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1.
Int J Biol Macromol ; 275(Pt 1): 133566, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38960264

RESUMO

The present review elaborates on the details of the enzyme, its structure, specificity, and the mechanism of action of selected enzymes as well as structural changes and loss or gain of activity after non-thermal treatments for food-based applications. Enzymes are biological catalysts found in various systems such as plants, animals, and microorganisms. Most of the enzymes have their optimum pH, temperature, and substrate or group of substrates. The conformational modification of enzymes either increases or decreases the rate of reaction at different pH, and temperature conditions. Enzymes are modified by different techniques to enhance the activity of enzymes for their commercial applications mainly due to the high cost of enzymes, stability, and difficulties that occur during the use of enzymes in different conditions. On the opposite, enzyme inactivation provides its application to extend the shelf life of fruits and vegetables by denaturation and partial inactivation of enzymes. Hence, the activation and inactivation of enzymes are studied by non-thermal techniques in both the model and the food system. The highly reactive species generated during non-thermal techniques cause chemical and structural modification. The enzyme modifications depend on the type and source of the enzyme, type of technique, and the parameters used.

2.
Indian J Ophthalmol ; 70(10): 3650-3657, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36190066

RESUMO

Purpose: To analyze the hesitancy and motivational factors related to coronavirus disease 2019 (COVID-19) vaccination among patients visiting for eye care. Methods: A telephonic survey was conducted using validated questionnaires consisting of 36 questions in five sections from July 1 to July 31, 2021. Patients visiting six tertiary centers and one secondary center of our eye hospitals were interviewed over their phones, and their responses were entered onto the Google forms. The responses were recorded as demographics, health status, awareness about vaccination, factors contributing to hesitancy or acceptance to vaccinate, and general perception about the vaccine. Results: A total of 5033 patients were surveyed. The mean age was 49.0 ± 14.2 years. A total of 563 (11.2%) patients gave a history of symptoms or were tested positive for COVID-19; 2225 (44.2%) patients were already COVID-19 vaccinated. Around 2883 (56%) patients were aware of getting infection despite vaccination, and 4092 (81.3%) perceived vaccination should be compulsory. The main reason for vaccination hesitancy was the fear of side effects (n = 487, 17.3%). The fear of getting infected was the most common reason for vaccination (n = 911, 40.9%). Factors associated with a lower proportion of vaccinated individuals included younger age (P < 0.001), female gender (P < 0.001), lower education (P < 0.001), lower income (P < 0.001), and rural residence (P = 0.33). Conclusion: Creating awareness about the minor side effects and reassurance can allay an individual's fears. The fear associated with the rapid spread of infection and associated mortality needs to be utilized to increase vaccination acceptance. A targeted approach toward groups with poor uptake of vaccination is necessary.


Assuntos
COVID-19 , Vacinas , Adulto , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Hospitais , Humanos , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Inquéritos e Questionários , Vacinação
3.
Med Chem ; 18(9): 915-925, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35086456

RESUMO

Bioisosterism is a unique approach used by medicinal chemists for the reasonable modification of lead compounds into safer, more clinically effective, economical, and therapeutically attractive drugs. It is one of the most crucial lead modification tools, widely applied in the field of rational drug design to amplify the desired activity and eliminate undesirable properties, thus facilitating the optimization of pharmacokinetic profile and achievement of target selectivity. This review demonstrates the importance of bioisosterism in the process of drug discovery and development and highlights its relevance in the molecular evolution of many classes of drugs such as antibacterial sulfonamides, anticancer drugs, antivirals, antifungals, anthelmintics, local anesthetics, barbiturates, antidepressants, antihistamines, proton pump inhibitors and work carried out by our team of researchers. The role of bioisosterism as a strategy to achieve inhibition of enzymes such as thymidylate synthase, DNA polymerase, reverse transcriptase and several others has also been pointed out. There are no limits to the classes of drugs where bioisosterism has been successfully applied.


