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1.
Plant Physiol ; 187(3): 1636-1652, 2021 11 03.
Article in English | MEDLINE | ID: mdl-34618074

ABSTRACT

Plant MICRORNA164 (miR164) plays diverse regulatory functions by post-transcriptional repression of certain NAM/ATAF/CUC-domain transcription factors. However, the involvement of miR164 in fleshy fruit development and ripening remains poorly understood. Here, de novo prediction of tomato (Solanum lycopersicum) MIR164 genes identified four genes (SlMIR164a-d), of which SlMIR164d has an atypically long pre-miRNA. The roles of the fruit expressed SlMIR164a, b, and d were studied by analysis of their Clustered Regularly Interspaced Short Palindromic Repeats mutants. The slmir164bCR mutant plants exhibited shoot and flower abnormalities characteristic of ectopic boundary specification, whereas the shoot and flower development of slmir164aCR and slmir164dCR mutants were indistinguishable from wild-type. Strikingly, the knockout of SlMIR164a practically eliminated sly-miR164 from the developing and ripening fruit pericarp. The sly-miR164-deficient slmir164aCR fruits were smaller than the wild-type, due to reduced pericarp cell division and expansion, and displayed intense red color and matte, instead of glossy appearance, upon ripening. We found that the fruit skin phenotypes were associated with morphologically abnormal outer epidermis and thicker cuticle. Quantitation of sly-miR164 target transcripts in slmir164aCR ripening fruits demonstrated the upregulation of SlNAM3 and SlNAM2. Specific expression of their miR164-resistant versions in the pericarp resulted in the formation of extremely small fruits with abnormal epidermis, highlighting the importance of their negative regulation by sly-miR164a. Taken together, our results demonstrate that SlMIR164a and SlMIR164b play specialized roles in development: SlMIR164b is required for shoot and flower boundary specification, and SlMIR164a is required for fruit growth including the expansion of its outer epidermis, which determines the properties of the fruit skin.


Subject(s)
CRISPR-Cas Systems , Fruit/growth & development , Genes, Plant , RNA, Plant/genetics , Solanum lycopersicum/genetics , Fruit/genetics , Solanum lycopersicum/growth & development , Solanum lycopersicum/metabolism , RNA, Plant/metabolism
2.
Plant Physiol ; 185(3): 969-984, 2021 04 02.
Article in English | MEDLINE | ID: mdl-33793903

ABSTRACT

Fruit set is established during and soon after fertilization of the ovules inside the quiescent ovary, but the signaling pathways involved remain obscure. The tomato (Solanum lycopersicum) CRISPR loss-of-function mutant of the transcription factor gene AGAMOUS-like6 (SlAGL6; slagl6CR-sg1) is capable of fertilization-independent setting of normal, yet seedless (parthenocarpic), fruit. To gain insight into the mechanism of fleshy fruit set, in this study, we investigated how slagl6CR-sg1 uncouples fruit set from fertilization. We found that mutant ovules were enlarged due to integument over-proliferation and failed to differentiate an endothelium, the integument's innermost layer, upon maturation. A causal relationship between slagl6 loss-of-function and these abnormal phenotypes is inferred from the observation that SlAGL6 is predominantly expressed in the immature ovule integument, and upon ovule maturation, its expression shifts to the endothelium. The transcriptome of unfertilized mutant ovules profoundly differs from that of wild-type and exhibits substantial overlap with the transcriptomes of fertilized ovules sporophytic tissues. One prominent upregulated gene was the fertilization-induced cytochrome P450 cell proliferation regulator SlKLUH. Indeed, ectopic overexpression of SlKLUH stimulated both integument growth in unfertilized ovules and parthenocarpy, suggesting that its suppression by SlAGL6 is paramount for preventing fertilization-independent fruit set. Taken together, our study informs on the transcriptional programs that are regulated by SlAGL6 and demonstrates that it acts from within the ovule integument to inhibit ovary growth beyond anthesis. That by suppressing components of the fertilization-induced ovule reprogramming underlying fruit set.


Subject(s)
Fruit/metabolism , Ovule/metabolism , Solanum lycopersicum/metabolism , Flowers/metabolism , Flowers/physiology , Fruit/genetics , Gene Expression Regulation, Plant/genetics , Gene Expression Regulation, Plant/physiology , Solanum lycopersicum/genetics , Ovule/genetics
3.
Int J Mol Sci ; 22(9)2021 Apr 28.
Article in English | MEDLINE | ID: mdl-33925088

