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1.
Drug Chem Toxicol ; 45(5): 1986-1994, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33685313

RESUMO

Gokshuradi guggulu is an important classical polyherbal formulation used in Ayurvedic system of medicine for the treatment of various chronic diseases like kidney stones and diabetes. However, no scientific attempts were made to evaluate its oral toxicity. Hence, the present study evaluated the acute and 28 days repeated dose sub-acute oral toxicities of gokshuradi guggulu in rats. Gokshuradi guggulu was tested for its compliance using physicochemical and analytical parameters as per standards prescribed in Ayurvedic Pharmacopeia of India. In acute oral toxicity study, Wistar rats were orally administered a single dose of gokshuradi guggulu (2700 mg/kg) and clinical signs and mortality or moribund stage were observed for 14 days along with weekly body weight. On day 15, the rats were euthanized and the gross morphology was carried out during necropsy. In sub-acute (repeated dose) oral toxicity study, the rats were orally administered gokshuradi guggulu (270, 1350 and 2700 mg/kg) once daily up to 28 days. Clinical signs and mortality or moribund stage, weekly body weight, weekly feed and water consumptions, biochemical and hematological investigations, urine analysis, and major organ weights and histopathology were carried out. In acute and sub-acute toxicity studies, gokshuradi guggulu administration did not show any alteration in parameters or any adverse effect as compared to vehicle treated group. There was no mortality or moribund state observed in any group in both studies. Administration of gokshuradi guggulu in acute and 28 days repeated doses did not exhibit any toxicity or adverse effect at the doses used and NOAEL was found to be 2700 mg/kg.


Assuntos
Extratos Vegetais , Animais , Peso Corporal , Commiphora , Nível de Efeito Adverso não Observado , Extratos Vegetais/toxicidade , Gomas Vegetais , Ratos , Ratos Wistar , Testes de Toxicidade Aguda
2.
Pharm Biol ; 55(1): 53-62, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27600166

RESUMO

CONTEXT: The tuber of Amorphophallus paeoniifolius (Dennst.) Nicolson (Araceae), commonly called Suran or Jimmikand, has high medicinal value and is used ethnomedicinally for the treatment of different gastrointestinal and inflammatory disorders. OBJECTIVE: The present study evaluated the effects of extracts of Amorphophallus paeoniifolius tubers on acetic acid-induced ulcerative colitis (UC) in rats. MATERIALS AND METHODS: Wistar rats were orally administered methanol extract (APME) or aqueous extract (APAE) (250 and 500 mg/kg) or standard drug, prednisolone (PRDS) (4 mg/kg) for 7 days. On 6th day of treatment, UC was induced by transrectal instillation of 4% acetic acid (AA) and after 48 h colitis was assessed by measuring colitis parameters, biochemical estimations and histology of colon. RESULTS: APME or APAE pretreatment significantly (p < .05-.001) prevented AA-induced reduction in body weight and increase in colitis parameters viz. stool consistency, colon weight/length ratio and ulcer score, area and index. Extracts treatment attenuated (p < .001) increase in alkaline phosphatase and lactate dehydrogenase in serum and myeloperoxidase activity and cytokines in colon tissue due to AA administration. Extracts treatment prevented AA-induced elevation in lipid peroxidation and decline in activities of superoxide dismutase and catalase and reduced-glutathione content (p < .05-.001) along with histopathological alterations. PRDS also showed similar ameliorative effect on colitis. DISCUSSION AND CONCLUSION: APME and APAE showed a preventive effect on UC, and ameliorated inflammation and oxidative damage in colon. The effects may be attributed to presence of phytochemicals, betulinic acid, ß-sitosterol, and glucomannan. In conclusion, the tuber of Amorphophallus paeoniifolius exhibited an anticolitic effect through anti-inflammatory and antioxidant action.