Assuntos
Antineoplásicos , Descoberta de Drogas , Antineoplásicos/farmacologia , Desenho de Fármacos
4.
Beilstein J Org Chem ; 17: 2680-2715, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34804240

RESUMO

Sugar-modified nucleosides have gained considerable attention in the scientific community, either for use as molecular probes or as therapeutic agents. When the methylene group of the ribose ring is replaced with a sulfur atom at the 3'-position, these compounds have proved to be structurally potent nucleoside analogues, and the best example is BCH-189. The majority of methods traditionally involves the chemical modification of nucleoside structures. It requires the creation of artificial sugars, which is accompanied by coupling nucleobases via N-glycosylation. However, over the last three decades, efforts were made for the synthesis of 1,3-oxathiolane nucleosides by selective N-glycosylation of carbohydrate precursors at C-1, and this approach has emerged as a strong alternative that allows simple modification. This review aims to provide a comprehensive overview on the reported methods in the literature to access 1,3-oxathiolane nucleosides. The first focus of this review is the construction of the 1,3-oxathiolane ring from different starting materials. The second focus involves the coupling of the 1,3-oxathiolane ring with different nucleobases in a way that only one isomer is produced in a stereoselective manner via N-glycosylation. An emphasis has been placed on the C-N-glycosidic bond constructed during the formation of the nucleoside analogue. The third focus is on the separation of enantiomers of 1,3-oxathiolane nucleosides via resolution methods. The chemical as well as enzymatic procedures are reviewed and segregated in this review for effective synthesis of 1,3-oxathiolane nucleoside analogues.

5.
J Appl Microbiol ; 128(2): 426-437, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31621139

RESUMO

AIM: The aim of this present study was to investigate the antifungal mechanism of sertraline against Candida auris (C. auris) and its effect on biofilm formation. METHODS AND RESULTS: Sertraline, a repurposing drug with a history of human use for the treatment of depression was screened against three different isolates of C. auris, and was found to possess efficient antifungal activity. The antifungal activity of sertraline was further confirmed by killing kinetics assay and post-antifungal effect (PAFE). Sertraline inhibited C. auris yeast to hyphae conversion and further the inhibition of biofilm formation showed 71% inhibition upon treatment. Cell damage caused due to C. auris after treatment with sertraline was observed using SEM and cell membrane damage was ascertained using flow cytometry by Propidium Iodide (PI) uptake assay. The results of sorbitol protection assay and ergosterol effect assay suggested that sertraline did not affect the cell wall and did not act by binding to membrane ergosterol. The mechanism of action of sertraline against C. auris was understood through in silico docking studies that revealed the binding nature of sertraline to the sterol 14 alpha demethylase which is involved in ergosterol biosynthesis. Ergosterol that was quantified from treated cells showed a 5·5-fold decrease in ergosterol production. CONCLUSION: Sertraline displayed promising antifungal activity against C. auris involved in candidiasis infection and the mechanism of action was predicted. SIGNIFICANCE AND IMPACT OF THIS STUDY: The results of this study can encourage for the development of new antifungal agents and can be promising antifungal agent against C. auris infection.


Assuntos
Antifúngicos/farmacologia , Biofilmes/efeitos dos fármacos , Candida/efeitos dos fármacos , Candidíase/microbiologia , Sertralina/farmacologia , Candida/crescimento & desenvolvimento , Candida/fisiologia , Ergosterol/metabolismo , Humanos , Testes de Sensibilidade Microbiana
6.
J Diabetes Complications ; 32(5): 524-530, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29530315

RESUMO

Diabetes is a chronic metabolic disorder that poses a global burden to healthcare. Increasing incidence of diabetes-related complications in the affected population includes a delay in wound healing that often results in non-traumatic limb amputations. Owing to the intricacies of the healing process and crosstalk between the multitude of participating cells, the identification of hyperglycaemia-induced changes at both cellular and molecular levels poses a challenge. Macrophages are one of the key participants in wound healing and continue to exert functional changes at the wound site since the time of injury. In the present review, we discuss the role of these cells and their aberrant functions in diabetic wounds. We have extensively studied the process of macrophage polarization (MP) and its modulation through epigenetic modifications. Data from both pre-clinical and clinical studies on diabetes have co-related hyperglycaemia induced changes in gene expression to an increased incidence of diabetic complications. Hyperglycaemia and oxidative stress, create an environment prone to changes in the epigenetic code, that is manifested as an altered inflammatory gene expression. Here, we have attempted to understand the different epigenetic modulations that possibly contribute towards dysregulated MP, resulting in delayed wound healing.