ABSTRACT

MicroRNA172 (miR172) functions as a central regulator of flowering time and flower development by post-transcriptional repression of APETALA2-LIKE transcription factors. In the model crop Solanum lycopersicum (tomato), the miR172 family is still poorly annotated and information about the functions of specific members is lacking. Here, de-novo prediction of tomato miR172 coding loci identified seven genes (SlMIR172a-g), that code for four unique species of miR172 (sly-miR172). During reproductive development, sly-miR172s are differentially expressed, with sly-miR172c and sly-miR172d being the most abundant members in developing flowers, and are predicted to guide the cleavage of eight APETALA2-LIKE transcription factors. By CRISPR-Cas9 co-targeting of SlMIR172c and SlMIR172d we have generated a battery of loss-of-function and hypomorphic mutants (slmir172c-dCR). The slmir172c-dCR plants developed normal shoot but their flowers displayed graded floral organ abnormalities. Whereas slmir172cCR loss-of-function caused only a slight greening of petals and stamens, hypomorphic and loss-of-function slmir172dCR alleles were associated with the conversion of petals and stamens to sepaloids, which were produced in excess. Interestingly, the degrees of floral organ identity alteration and proliferation were directly correlated with the reduction in sly-miR172d activity. These results suggest that sly-miR172d regulates in a dose-dependent manner floral organ identity and number, likely by negatively regulating its APETALA2-like targets.


Subject(s)
MicroRNAs/genetics , RNA, Plant/genetics , Solanum lycopersicum/growth & development , Solanum lycopersicum/genetics , Arabidopsis/genetics , Arabidopsis/growth & development , Base Sequence , CRISPR-Cas Systems , Flowers/genetics , Flowers/growth & development , Gene Expression Regulation, Developmental , Gene Expression Regulation, Plant , Genes, Plant , MicroRNAs/chemistry , Mutation , Nucleic Acid Conformation , Phenotype , Phylogeny , Plant Leaves/genetics , Plant Leaves/growth & development , Plants, Genetically Modified , RNA, Plant/chemistry
4.
Int Ophthalmol ; 40(1): 159-168, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31456155

ABSTRACT

PURPOSE: The current study was conducted to explore the potential of rutin in preventing sight-threatening diabetic retinopathy. METHODS: Wistar albino rats (either sex) weighing 200-225 g were intraperitoneally injected with 45 mg/kg streptozotocin (pH 4.5). Rats having blood glucose ≥ 300 mg/dL were divided into two groups (n = 8; each group). Group I served as diabetic control and received normal saline p.o. Group II received rutin 50 mg/kg p.o. for 24 weeks. At the end of 24 weeks, retinal fundus and fluorescein imaging were done, rats were killed, and retinal biochemical assessments were conducted. Moreover, ocular pharmacokinetics of rutin was assessed in the normal rats after a single oral dose of 50 mg/kg. RESULTS: Rutin treatment significantly (p < 0.001) lowered retinal vascular endothelial growth factor, tumor necrosis factor-α, and aldose reductase. Rutin treatment significantly (p < 0.001) elevated the levels of total antioxidant capacity of the retinas. Fundus examination of rutin-treated group showed significantly lower tortuosity index and normal fluorescein angiography. Rutin was detected in the retina as well as in aqueous humor of normal rats. CONCLUSION: Rutin treatment significantly arrested the biochemical disturbances of diabetic retinopathy. The distribution of orally ingested rutin in ocular tissues further substantiate its site-specific action.


Subject(s)
Aldehyde Reductase/metabolism , Antioxidants/metabolism , Diabetic Retinopathy/prevention & control , Retina/metabolism , Rutin/pharmacokinetics , Tumor Necrosis Factor-alpha/metabolism , Vascular Endothelial Growth Factor A/metabolism , Animals , Biomarkers/metabolism , Diabetes Mellitus, Experimental , Diabetic Retinopathy/diagnosis , Diabetic Retinopathy/metabolism , Female , Fluorescein Angiography/methods , Fundus Oculi , Male , Rats , Rats, Wistar , Retina/pathology
5.
Perspect Clin Res ; 9(4): 170-174, 2018.
Article in English | MEDLINE | ID: mdl-30319947

ABSTRACT

The primary focus of the pharmacovigilance (PV) practice has been on the collection, assessment, and reporting of the adverse drug reactions to medicinal products. Globalization of the pharmaceutical industry has prompted efforts to toward harmonization of PV practices worldwide to enable improved knowledge of medicine's benefit-risk profile and risk communication. Even as PV has evolved over the past decade, there still exist few areas of discordance across global PV practices. This article compares the PV legislation in the United States, United Kingdom, Canada, and India with a view to understand areas of harmony in the current legislation across regions and further compare health authorities' requirements with recommendations made by international organizations. Identification of potential areas of disharmony would pave the way to design solutions and strategies toward creation of a comprehensive PV system, which can be easily implemented across the globe, thus promoting the safer use of medicines.

