereopsis and pre-LVA NBCVA (r = 0.044; P = 0.572;NSS) and no correlation between post-LVA stereopsis and pre-LVA NBCVA (r = 0.108; P = 0.165;NSS). But positive correlation between pre-LVA stereopsis and post-LVA NBCVA (r = 0.347; P < 0.001) and between post-LVA stereopsis and post-LVA NBCVA (r = 0.445; P < 0.001) was SS.Conclusion:The use of magnification as LVA improves both the BCVA and stereopsis. The increase in DBCVA with LVA improves the stereopsis for distance though it may not be SS while improvement in NBCVA with LVA enhances stereopsis for near objects in SS manner.     

Clinical profile and magnitude of diabetic retinopathy: An electronic medical record–driven big data analytics from an eye care network in India

Purpose:This study aimed to describe the clinical profile and magnitude of diabetic retinopathy (DR) in patients presenting to a multitier eye hospital network in India.Methods:This cross-sectional hospital-based study included 263,419 individuals with diabetes mellitus (DM) presenting between February 2012 and February 2021 (9-year period). The data were collected using an electronic medical record (EMR). Patients with a clinical diagnosis of DR in at least one eye were included in the analysis. Severe nonproliferative DR/proliferative DR/diabetic macular edema (DME) were considered sight-threatening DR (STDR).Results:In the study period, 25% (n = 66,913) were new patients diagnosed with DR. The majority of patients were males (70%). The mean age of the patients was 57 ± 10 years. The risk factors for DR were increased age: 30 to 50 years (odds ratio [OR] = 2.42), and 51 to 70 years (OR = 3.02), increased duration of DM: 6 to 10 years (OR = 2.88) and >10 years (OR = 6.52), blindness (OR = 2.42), male gender (OR = 1.36), lower socioeconomic status (OR = 1.43), and rural habitation (OR = 1.09). STDR was seen in 58% (n = 38,538) of examined patients. Risk factors for STDR were increased age 31 to 50 years (OR = 3.51), increased duration of DM: 6 to 10 years (OR = 1.23) and >10 years (OR = 1.68), blindness (OR = 3.68), male gender (OR = 1.12), and higher socioeconomic status (OR = 1.09).Conclusion:Every fourth person with DM was found to have DR, and every second person with DR had STDR in this study cohort. These real-world big data might provide greater insight into the current status of DR. Additional big data from similar EMR-based sources will help in planning and resource allocation.