Assuntos
Polaridade Celular/genética , Complicações do Diabetes/fisiopatologia , Epigênese Genética/fisiologia , Ativação de Macrófagos/genética , Macrófagos/fisiologia , Cicatrização/genética , Animais , Complicações do Diabetes/genética , Complicações do Diabetes/imunologia , Complicações do Diabetes/metabolismo , Humanos , Pele/imunologia , Pele/lesões , Pele/metabolismo , Pele/patologia , Cicatrização/imunologia
7.
Adv Pharmacol Sci ; 2018: 4751806, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30687400

RESUMO

Alteration of epigenetic enzymes is associated with the pathophysiology of colon cancer with an overexpression of histone deacetylase 8 (HDAC8) enzyme in this tissue. Numerous reports suggest that targeting HDAC8 is a viable strategy for developing new anticancer drugs. Flavonols provide a rich source of molecules that are effective against cancer; however, their clinical use is limited. The present study investigated the potential of quercetin and synthetic 3-hydroxyflavone analogues to inhibit HDAC8 enzyme and evaluated their anticancer property. Synthesis of the analogues was carried out, and cytotoxicity was determined using MTT assay. Nonspecific and specific HDAC enzyme inhibition assays were performed followed by the expression studies of target proteins. Induction of apoptosis was studied through annexin V and caspase 3/7 activation assay. Furthermore, the analogues were assessed against in vivo colorectal cancer. Among the synthesized analogues, QMJ-2 and QMJ-5 were cytotoxic against HCT116 cells with an IC50 value of 68 ± 2.3 and 27.4 ± 1.8 µM, respectively. They inhibited HDAC enzyme in HCT116 cells at an IC50 value of 181.7 ± 22.04 and 70.2 ± 4.3 µM, respectively, and inhibited human HDAC8 and 1 enzyme at an IC50 value of <50 µM with QMJ-5 having greater specificity towards HDAC8. A reduction in the expression of HDAC8 and an increase in acetyl H3K9 expression were observed with the synthesized analogues. Both QMJ-2 and QMJ-5 treatment induced apoptosis through the activation of caspase 3/7 evident from 55.70% and 83.55% apoptotic cells, respectively. In vivo studies revealed a significant decrease in colon weight to length ratio in QMJ-2 and QMJ-5 treatment groups compared to DMH control. Furthermore, a reduction in aberrant crypt foci formation was observed in the treatment groups. The present study demonstrated the potential of novel 3-hydroxyflavone analogues as HDAC8 inhibitors with anticancer property against colorectal cancer.

8.
EXCLI J ; 16: 448-463, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28694750

RESUMO

Considering the therapeutic values of bioflavonoids in colon cancer treatment, six 2'-hydroxy chalcones (C1-C6) were synthesized, characterized and screened for in vitro cytotoxicity on human colon carcinoma (HCT116) and African green monkey kidney epithelial cells (Vero). Only C5 showed selective cytotoxicity against HCT116 cells. Other potent cytotoxic compounds were C1, C2 and C3. Further screening included enzyme inhibition studies on histone deacetylase (HDAC) enzyme where C1 showed lowest IC50 value (105.03 µM). Based on cytotoxicity data C1, C2 and C3 were selected for further in vitro mechanistic studies, namely apoptotic studies (Acridine orange/Ethidium bromide (AO/EB) and Annexin V), cell cycle analysis using propidium iodide (PI) stain and in vivo anticancer efficacy in 1,2-dimethyl hydrazine (DMH) induced colorectal carcinoma in Wistar rats. The compounds induced apoptosis in more than 30 % cells in AO/EB and Annexin V staining. They also showed cell cycle arrest in G2/M phase with PI staining. They showed a significant reduction in aberrant crypt foci formation and adenocarcinoma count along with a significant (p<0.05) reduction in TNF-α levels as compared to DMH control at 100 mg/kg dose. Thus, it can be concluded that the synthesized 2'-hydroxychalcones were effective against colon adenocarcinoma in in vitro and in vivo studies.