6.
Plant J ; 96(4): 855-868, 2018 11.
Article in English | MEDLINE | ID: mdl-30144341

ABSTRACT

miR160 adjusts auxin-mediated development by post-transcriptional regulation of the auxin response factors ARF10/16/17. In tomato, knockdown of miR160 (sly-miR160) suggested that it is required for auxin-driven leaf blade outgrowth, but whether additional developmental events are adjusted by sly-miR160 is not clear. Here, the SlMIR160 genes and the genes of its SlARFs targets were edited by CRISPR/Cas9 resulting in the isolation of loss-of-function mutants. In addition, hypomorphic mutants that accumulate variable reduced levels of sly-miR160a were isolated. We found that the loss-of-function mutants in SlMIR160a (CR-slmir160a-6/7) produced only four wiry leaves, whereas the hypomorphic mutants developed leaves and flowers with graded developmental abnormalities. Phenotypic severity correlated with the upregulation of SlARF10A. Consistent with that, double mutants in SlMIR160a and SlARF10A restored leaf and flower development indicating that over-accumulation of SlARF10A underlay the developmental abnormalities exhibited in the CR-slmir160a mutants. Phenotype severity also correlated with the upregulation of the SHOOT MERISTEMLESS homolog Tomato Knotted 2, which in turn activated the transcription of the cytokinin biosynthesis genes SlIPT2 and SlIPT4. However, no change in Tomato Knotted 2 was detected in the absence of SlARF10A, suggesting that it is upregulated due to auxin signaling suppression by SlARF10A. Knockout of sly-miR160a-targeted SlARFs showed that whereas SlARF10A is indispensable for leaf blade outgrowth and floral organ patterning, the functions of SlARF16A and SlARF17 are redundant. Taken together our results suggest that sly-miR160a promotes blade outgrowth as well as leaf and leaflet initiation and floral organ development through the quantitative regulation of its major target SlARF10A.


Subject(s)
Flowers/genetics , Flowers/metabolism , Indoleacetic Acids/metabolism , MicroRNAs/genetics , Plant Leaves/genetics , Plant Leaves/metabolism , Solanum lycopersicum/genetics , Solanum lycopersicum/metabolism , Arabidopsis Proteins , CRISPR-Cas Systems , Cytokinins/genetics , Cytokinins/metabolism , Flowers/growth & development , Gene Expression Regulation, Developmental , Gene Expression Regulation, Plant , Gene Knockdown Techniques , Solanum lycopersicum/growth & development , MicroRNAs/physiology , Mutation , Phenotype , Plant Leaves/growth & development , Plant Proteins/genetics , Plant Proteins/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Transcriptome , Up-Regulation
7.
BMJ Case Rep ; 20162016 Oct 13.
Article in English | MEDLINE | ID: mdl-27737870

ABSTRACT

A man aged 30 years presented to the emergency department (ED) with ataxia, areflexia, facial weakness, ophthalmoplegia, extremity weakness and back pain for 4 days. 4 days prior to attending the ED, the patient had suffered from diarrhoea for 2 weeks. The diagnosis of Miller Fisher syndrome was performed on the dual basis of clinical features in addition to an investigations report. Nerve conduction studies and anti-GQ1b IgG antibody analysis were requested. Once IgA deficiency was ruled out, the patient was started on intravenous immunoglobulin (400 mg/kg/day).


Subject(s)
Immunoglobulins, Intravenous/therapeutic use , Miller Fisher Syndrome/therapy , Adult , Gangliosides/immunology , Humans , Immunoglobulin G/blood , Male , Miller Fisher Syndrome/diagnosis
8.
Mol Cell Biochem ; 420(1-2): 65-72, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27443845

ABSTRACT

Diabetic cardiomyopathy (DCM) is a dreadful complication of diabetes responsible for 80 % mortality in diabetic patients, but unfortunately its pharmacotherapy is still incomplete. Rutin is a naturally occurring flavonoid having a long history of use in nutritional supplements for its action against oxidative stress, inflammation, and hyperglycemia, the key players involved in the progression of DCM, but remains unexplored for its role in DCM. This study was conducted to address this lacuna. It was performed in 4-week-old Streptozotocin-induced (45 mg/kg) diabetic rats for a period of 24 weeks to mimic the cardiotoxic effect of chronic hyperglycemia in diabetic patient's heart and to investigate the effect of rutin (50 mg/kg/day) in ameliorating these effects. Heart of the diabetic rats showed altered ECG parameters, reduced total antioxidant capacity, increased inflammatory assault, and degenerative changes. Interestingly, rutin treatment significantly ameliorated these changes with decrease in blood glucose level (p > 0.001), % HbA1c (p > 0.001) and reduced expression of TNF-α (p < 0.001), CRP (p < 0.001), and BNP (p < 0.01) compared to diabetic control rats. In addition, rutin provided significant protection against diabetes associated oxidative stress (p < 0.05), prevented degenerative changes in heart, and improved ECG parameters compared to diabetic control rats. The heart-to-body weight ratio was significantly reduced in rutin treatment group compared to diabetic control rats (p < 0.001). In conclusion, this study implicates that oxidative stress and inflammation are the central players involved in the progression of DCM and rutin ameliorates DCM through its antioxidant and anti-inflammatory actions on heart.