Assuntos
Amorphophallus/química , Anti-Inflamatórios/farmacologia , Colite Ulcerativa/prevenção & controle , Colo/efeitos dos fármacos , Fármacos Gastrointestinais/farmacologia , Extratos Vegetais/farmacologia , Ácido Acético , Fosfatase Alcalina/sangue , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/toxicidade , Biomarcadores/sangue , Catalase/metabolismo , Colite Ulcerativa/sangue , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/patologia , Colo/metabolismo , Colo/patologia , Citocinas/metabolismo , Citoproteção , Modelos Animais de Doenças , Fármacos Gastrointestinais/isolamento & purificação , Fármacos Gastrointestinais/toxicidade , Glutationa/metabolismo , Mediadores da Inflamação/metabolismo , L-Lactato Desidrogenase/sangue , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/metabolismo , Fitoterapia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Tubérculos , Plantas Medicinais , Prednisolona/farmacologia , Ratos Wistar , Solventes/química , Superóxido Dismutase/metabolismo
3.
Toxicol Res (Camb) ; 11(1): 32-41, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35237409

RESUMO

Laghu vishagarbha taila (LVT) is a medicated oil preparation used in the Ayurvedic system of medicine and applied topically for the treatment of painful musculoskeletal and inflammatory disorders. It contains some mildly poisonous phytoconstituents which may show untoward effects upon application. The present study evaluated the toxicity of LVT in the acute, subacute, and subchronic dermal toxicity study in Wistar rats. LVT was tested for its compliance using physicochemical and analytical parameters as per standard methods prescribed in Ayurvedic Pharmacopoeia of India, while acute, subacute, and subchronic toxicity studies were carried out as per OECD 402, 410, and 411 guidelines, respectively. In the acute dermal toxicity study, a single dose of LVT (2000 mg/kg) was applied topically to rats, while in subacute and subchronic dermal toxicity study, the rats were topically applied LVT (1000 mg/kg) up to 28 and 90 days, respectively. LVT did not cause any alterations in clinical signs and no mortality or moribund stage was observed. The change in weekly body weight was insignificant compared with the vehicle control group. In subacute and subchronic dermal toxicity study, there were no significant changes in behavior, body weight, feed consumption, biochemical and hematological parameters, organ weight, and histological parameters compared with vehicle control rats. Topical application of single and repeated doses of LVT in rats did not exhibit adverse effects and suggests that the LD50 of LVT is more than 2000 mg/kg in the acute dose and NOAEL is more than 1000 mg/kg/day in repeated dose application.

4.
Phytomed Plus ; 1(3): 100095, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35399824

RESUMO

Background: Since December 2019, SARS-CoV-2 had been a significant threat globally, which has accounted for about two million deaths. Several types of research are undergoing and have reported the significant role of repurposing existing drugs and natural lead in the treatment of COVID-19. The plant Phyllanthus emblica (Synonym-Emblica officinalis) (Euphorbiaceae) is a rich source of vitamin C, and its use as an antiviral agent has been well established. Purpose: The present study was undertaken to investigate the potency of the several components of Phyllanthus emblica against three protein targets of 2019-nCoV viz. NSP15 endoribonuclease, main protease, and receptor binding domain of prefusion spike protein using molecular docking and dynamics studies. Methods: The docking simulation studies were carried out using Schrödinger maestro 2018-1 MM share version, while dynamics studies were conducted to understand the binding mechanism and the complexes' stability studies. Results: Out of sixty-six tested compounds, Chlorogenic acid, Quercitrin, and Myricetin were most effective in showing the highest binding energy against selected protein targets of SARS-CoV-2. The network pharmacology analysis study confirmed these compounds' role in modulating the immune response, inflammatory cascade, and cytokine storm through different signaling pathways. Conclusion: Current pharmacoinformatic approach shows possible role of Phyllanthus emblica in the treatment and management of COVID-19.

5.
RSC Adv ; 11(9): 5065-5079, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35424441

RESUMO

The present study aimed to investigate the binding affinity of andrographolide and its derivative i.e., 14-deoxy-11,12-didehydroandrographolide with targets related to COVID-19 and their probable role in regulating multiple pathways in COVID-19 infection. SMILES of both compounds were retrieved from the PubChem database and predicted for probably regulated proteins. The predicted proteins were queried in STRING to evaluate the protein-protein interaction, and modulated pathways were identified concerning the KEGG database. Drug-likeness and ADMET profile of each compound was evaluated using MolSoft and admetSAR 2.0, respectively. Molecular docking was carried using Autodock 4.0. Andrographolide and its derivative were predicted to have a high binding affinity with papain-like protease, coronavirus main proteinase, and spike protein. Molecular dynamics simulation studies were performed for each complex which suggested the strong binding affinities of both compounds with targets. Network pharmacology analysis revealed that both compounds modulated the immune system by regulating chemokine signaling, Rap1 signaling, cytokine-cytokine receptor interaction, MAPK signaling, NF-kappa B signaling, RAS signaling, p53 signaling, HIF-1 signaling, and natural killer cell-mediated cytotoxicity. The study suggests strong interaction of andrographolide and 14-deoxy-11,12-didehydroandrographolide against COVID-19 associated target proteins and exhibited different immunoregulatory pathways.