9.
Phytochemistry ; 136: 70-80, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28108024

RESUMO

Cancer is possibly one of the most devastating and complex disease and therefore involves chemotherapy as one of the frontline strategies in its therapy. However, expected toxicity and resistance with chemotherapeutic agents encourage us to use the plant derived natural chemotherapeutic sources at the clinical stage of cancer therapy. In view of this strategy, herein new glycosides and isoflavonoids were isolated from Iris kashmiriana Baker and subjected to structure elucidation followed by their biological evaluation. Isolated compounds and their derivatives were purified by the column chromatography and structural identification was made by a combination of various spectroscopic technique vis. UV, IR, 1H NMR, 13C NMR, DEPT, 2-D NMR and mass spectrometry coupled with chemical analysis. Furthermore, an in silico library of isolated isoflavones and its analogues were designed. NF-kappaB (transcription factor that facilitates angiogenesis, inflammation, invasion and metastasis) was selected as a target to evaluate the anticancer and antioxidant activity of isoflavones and its analogues. Designed library of isoflavones and analogues were docked into the active site of NF-kappa B and the most active 15 analogues were selected for synthesis. Finally, all compounds were evaluated for their cytotoxicity against various cell lines and antioxidant activity with different methods that demonstrate their anti-cancer and anti-oxidant potential. The cell cycle specificity of the cytotoxicity was further analyzed by corresponding analysis, using flow cytometer. Most of the compounds exhibit moderate activity, whereas the 5,7,8-trihydroxy-3-(4-methoxyphenyl)-4H-chromen-4-one, 5,7,8-trihydroxy-3-(4-hydroxyphenyl)-4H-chromen-4-one, 5,7,8-triacetoxyoxy-3-(4-methoxyphenyl)-4H-chromen-4-one and 6,7-diacetoxyoxy-3-(4-methoxyphenyl)-4H-chromen-4-one showed distinct broad-spectrum anticancer activity with IC50 values ranges between 3.8 and 5.6 µg/mL. Cell cycle analysis indicates that these compounds induced cell cycle arrest at G2/M phase.


Assuntos
Ansiolíticos/isolamento & purificação , Ansiolíticos/farmacologia , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Gênero Iris/química , Isoflavonas/isolamento & purificação , Isoflavonas/farmacologia , NF-kappa B/efeitos dos fármacos , Ansiolíticos/química , Antineoplásicos/química , Sobrevivência Celular/efeitos dos fármacos , Glicosídeos/farmacologia , Humanos , Isoflavonas/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
10.
J Mol Graph Model ; 72: 81-87, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28064082

RESUMO

Epigenetic modulation of gene expression has drawn enormous attention among researchers globally in the present scenario. Since their discovery, Jmj-C histone demethylases were identified as useful markers in understanding the role of epigenetics in inflammatory conditions and in cancer as well. This has created arousal of interest in search of suitable candidates. Potential inhibitors from various other scaffolds such as hydroxyquinolines, hydroxamic acids and triazolopyridines have already been identified and reported. In this direction, our present study attempts to target one of the important members of the family- namely JMJD3 (also known as KDM6B), that plays a pivotal role in inflammatory and immune reactions. Using molecular modeling approaches, myricetin analogues were identified as promising inhibitors of JMJD3. Extensive literature review showed myricetin as the most promising flavonol inhibitor for this enzyme. It served as a prototype for our study and modification of it's scaffold led to generation of analogues. The ZINC database was used as a repository for natural compounds and their analogues. Using similarity search options, 65 analogues of myricetin were identified and screened against JMJD3 (PDB ID: 4ASK), using the high throughput virtual screening and ligand docking tools in Maestro Molecular Modeling platform (version 10.5) from Schrödinger, LLC. 8 analogues out of 65 were identified as the most appropriate candidates which gave the best pose in ligand docking. Their binding mode and energy calculations were analysed using induced fit docking (IFD) and prime-MMGBSA tool, respectively. Thus, our findings highlight the most promising analogues of myricetin with comparable binding affinity as well as binding energy than their counterparts that could be taken for further optimisation as inhibitors of JMJD3 in both in vitro and in vivo screening studies.


Assuntos
Flavonoides/química , Flavonoides/farmacologia , Histona Desmetilases com o Domínio Jumonji/antagonistas & inibidores , Modelos Moleculares , Biocatálise , Humanos , Histona Desmetilases com o Domínio Jumonji/química , Histona Desmetilases com o Domínio Jumonji/metabolismo , Ácidos Cetoglutáricos/química , Ligantes , Simulação de Acoplamento Molecular , Termodinâmica
11.
AAPS PharmSciTech ; 17(2): 436-45, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26208439

RESUMO

The aim of the present study was to develop and evaluate a thermoresponsive depot system comprising of docetaxel-loaded cubosomes. The cubosomes were dispersed within a thermoreversible gelling system for controlled drug delivery. The cubosome dispersion was prepared by dilution method, followed by homogenization using glyceryl monooleate, ethanol and Pluronic® F127 in distilled water. The cubosome dispersion was then incorporated into a gelling system prepared with Pluronic® F127 and Pluronic® F68 in various ratios to formulate a thermoresponsive depot system. The thermoresponsive depot formulations undergo a thermoreversible gelation process i.e., they exists as free flowing liquids at room temperature, and transforms into gels at higher temperatures e.g., body temperature, to form a stable depot in aqueous environment. The mean particle size of the cubosomes in the dispersion prepared with Pluronic® F127, with and without the drug was found to be 170 and 280 nm, respectively. The prepared thermoresponsive depot system was evaluated by assessing various parameters like time for gelation, injectability, gel erosion, and in-vitro drug release. The drug-release studies of the cubosome dispersion before incorporation into the gelling system revealed that a majority (∼97%) of the drug was released within 12 h. This formulation also showed a short lag time (∼3 min). However, when incorporated into a thermoresponsive depot system, the formulation exhibited an initial burst release of ∼21%, and released only ∼39% drug over a period of 12 h, thus indicating its potential as a controlled drug delivery system.