Subject(s)
Antioxidants/pharmacology , C-Reactive Protein/metabolism , Cardiotonic Agents/pharmacology , Diabetes Mellitus, Experimental , Diabetic Cardiomyopathies , Natriuretic Peptide, Brain/blood , Rutin/pharmacology , Tumor Necrosis Factor-alpha/blood , Animals , Diabetes Mellitus, Experimental/blood , Diabetes Mellitus, Experimental/drug therapy , Diabetic Cardiomyopathies/blood , Diabetic Cardiomyopathies/drug therapy , Diabetic Cardiomyopathies/pathology , Female , Oxidative Stress/drug effects , Rats , Rats, Wistar
9.
PLoS One ; 11(4): e0152907, 2016.
Article in English | MEDLINE | ID: mdl-27077652

ABSTRACT

Domestication of tomato has resulted in large diversity in fruit phenotypes. An intensive phenotyping of 127 tomato accessions from 20 countries revealed extensive morphological diversity in fruit traits. The diversity in fruit traits clustered the accessions into nine classes and identified certain promising lines having desirable traits pertaining to total soluble salts (TSS), carotenoids, ripening index, weight and shape. Factor analysis of the morphometric data from Tomato Analyzer showed that the fruit shape is a complex trait shared by several factors. The 100% variance between round and flat fruit shapes was explained by one discriminant function having a canonical correlation of 0.874 by stepwise discriminant analysis. A set of 10 genes (ACS2, COP1, CYC-B, RIN, MSH2, NAC-NOR, PHOT1, PHYA, PHYB and PSY1) involved in various plant developmental processes were screened for SNP polymorphism by EcoTILLING. The genetic diversity in these genes revealed a total of 36 non-synonymous and 18 synonymous changes leading to the identification of 28 haplotypes. The average frequency of polymorphism across the genes was 0.038/Kb. Significant negative Tajima'D statistic in two of the genes, ACS2 and PHOT1 indicated the presence of rare alleles in low frequency. Our study indicates that while there is low polymorphic diversity in the genes regulating plant development, the population shows wider phenotype diversity. Nonetheless, morphological and genetic diversity of the present collection can be further exploited as potential resources in future.


Subject(s)
Fruit/growth & development , Fruit/genetics , Genomics , Phenotype , Polymorphism, Single Nucleotide , Solanum lycopersicum/growth & development , Solanum lycopersicum/genetics , Fruit/metabolism , Genes, Plant/genetics , Solanum lycopersicum/metabolism
10.
J Family Med Prim Care ; 5(4): 868-870, 2016.
Article in English | MEDLINE | ID: mdl-28349009

ABSTRACT

A 64-year-old African-American female presented with nonbloody nipple discharge. Clinical and cytological examination of the discharge was normal. The mammography suggested pleomorphic calcification in the left breast. A stereotactic biopsy showed ductal carcinoma in situ and her estrogen receptor/progesterone receptor/human epidermal growth factor receptor 2-neu receptor were negative. We removed the tumor tissue through lumpectomy and found that the mass was invasive ductal carcinoma. This case report highlights invasive ductal carcinoma, presenting with unilateral nipple discharge.

11.
Eye Brain ; 8: 1-13, 2016.
Article in English | MEDLINE | ID: mdl-28539797

ABSTRACT

Diabetic retinopathy is a highly specific microvascular complication of diabetes and a leading cause of blindness worldwide. It is triggered by hyperglycemia which causes increased oxidative stress leading to an adaptive inflammatory assault to the neuroretinal tissue and microvasculature. Prolonged hyperglycemia causes increased polyol pathway flux, increased formation of advanced glycation end-products, abnormal activation of signaling cascades such as activation of protein kinase C (PKC) pathway, increased hexosamine pathway flux, and peripheral nerve damage. All these changes lead to increased oxidative stress and inflammatory assault to the retina resulting in structural and functional changes. In addition, neuroretinal alterations affect diabetes progression. The most effective way to manage diabetic retinopathy is by primary prevention such as hyperglycemia control. While the current mainstay for the management of severe and proliferative diabetic retinopathy is laser photocoagulation, its role is diminishing with the development of newer drugs including corticosteroids, antioxidants, and antiangiogenic and anti-VEGF agents which work as an adjunct to laser therapy or independently. The current pharmacotherapy of diabetic retinopathy is incomplete as a sole treatment option in view of limited efficacy and short-term effect. There is a definite clinical need to develop new pharmacological therapies for diabetic retinopathy, particularly ones which would be effective through the oral route and help recover lost vision. The increasing understanding of the mechanisms of diabetic retinopathy and its biomarkers is likely to help generate better and more effective medications.