6.
Heliyon ; 6(5): e04023, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32509986

RESUMO

The tubers of Amorphophallus paeoniifolius (Elephant foot yam), principally consumed as crop food and vegetables, are used in ethno-medicinal practices in mitigation of constipation and piles. Hence, present study evaluated the effect of tubers of A. paeoniifolius and its active constituents glucomannan and betulinic acid on experimentally-induced constipation. The tuber and its extracts were standardized as per Ayurvedic Pharmacopoeia of India and physicochemical constants were found within the pharmacopoeial limit. HPTLC fingerprint profile of extracts has been developed using suitable mobile phase. Methanolic extract was subjected to column chromatography. The isolated phytoconstituents were characterized by FT-IR, NMR and MS and identified as betulinic acid and ß-sitosterol. Functional constipation was induced in rats by oral administration of loperamide (3 mg/kg) for first 3 consecutive days. The rats were orally treated with methanolic and aqueous tuber extracts in the doses of 125, 250 and 500 mg/kg, glucomannan (300 mg/kg) and betulinic acid (1.5 mg/kg) for 7 days. The parameters viz. number of stools, wet weight of stools and moisture content of stools and intestinal transit were studied. Treatment with tuber extracts, glucomannan and betulinic acid showed significant (p < 0.05) increase in fecal parameters and intestinal transit in constipated rats. The effects were comparable to standard laxative drug, sodium picosulfate (5 mg/kg, orally). The results indicated that tuber extracts and its active constituents showed laxative effect and relieved constipation. It is concluded that tuber of A. paeoniifolius exhibited beneficial effect in functional constipation possibly through its laxative action. The study validates its ethno-medicinal use in correction of constipation. The principal constituents, betulinic acid and glucomannan in tuber extracts might have played important role in relieving the constipation.

7.
J Ethnopharmacol ; 195: 275-282, 2017 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-27864113

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The leaves of Chenopodium album Linn. are traditionally used for correction of kidney diseases and urinary stones. The present work investigated the effect of methanolic and aqueous extracts of leaves of Chenopodium album on experimentally-induced urolithiasis in rats to substantiate its traditional use as antilithiatic agent. MATERIALS AND METHODS: The leaf extract was standardized by HPLC. Urolithiasis was induced in rats by administration of 0.75% v/v of ethylene glycol (EG) in distilled water and in addition, vehicle or methanol (CAME) or aqueous (CAAE) extract of the leaves of Chenopodium album each in the dose 100, 200 and 400mg/kg or Cystone (750mg/kg) were administered daily orally for 28 days. Urolithiasis was assessed by estimating the calcium, phosphorus, urea, uric acid, and creatinine in both urine and plasma. The volume, pH and oxalate levels were also estimated in urine. The renal oxalate content was estimated in kidney while calcium oxalate deposits were observed histologically. RESULTS: The treatment with CAME or CAAE for 28 days significantly attenuated the EG-induced elevations in the urine and plasma levels of calcium, phosphorus, urea, uric acid and creatinine along with decrease in urine volume, pH and oxalates. The treatments also decreased renal tissue oxalate and deposition of oxalate crystals in kidney due to EG treatment. The effects of CAME and CAAE were comparable to standard antilithiatic agent, cystone. The findings indicate the preventive effect of CAME and CAAE which can be due to inhibitory effect on crystallization and stone dissolution. The effect was attributed to the presence of phytochemicals like flavonoids and saponins. CONCLUSION: In conclusion, Chenopodium album leaves exhibited antilithiatic effect and validates its ethnomedicinal use in urinary disorders and kidney stones.