Assuntos
Preparações de Ação Retardada/química , Nanoestruturas/química , Taxoides/química , Química Farmacêutica/métodos , Docetaxel , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Excipientes/química , Géis/química , Tamanho da Partícula , Poloxâmero/química , Temperatura
12.
Indian J Exp Biol ; 53(8): 489-507, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26349312

RESUMO

Cancer is a complex disease characterized by a loss in the normal cell regulatory mechanisms that govern cell survival, proliferation, and differentiation. Current chemotherapeutics, as anticancer agents, are developing resistance to single drug and also to treatment therapies involving multiple drugs. Cross resistance associated with the specificity and selectivity of existing drugs has restricted the application of chemotherapy. Alternatively, these limitations have given better insight in understanding the underlying molecular mechanisms responsible for the development of various stages in cancer. In the light of this, continuous efforts are being made in order to identify and validate newer anticancer targets. This review presents some of the important targets that have been already reported, such as aromatase, farnesyl transferase, histone deacetylase, tyrosine kinase and cyclin-dependent kinase. A few molecules designed against these targets have successfully reached clinical trials. However, only limited marketed drugs are available from these classes. Besides, the review also highlights some of the other important targets and strategies that have also drawn considerable attention in the area of anticancer drug development such as, cancer stem cells and monoclonal antibodies. Further, the integration of the tools in molecular biology with the results from preclinical and clinical trials would strengthen the effectiveness of treatment regimens in cancer patients. There lies a much scope for designing promising lead compounds and treatment therapies against these established targets.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/genética , Aromatase/genética , Aromatase/uso terapêutico , Farnesil-Difosfato Farnesiltransferase/genética , Farnesil-Difosfato Farnesiltransferase/uso terapêutico , Histona Desacetilases/genética , Histona Desacetilases/uso terapêutico , Humanos , Neoplasias/patologia , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/uso terapêutico
13.
Chem Biol Interact ; 233: 81-94, 2015 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-25824412

RESUMO

The potential of cinnamic acid as an anti-inflammatory and anti-cancer agent has been studied previously. In our investigation, novel bio-isosters of cinnamyl sulfonamide hydroxamate were synthesized, characterized and confirmed for their structure and evaluated for cytotoxicity. Three NCEs namely, NMJ-1, -2 and -3 showed cell-growth inhibition in 6 human cancer cell lines with IC50 at the range of 3.3±0.15-44.9±2.6 µM. The hydroxamate derivatives of cinnamyl sulfonamide are reported inhibitors of HDAC enzyme. Thus, the effectiveness of these molecules was determined by whole cell HDAC assay in HCT 116 cell line. NMJ-2 (0.41±0.01 µM) exhibited better enzyme inhibition (IC50) compared to SAHA (2.63±0.07). In order to evaluate induction of apoptosis by treatment, Hoechst 33342 and AO/EB nuclear staining methods were used. Further, cell cycle analysis, Annexin V binding and caspase 3/7 activation assays were performed by flow cytometry where NMJ-2 significantly arrested the cell cycle at G2/M phase, increased Annexin V binding to the cell surface and activation of caspase-3/7. Bax/Bcl-2 ratio was observed by Western blot and showed an increase with NMJ-2 treatment. This was comparable to standard SAHA. The acute toxicity study (OECD-425) showed that NMJ-2 was safe up to 2000 mg/kg in rats. 1,2-Dimethyl hydrazine (DMH) was used to produce experimental colon adenocarcinoma in Wistar rats. 5-FU and NMJ-2 (100 mg/kg p.o. and 10 mg/kg i.p. once daily for 21 days, respectively) were administered to the respective groups. Both treatments significantly reduced ACFs, adenocarcinoma count, TNF-α, IL-6, nitrite and nitrate levels in colonic tissue. Our findings indicate that NMJ-2 has potent anti-cancer activity against colon cancer, by acting through HDAC enzyme inhibition and activation of intrinsic mitochondrial apoptotic pathway, with additional anti-inflammatory activity.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Cinamatos/uso terapêutico , Colo/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Inibidores de Histona Desacetilases/uso terapêutico , Ácidos Hidroxâmicos/uso terapêutico , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Cinamatos/química , Colo/metabolismo , Colo/patologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Feminino , Inibidores de Histona Desacetilases/química , Histona Desacetilases/metabolismo , Humanos , Ácidos Hidroxâmicos/química , Modelos Moleculares , Ratos Wistar , Sulfonamidas/química , Sulfonamidas/uso terapêutico
14.
ScientificWorldJournal ; 2014: 854267, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25548795