12.
Exp Eye Res ; 125: 193-202, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24952278

ABSTRACT

The aim of the present study was to evaluate the effects of Quercetin (Qctn), a plant based flavonol, on retinal oxidative stress, neuroinflammation and apoptosis in streptozotocin-induced diabetic rats. Qctn treatment (25- and 50 mg/kg body weight) was given orally for six months in diabetic rats. Retinal glutathione (GSH) and antioxidant enzymes [superoxide dismutase (SOD) and catalase (CAT)] were estimated using commercially available assays, and inflammatory cytokines levels [tumor necrosis factor-α (TNF-α), Interleukin-1ß (IL-1ß)] were estimated by ELISA method. Immunofluorescence and western blot studies were performed for nuclear factor kappa B (NF-kB), caspase-3, glial fibrillary acidic protein (GFAP) and aquaporin-4 (AQP4) expressions. Structural changes were evaluated by light microscopy. In the present study, retinal GSH levels and antioxidant enzyme (SOD and CAT) activities were significantly decreased in diabetic group as compared to normal group. However, in Qctn-treated rats, retinal GSH levels were restored close to normal levels and positive modulation of antioxidant enzyme activities was observed. Diabetic retinas showed significantly increased expression of pro-inflammatory cytokines (TNF-α and IL-1ß) as compared to that in normal retinas, while Qctn-treated retinas showed significantly lower levels of cytokines as compared to diabetic retinas. Light microscopy showed significantly increased number of ganglion cell death and decreased retinal thickness in diabetic group compared to those in normal retina; however, protective effect of Qctn was seen. Increased apoptosis in diabetic retina is proposed to be mediated by overexpression of NF-kB and caspase-3. However, Qctn showed inhibitory effects on NF-kB and caspase-3 expression. Microglia showed upregulated GFAP expression, and inflammation of Müller cells resulted in edema in their endfeet and around perivascular space in nerve fiber layer in diabetic retina, as observed through AQP4 expression. However, Qctn treatments inhibited diabetes-induced increases in GFAP and AQP4 expression. Based on these findings, it can be concluded that bioflavonoids, such as Qctn can be effective for protection of diabetes induced retinal neurodegeneration and oxidative stress.


Subject(s)
Antioxidants/pharmacology , Diabetes Mellitus, Experimental/drug therapy , Diabetic Retinopathy/drug therapy , Neuroprotective Agents/pharmacology , Quercetin/pharmacology , Retina/drug effects , Analysis of Variance , Animals , Antioxidants/metabolism , Apoptosis/drug effects , Aquaporin 4/metabolism , Caspase 3/metabolism , Catalase/metabolism , Diabetes Mellitus, Experimental/chemically induced , Diabetes Mellitus, Experimental/metabolism , Diabetic Retinopathy/metabolism , Glutathione/metabolism , Interleukin-1beta/metabolism , Male , Microglia/metabolism , Oxidative Stress/drug effects , Rats , Rats, Wistar , Retina/metabolism , Superoxide Dismutase/metabolism , Tumor Necrosis Factor-alpha/metabolism
13.
Plant Cell Environ ; 37(7): 1688-702, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24433205

ABSTRACT

Tomato fruit ripening is a complex metabolic process regulated by a genetical hierarchy. A subset of this process is also modulated by light signalling, as mutants encoding negative regulators of phytochrome signal transduction show higher accumulation of carotenoids. In tomato, phytochromes are encoded by a multi-gene family, namely PHYA, PHYB1, PHYB2, PHYE and PHYF; however, their contribution to fruit development and ripening has not been examined. Using single phytochrome mutants phyA, phyB1 and phyB2 and multiple mutants phyAB1, phyB1B2 and phyAB1B2, we compared the on-vine transitory phases of ripening until fruit abscission. The phyAB1B2 mutant showed accelerated transitions during ripening, with shortest time to fruit abscission. Comparison of transition intervals in mutants indicated a phase-specific influence of different phytochrome species either singly or in combination on the ripening process. Examination of off-vine ripened fruits indicated that ripening-specific carotenoid accumulation was not obligatorily dependent upon light and even dark-incubated fruits accumulated carotenoids. The accumulation of transcripts and carotenoids in off-vine and on-vine ripened mutant fruits indicated a complex and shifting phase-dependent modulation by phytochromes. Our results indicate that, in addition to regulating carotenoid levels in tomato fruits, phytochromes also regulate the time required for phase transitions during ripening.


Subject(s)
Fruit/growth & development , Fruit/metabolism , Phytochrome/metabolism , Solanum lycopersicum/growth & development , Solanum lycopersicum/metabolism , Biosynthetic Pathways/genetics , Carotenoids/metabolism , Chlorophyll/metabolism , Ethylenes/metabolism , Fruit/genetics , Gene Expression Regulation, Plant , Solanum lycopersicum/genetics , Mutation/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Time Factors
14.
Mol Cell Biochem ; 388(1-2): 1-9, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24242137