RESUMO

Benzopyrones are proven antidiabetic drug candidate in diabetic drug discovery. In this view novel synthetic benzopyrone analogues were selected for testing in experimental diabetes. Type 2 diabetes (T2D) was induced in Wistar rats by streptozotocin (60 mg/kg, i.p.) followed by nicotinamide (120 mg/kg i.p.). Rats having fasting blood glucose (FBG)>200 mg/dL, 7 days after T2D-induction, are selected for the study. Test compounds and standard treatment were continued for 15 days. FBG, oral glucose tolerance test (OGTT), and insulin tolerance test (ITT) were determined on 21st day after induction of T2D. Plasma lipids and serum insulin were estimated. Homeostatic model assessment (HOMA-IR) was then calculated from serum insulin. Rats were sacrificed and pancreas was isolated for histopathological observations. Oxidative stress markers were estimated in liver homogenate. Quercetin, a natural product with benzopyrone ring, showed significant hypoglycemic activity comparable to glibenclamide. Treatment with test compounds lowered the FBG and insulin resistance was significant alleviated as determined by OGTT, HOMA-IR, and ITT. There was significant normalisation of liver antioxidant enzymes compared to diabetic rats indicating that all the synthesised benzopyrone analogues are beneficial in reducing oxidative stress and are on par with the standard quercetin and glibenclamide in experimental T2D.


Assuntos
Cumarínicos/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Animais , Biomarcadores/metabolismo , Glicemia/metabolismo , Cumarínicos/química , Cumarínicos/farmacologia , Creatinina/sangue , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Jejum/sangue , Teste de Tolerância a Glucose , Produtos Finais de Glicação Avançada/sangue , Glicogênio/metabolismo , Hiperglicemia/complicações , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Insulina/sangue , Resistência à Insulina , Lipídeos/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Niacinamida , Estresse Oxidativo/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Ratos Wistar , Estreptozocina
15.
Biomed Res Int ; 2014: 569130, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24995310

RESUMO

The aim of the present study was to evaluate the antitumor potential of iminoflavones in in vitro and in vivo anticancer models. Preliminary screening in various cancer cell lines revealed four potential iminoflavones out of which IMF-8 was taken based on its activity against colon cancer cells. This was further confirmed by observing the nuclear changes in the cells by AO/EB and Hoechst 33342 staining studies. In vivo activity was assessed by dimethyl hydrazine-(DMH-) induced colon cancer model in rats. Animals were administered DMH (20 mg/kg, b.w. for 10 weeks and 30 mg/kg b.w., i.p. for 10 weeks) and were supplemented with (IMF-8) iminoflavone-8 (200 mg/kg, p.o. for 14 days). Results showed that DMH induced 100% aberrant crypt foci (ACF) and polyps which were significantly reduced in the IMF-8 treated group. IMF-8 significantly increased the catalase and GSH levels whereas it reduced the TNF- α and IL-6 levels markedly which suggests the antioxidative and anti-inflammatory actions of flavonoids present in IMF-8. The histopathological images of the IMF-8 treated colon showed no signs of mucosal crypt abscess. These findings suggest that the semi-synthetic iminoflavones, IMF-8, effectively inhibit DMH-induced ACFs and colonic crypts by alleviating the oxidative stress and suppressing the inflammation.


Assuntos
Focos de Criptas Aberrantes/tratamento farmacológico , Neoplasias do Colo/tratamento farmacológico , Flavonas/administração & dosagem , 1,2-Dimetilidrazina/toxicidade , Focos de Criptas Aberrantes/induzido quimicamente , Focos de Criptas Aberrantes/patologia , Animais , Linhagem Celular Tumoral , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-6/biossíntese , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos , Fator de Necrose Tumoral alfa/biossíntese
16.
EXCLI J ; 13: 1055-74, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26417321

RESUMO

Synthetic 3-hydroxyflavone analogues (JY-1, JY-2, JY-3, JY-4), were tested for antidiabetic activity in high-fructose-diet-fed (66 %, for 6 weeks) insulin-resistant Wistar rats (FD-fed rats). The fasting blood glucose, insulin, creatinine and AGEs were decreased to near normal upon treatment with test compounds. Insulin resistance markers such as HOMA-IR, K-ITT, plasma triglycerides, lipids, endogenous antioxidant defense and glycogen were restored in FD-fed rats after treatment with 3-hydroxyflavones. It is known that insulin resistance is partly because of oxidative stress and hence antioxidant activity was determined. They exhibited significant in vitro DPPH and ABTS radical scavenging activity (IC50: 10.66-66.63 µM). Test compounds inhibited ROS and NO production in RAW 264.7 cells (IC50: 10.39-42.63 µM) and they were found as potent as quercetin. Further, the test compounds inhibited lipid peroxidation at low concentrations (IC50: 99.61-217.47 µM). All test compounds at concentrations 100-200 µM protected calf thymus DNA-damage by Fenton reaction. In addition, test compounds inhibited protein glycation in different in vitro antiglycation assays. JY-2 showed maximum potency in all the stages of glycation which was comparable to the standard quercetin and aminoguanidine. Test compounds also enhanced the glucose uptake by L6 myotubes at an EC50 much lower than that of quercetin. Thus the synthetic 3-hydroxyflavones were found to have good antidiabetic activity by pleotropic and multimodal suppression of insulin resistance and enhancement of glucose uptake by skeletal muscles. These compounds are non-toxic at the doses tested. Further, the combined antioxidant and antiglycation activities of these molecules have complementary benefits in management of diabetes.

17.
Mol Cell Biochem ; 388(1-2): 203-10, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24347174

RESUMO

Emerging data indicate that gut-derived endotoxin (metabolic endotoxemia) may contribute to low-grade systemic inflammation in insulin-resistant states. Specific gut bacteria seem to serve as lipopolysaccharide (LPS) sources and several reports claim a role for increased intestinal permeability in the genesis of metabolic disorders. Therefore, we investigated the serum levels of LPS and zonulin (ZO-1, a marker of gut permeability) along with systemic levels of tumor necrosis factor-α (TNF-α) and Interleukin-6 (IL-6) in patients with type 2 diabetes mellitus (T2DM) compared to control subjects. Study subjects were recruited from the Chennai Urban Rural Epidemiology Study [CURES], Chennai, India. Study group (n = 45 each) comprised of a) subjects with normal glucose tolerance (NGT) and (b) patients with T2DM. LPS, ZO-1, TNF-α, and IL-6 levels were measured by ELISA. Serum levels of LPS [p < 0.05], LPS activity [p < 0.001], ZO-1 [p < 0.001], TNFα [p < 0.001], and IL-6 [p < 0.001] were significantly increased in patients with T2DM compared to control subjects. Pearson correlation analysis revealed that LPS activity was significantly and positively correlated with ZO-1, fasting plasma glucose, 2 h post glucose, HbA1c, serum triglycerides, TNF-α, IL-6, and negatively correlated with HDL cholesterol. Regression analysis showed that increased LPS levels were significantly associated with type 2 diabetes [odds ratio (OR) 13.43, 95 % CI 1.998-18.9; p = 0.003]. In Asian Indians who are considered highly insulin resistant, the circulatory LPS levels, LPS activity, and ZO-1 were significantly increased in patients with type 2 diabetes and showed positive correlation with inflammatory markers and poor glycemic/lipid control.


Assuntos
Biomarcadores/sangue , Diabetes Mellitus Tipo 2/sangue , Inflamação/sangue , Lipopolissacarídeos/sangue , Proteína da Zônula de Oclusão-1/sangue , Glicemia , HDL-Colesterol/sangue , Endotoxemia/sangue , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Resistência à Insulina , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue , Fator de Necrose Tumoral alfa/sangue
19.
J Postgrad Med ; 59(1): 4-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23525051