ABSTRACT

The aim of the present study was to investigate the protective effects of Trigonella foenum-graecum Linn. (fenugreek) in Streptozotocin-induced diabetic rat retina. Fenugreek (100 and 200 mg/kg body weights) treatment was carried out for 24 weeks and evaluated for inflammatory [tumor necrosis factor (TNF)-α and interleukin (IL)-1ß] and angiogenic [vascular endothelial growth factor (VEGF) and protein kinase C (PKC)-ß] molecular biomarkers. Retinal oxidative stress was evaluated by estimating antioxidant (Glutathione, Superoxide dismutase, and Catalase) parameters. Fluorescein angiography was performed to detect retinal vascular leakage. Electron microscopy was performed to determine basement membrane thickness. In the present study, significant rises in the expressions of retinal inflammatory (TNF-α and IL-1ß) and angiogenic (VEGF and PKC-ß) molecular biomarkers were observed in diabetic retinae compared with normal retinae. However, fenugreek-treated retinae showed marked inhibition in the expression of inflammatory and angiogenic molecular biomarkers. Moreover, results from the present study showed positive modulatory effects of fenugreek on retinal oxidative stress. Fluorescein angiograms and fundus photographs obtained from diabetic retinae showed retinal vascular leakage. On the other hand, fenugreek-treated retinae did not show vascular leakage. Further, thickened BM was recorded in diabetic retina compared with normal retinae. However, fenugreek-treated retinae showed relatively lesser thickening of capillary BM. In conclusion, it may be postulated that fenugreek has great potential in preventing diabetes-induced retinal degeneration in humans after regular consumption in the specified dosage.


Subject(s)
Diabetes Mellitus, Experimental/drug therapy , Diabetic Retinopathy/prevention & control , Oxidative Stress/drug effects , Retinal Degeneration/prevention & control , Trigonella/metabolism , Animals , Anti-Inflammatory Agents/therapeutic use , Antioxidants/therapeutic use , Catalase/biosynthesis , Glutathione/biosynthesis , Inflammation/drug therapy , Interleukin-1beta/biosynthesis , Neovascularization, Pathologic/drug therapy , Phytotherapy , Plant Preparations/therapeutic use , Protein Kinase C beta/biosynthesis , Rats , Rats, Wistar , Retina/pathology , Retinal Vasculitis/prevention & control , Streptozocin , Superoxide Dismutase/biosynthesis , Tumor Necrosis Factor-alpha/biosynthesis , Vascular Endothelial Growth Factor A/biosynthesis
15.
Microvasc Res ; 87: 65-74, 2013 May.
Article in English | MEDLINE | ID: mdl-23376836

ABSTRACT

The purpose of the study was to evaluate the effects of hesperetin (Hsp) on diabetes-induced retinal oxidative stress, neuroinflammation and apoptosis in rats. The Hsp treatment (100 mg/kg body weight) was carried for twenty four weeks in STZ-induced diabetic rats and evaluated for antioxidant (Superoxide dismutase; SOD, Catalase; CAT and glutathione; GSH) enzymes, inflammatory cytokines (TNF-α, IL-1ß), caspase-3, glial fibrillary acidic protein (GFAP) and aquaporin-4(AQP4) expression. Histological changes were evaluated by light and transmission electron microscopic (LM and TEM) studies. Retinal GSH levels and anti-oxidant enzymes (SOD and CAT) activity were significantly decreased in diabetic group as compared to normal group. However, in Hsp-treated rats, retinal GSH levels were restored close to normal levels and positive modulation of anti-oxidant enzyme activity was observed. Diabetic retinae showed significantly increased expression of Pro-inflammatory cytokines (TNF-α and IL-1ß) as compared to normal retinae. While Hsp-treated retinae showed significantly lower levels of cytokines as compared to diabetic retinae. Diabetic retinae showed increased caspase-3, GFAP and AQP4 expression. However, Hsp-treated retinae showed inhibitory effect on caspase-3, GFAP and AQP4 expression. LM images showed edematous Müller cell endfeet, and also degenerated photoreceptor layer; however, protective effect of Hsp was seen on Müller cell processes and photoreceptors. TEM study showed increased basement membrane (BM) thickness in diabetic retina, while relatively thin BM was recorded in Hsp-treated retina. It can be postulated that dietary flavanoids, like Hsp, can be effective for the prevention of diabetes induced neurovascular complications such as diabetic retinopathy.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Apoptosis/drug effects , Diabetes Mellitus, Experimental/drug therapy , Diabetic Retinopathy/drug therapy , Hesperidin/pharmacology , Inflammation/drug therapy , Oxidative Stress/drug effects , Retina/drug effects , Animals , Aquaporin 4/metabolism , Blood Glucose/drug effects , Blood Glucose/metabolism , Body Weight/drug effects , Caspase 3/metabolism , Catalase/metabolism , Diabetes Mellitus, Experimental/chemically induced , Diabetes Mellitus, Experimental/immunology , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Experimental/pathology , Diabetic Retinopathy/immunology , Diabetic Retinopathy/metabolism , Diabetic Retinopathy/pathology , Female , Glial Fibrillary Acidic Protein/metabolism , Glutathione/metabolism , Immunohistochemistry , Inflammation/immunology , Inflammation/metabolism , Inflammation/pathology , Inflammation Mediators/metabolism , Interleukin-1beta/metabolism , Male , Microscopy, Electron, Transmission , Rats , Rats, Wistar , Retina/immunology , Retina/metabolism , Retina/ultrastructure , Streptozocin , Superoxide Dismutase/metabolism , Time Factors , Tumor Necrosis Factor-alpha/metabolism
16.
Vascul Pharmacol ; 57(5-6): 201-7, 2012.
Article in English | MEDLINE | ID: mdl-22967957