RESUMO

CONTEXT: No single factor can predict the occurrence of post total thyroidectomy (TT) hypocalcemia. AIMS: This study was conducted to look at various factors usually implicated in post TT clinically significant hypocalcemia (CSH) and to develop a scoring system using a combination of these factors to predict CSH. SETTINGS AND DESIGN: Prospective study, tertiary care center. MATERIALS AND METHODS: 145 patients, who underwent total thyroidectomy for benign goiters and early carcinoma thyroid ( < T2/N0/M0), were included. Age of the patient, presence, or absence of hyperthyroidism, pre-operative levels of serum calcium and 25 OH vitamin D, post-operative iPTH at 8 hours and calcium at 12 hours, intra-operative parathyroid preservation status, and nodule size were studied. CSH prediction score (0 to 8) was designed based on these 8 factors. STATISTICAL ANALYSIS: SPSS 13 software was used. For comparison between groups' independent samples T-test and Chi-square test was used. Statistical significance was set at P<0.05. A logistic regression analysis model was built to assess the significant predictors. RESULTS: There were 22 males and 123 females. 64.82% had euthyroid multinodular goiters, 24.82% had toxic MNG, and 10.34% had an early carcinoma of thyroid. 30.34% developed CSH. CSH was observed in patients with low pre-operative calcium (P=0.008), low 25 OH vitamin D (P=0.001), low post-operative iPTH at 8 hours (P=0.001), low serum calcium at 12 hours after surgery (P=0.001) and lesser number of parathyroid identification at surgery (P=0.001). Patient age (P=0.2) and nodule size (P - 0.17) was not significant. Hypocalcemia risk score of > 3 had 91% sensitivity, 84% specificity with a PPV of 71% and NPV of 95%, whereas score of ≥ 4 had 100% specificity and PPV in predicting CSH. CONCLUSIONS: CSH after TT is multi-factorial, and a combination of factors (Hypocalcemia prediction score > 3) can be used to predict it so as to discharge patients within 24 hours after surgery.


Assuntos
Bócio/cirurgia , Hipocalcemia/sangue , Hipocalcemia/etiologia , Hormônio Paratireóideo/sangue , Tireoidectomia/efeitos adversos , Adulto , Idoso , Calcifediol/sangue , Cálcio/sangue , Feminino , Humanos , Hipocalcemia/diagnóstico , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Alta do Paciente , Complicações Pós-Operatórias , Período Pós-Operatório , Valor Preditivo dos Testes , Estudos Prospectivos , Medição de Risco
20.
Hepatology ; 57(3): 1238-49, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23080298

RESUMO

UNLABELLED: Toll-like receptors (TLRs) function as key regulators of liver fibrosis and are able to modulate the fibrogenic actions of nonparenchymal liver cells. The fibrogenic signaling events downstream of TLRs on Kupffer cells (KCs) and hepatic stellate cells (HSCs) are poorly defined. Here, we describe the MAP3K tumor progression locus 2 (Tpl2) as being important for the activation of extracellular regulated kinase (ERK) signaling in KCs and HSCs responding to stimulation of TLR4 and TLR9. KCs lacking Tpl2 display defects with TLR induction of cytokines interleukin (IL)-1ß, IL-10, and IL-23. tpl2(-/-) HSCs were unable to increase expression of fibrogenic genes IL-1ß and tissue inhibitor of metalloproteinase 1 (TIMP-1), with the latter being the result of defective stimulation of TIMP-1 promoter activity by TLRs. To determine the in vivo relevance of Tpl2 signaling in liver fibrosis, we compared the fibrogenic responses of wild-type (WT) and tpl2(-/-) mice in three distinct models of chronic liver injury. In the carbon tetrachloride and methionine-choline-deficient diet models, we observed a significant reduction in fibrosis in mice lacking Tpl2, compared to WT controls. However, in the bile duct ligation model, there was no effect of tpl2 deletion, which may reflect a lesser role for HSCs in wounding response to biliary injury. CONCLUSION: We conclude that Tpl2 is an important signal transducer for TLR activation of gene expression in KCs and HSCs by the ERK pathway and that suppression of its catalytic activity may be a route toward suppressing fibrosis caused by hepatocellular injuries. (HEPATOLOGY 2013).


Assuntos
Células Estreladas do Fígado/fisiologia , Cirrose Hepática/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Proteínas Proto-Oncogênicas/metabolismo , Inibidor Tecidual de Metaloproteinase-1/genética , Animais , Células Cultivadas , Citocinas/metabolismo , Células Estreladas do Fígado/citologia , Hepatócitos/citologia , Hepatócitos/fisiologia , Células de Kupffer/citologia , Células de Kupffer/fisiologia , Cirrose Hepática/genética , Cirrose Hepática/patologia , MAP Quinase Quinase Quinases/genética , Macrófagos/citologia , Macrófagos/fisiologia , Masculino , Camundongos , Camundongos Knockout , Proteínas Proto-Oncogênicas/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Receptor 4 Toll-Like/metabolismo , Receptor Toll-Like 9/metabolismo , Transcrição Gênica/fisiologia
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