ABSTRACT

The purpose of the study was to evaluate vasculoprotective effects of Hesperetin (Hsp) in Streptozotocin induced diabetic rats. The study was carried out for a period of 24weeks and evaluated for angiogenic parameters (VEGF and PKC-ß), retinal vascular leakage by fluorescein angiography and, vessel (arteriolar and venular) diameters and any morphological abnormality through fundus photographs. Apart from this, transmission electron microscopy (TEM) was done to determine capillary basement membrane (BM) thickness. The results of the present study showed a significant increase in the expression of VEGF and PKC-ß in diabetic retinae as compared to normal retinae. On the other hand, Hsp-treated retinae showed marked inhibition in the expression of VEGF and PKC-ß. In the present study, diabetic retinae showed increase vascular permeability and leakage as compared to normal retinae. However, Hsp-treated retinae have not shown any such vascular dysfunctions. Moreover, there was significant increase in vessel caliber recorded in diabetic retinae compared to normal retinae, on the contrary Hsp-treated retinae showed lesser dilated vessels. Further, TEM study showed thickened BM in diabetic group as compared to normal group. However, Hsp-treated retinae showed marked prevention in BM thickness. In conclusion, it can be sated that Hsp has potential vasoprotective effects and can be useful in preventing diabetes induced vasculopathy.


Subject(s)
Diabetes Mellitus, Experimental/drug therapy , Diabetic Retinopathy/prevention & control , Hesperidin/pharmacology , Hyperglycemia/drug therapy , Angiogenesis Inhibitors/pharmacology , Animals , Basement Membrane/drug effects , Basement Membrane/metabolism , Diabetes Mellitus, Experimental/complications , Diabetic Retinopathy/etiology , Diabetic Retinopathy/pathology , Fluorescein Angiography , Gene Expression Regulation , Hyperglycemia/complications , Microscopy, Electron, Transmission , Protein Kinase C/genetics , Protein Kinase C/metabolism , Protein Kinase C beta , Rats , Rats, Wistar , Retinal Neovascularization/drug therapy , Retinal Neovascularization/pathology , Vascular Endothelial Growth Factor A/genetics , Vascular Endothelial Growth Factor A/metabolism
17.
Ophthalmic Res ; 47(2): 103-8, 2012.
Article in English | MEDLINE | ID: mdl-21997135

ABSTRACT

PURPOSE: Our objective was to investigate the effect of green tea (GT) on diabetes-induced retinal oxidative stress and proinflammatory parameters in rats. METHODS: Treatment (200 mg/kg body weight) was carried out for a period of 16 weeks in streptozotocin-induced diabetic rats and was evaluated for hypoglycemic, antioxidant [reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT)] and anti-inflammatory [tumor necrosis factor (TNF) α, vascular endothelial growth factor (VEGF)] activity. Histological changes were evaluated by transmission electron microscopy. RESULTS: Retinal GSH levels were 1.5-fold lower in diabetic rats as compared to normal rats (p < 0.05). However, in GT-treated rats, retinal GSH levels were restored close to those of the normal group. The antioxidant enzymes SOD and CAT showed a more than 2-fold decrease in activity in diabetic retinae as compared to normal retinae (p < 0.05). Both SOD and CAT enzymatic activities were restored close to normal in the GT-treated group. Expression of proinflammatory parameters (TNF-α and VEGF) was significantly inhibited in GT-treated retinae as compared to diabetic retinae (p < 0.05). Moreover, GT treatment prevented retinal capillary basement membrane thickness. CONCLUSION: The beneficial effects of GT suggest its potential role in the prevention and treatment of diabetic retinopathy in human subjects.


Subject(s)
Antioxidants/pharmacology , Diabetes Mellitus, Experimental/metabolism , Oxidative Stress/drug effects , Plant Extracts/pharmacology , Retina/drug effects , Tea/chemistry , Animals , Catalase/metabolism , Glutathione/metabolism , Glycemic Index/drug effects , Male , Microscopy, Electron, Transmission , Rats , Rats, Wistar , Retina/metabolism , Superoxide Dismutase/metabolism , Tumor Necrosis Factor-alpha/metabolism , Vascular Endothelial Growth Factor A/metabolism
18.
Arzneimittelforschung ; 61(5): 312-6, 2011.
Article in English | MEDLINE | ID: mdl-21755815

ABSTRACT

Combination of disease-modifying antirheumatic drugs (DMARDs) is increasingly used in the treatment of rheumatoid arthritis (RA) patients. Hepatotoxicity has been an important safety concern with DMARDs therapy. Though leflunomide (CAS 75706-12-6) has emerged as an effective oral DMARD, its use is associated with hepatotoxicity. Limited data is available regarding hepatotoxic risk when leflunomide is used in combination therapy in RA patients. An open-label, prospective study was conducted to evaluate the hepatotoxic risk after addition of leflunomide with other DMARDs in RA patients, who did not respond to their ongoing DMARD therapy. A total of 46 patients were enrolled and leflunomide was given as add-on therapy with earlier DMARDs. Biochemical parameters of serum aminotransferase levels (AST and ALT) were estimated at the baseline and then every month after addition of leflunomide. Study results showed that 13.0% patients developed > 1.5 to < 2 times upper limit of normal (ULN) elevation; 6.5% patients developed > 2 to < 3 times the ULN elevation and 2.2% patients developed > 3 times the ULN elevation. In 20% of the patients with hepatic enzyme elevations, enzyme levels returned to normal within 4-6 weeks after discontinuation of leflunomide therapy, whereas in 50% of patients the dose of leflunomide was reduced from 20 mg/day to 10 mg/day for normalization of enzymes levels. 30% of patients were continued with leflunomide without dose reduction. None of the patients showed clinical signs and symptoms of hepatotoxicity. Leflunomide therapy with other DMARDs requires strict monitoring of serum aminotransferases.


Subject(s)
Antirheumatic Agents/adverse effects , Arthritis, Rheumatoid/complications , Chemical and Drug Induced Liver Injury/epidemiology , Isoxazoles/adverse effects , Adult , Aged , Alanine Transaminase/blood , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Aspartate Aminotransferases/blood , Drug Therapy, Combination , Female , Humans , Isoxazoles/therapeutic use , Leflunomide , Male , Methotrexate/adverse effects , Methotrexate/therapeutic use , Middle Aged , Prospective Studies , Risk
19.
J Ocul Pharmacol Ther ; 27(2): 123-30, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21314438

ABSTRACT

PURPOSE: The purpose of this study was to evaluate the therapeutic potential of oral curcumin (1 g/kg body weight of rat) in the prevention and treatment of streptozotocin-induced diabetic retinopathy in Wistar albino rats. METHODS: The treatment was carried out for a period of 16 weeks in diabetic rats and evaluated for hyperglycemic, antioxidant (superoxide dismutase, catalase, and glutathione), and inflammatory parameters (tumor necrosis factor-α, vascular endothelial growth factor). Rat fundus was observed weekly to see any visible changes in the retina, such as tortuosity and dilation of retinal vessels. Histological changes were evaluated by transmission electron microscopy. RESULTS: Treatment with curcumin showed significant hypoglycemic activity compared with the diabetic group. Retinal glutathione levels were decreased by 1.5-fold, and antioxidant enzymes, superoxide dismutase and catalase, showed >2-fold decrease in activity in the diabetic group; on the other hand, curcumin positively modulated the antioxidant system. Proinflammatory cytokines, tumor necrosis factor-α and vascular endothelial growth factor, were elevated >2-fold in the diabetic retinae, but prevented by curcumin. Transmission electron microscopy showed degeneration of endothelial cell organelles and increase in capillary basement membrane thickness in diabetic retina, but curcumin prevented the structural degeneration and increase in capillary basement membrane thickness in the diabetic rat retinae. CONCLUSION: Based on the above results, it may be concluded that curcumin may have potential benefits in the prevention of retinopathy in diabetic patients.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Curcumin/pharmacology , Diabetes Mellitus, Experimental/drug therapy , Diabetic Retinopathy/prevention & control , Hypoglycemic Agents/pharmacology , Animals , Basement Membrane/pathology , Curcumin/therapeutic use , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/pathology , Male , Microscopy, Electron , Rats , Rats, Wistar , Retina/ultrastructure , Streptozocin , Tumor Necrosis Factor-alpha/analysis , Vascular Endothelial Growth Factor A/analysis
20.
Indian J Physiol Pharmacol ; 55(1): 5-12, 2011.
Article in English | MEDLINE | ID: mdl-22315805

ABSTRACT

Angiogenesis is controlled by number of growth factors, including vascular endothelial growth factor (VEGF). Plant derived anti-angiogenic molecules acting via VEGF are being investigated for curtailing angiogenesis dependent diseases. In this study, methanolic (CM), n-hexane (CH), ethylacetate (CE) and water (CW) extracts of the roots of Calotropis procera were tested for anti-angiogenic activity. In the chicken egg chorioallantoic membrane (CAM) assay, CM, CH and CE but not CW inhibited VEGF-induced neovascularization in a dose-dependent manner. Of all the tested extracts, CM at the dose of 10, 5 and 2.5 ng most effectively inhibited over 83, 71 and 64%, of neovascularization induced by 10ng of VEGF, respectively. Sponge implantation assay in mice further showed that at the dose of 100ng CM, CH and CE but not CW significantly inhibited neovascularization induced by VEGF (100 ng). Taken together, this study indicates that the root extracts of C. procera may possess anti-angiogenic activity.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Calotropis , Plant Extracts/pharmacology , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Animals , Calotropis/chemistry , Chick Embryo , Chorioallantoic Membrane/blood supply , Chorioallantoic Membrane/drug effects , Chromatography, High Pressure Liquid , Male , Mice , Plant Roots/chemistry
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