Assuntos
Chenopodium album/química , Etilenoglicol , Rim/efeitos dos fármacos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Urolitíase/prevenção & controle , Agentes Urológicos/farmacologia , Animais , Biomarcadores/sangue , Biomarcadores/urina , Cromatografia Líquida de Alta Pressão , Cristalização , Modelos Animais de Doenças , Feminino , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Rim/metabolismo , Rim/fisiopatologia , Masculino , Metanol/química , Fitoterapia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Plantas Medicinais , Ratos Wistar , Saponinas/isolamento & purificação , Saponinas/farmacologia , Solventes/química , Fatores de Tempo , Micção/efeitos dos fármacos , Urolitíase/sangue , Urolitíase/induzido quimicamente , Urolitíase/urina , Agentes Urológicos/isolamento & purificação , Agentes Urológicos/toxicidade , Água/química
8.
Anc Sci Life ; 36(2): 90-97, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28446830

RESUMO

BACKGROUND: Bryophyllum pinnatum, commonly known as Pattharcatta, is used traditionally in ethnomedicinal practices for the treatment of kidney stone and urinary insufficiency. AIM: The present study evaluated the effect of Bryophyllum pinnatum on ethylene glycol (EG)-induced renal calculi in rats. MATERIALS AND METHODS: Renal calculi were induced in rats by administration of 0.75% EG in drinking water and co-treated orally with standard drug, Cystone (750 mg/kg), or alcoholic and hydro-alcoholic extracts in doses of 100, 200 and 400 mg/kg for 28 days. Weekly body weights were recorded. On day 29, urolithiasis was confirmed by assessing the urinary parameters (urine volume, pH, uric acid, calcium, phosphorus, oxalate, magnesium and creatinine clearance), serum biochemical parameters (creatinine, uric acid, urea, calcium, phosphorus and magnesium), oxidative stress parameters and histology of kidney. RESULTS: Treatment with extracts attenuated the EG-induced decrease in body weight and elevation in urinary parameters (uric acid, calcium, phosphorus and oxalate) and serum biochemical parameters (creatinine, uric acid, urea, calcium, phosphorus and magnesium). Extract treatment also reversed EG-induced decrease in urine volume, pH, magnesium and creatinine clearance, oxidative and histological damages in kidneys. Results were comparable to standard drug, Cystone. Results indicated that EG administration caused renal calculi formation which is prevented by treatment with extracts. The observed antilithiatic effect may be attributed to the presence of high content of phenolics, flavonoids and saponins in the extracts. CONCLUSION: Bryophyllum pinnatum leaves showed preventive effect against renal calculi formation and validates its ethnomedicinal use in urinary disorders. It further supports its therapeutic potential for the treatment of urinary calculi.

9.
J Ayurveda Integr Med ; 7(3): 144-150, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27665674

RESUMO

BACKGROUND: Chandraprabha vati is a classical Ayurvedic formulation, markedly used for mitigation of Prameha, which correlates in many ways with obesity, metabolic syndrome and diabetes mellitus. OBJECTIVE: The present study was aimed to investigate effect of Chandraprabha vati in experimentally-induced hyperglycemia and lipid profile alterations. MATERIALS AND METHODS: Antidiabetic effect of Chandraprabha vati was studied in fifty five Wistar rats. Graded doses of Chandraprabha vati (50, 100 and 200 mg/kg) were administered orally for 7 days to normal and alloxan-hyperglycemic rats (65 mg/kg, intravenously), and to glucose loaded normal rats for oral glucose tolerance test (OGTT). Fasting plasma glucose levels were assessed on different time intervals along with plasma cholesterol and triglycerides. Metformin (500 mg/kg, orally) was used as standard drug. RESULTS: Chandraprabha vati did not cause any significant reduction in plasma glucose levels of normal rats (p > 0.05) but normalized the impaired glucose tolerance at 60 and 120 min (p < 0.05-p < 0.001) in OGTT when compared to vehicle control. In alloxan-hyperglycemic rats, administration of Chandraprabha vati (200 mg/kg) significantly reduced plasma glucose at 3 h, 12 h, 3rd day and 7th day (p < 0.01-p < 0.001) along with reduction in cholesterol and triglycerides levels (p < 0.01-p < 0.001) when compared to diabetic control group. The effects were comparable with metformin. CONCLUSIONS: Chandraprabha vati exhibited anti-hyperglycemic effect and attenuated alterations in lipid profile. The results support the use of Chandraprabha vati for correction of Prameha in clinical practice.

10.
J Ethnopharmacol ; 192: 183-191, 2016 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-27426509

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Amorphophallus paeoniifolius (Dennst.) Nicolson (Family- Araceae) is a crop of south East Asian origin. In India, its tuber is widely used in ethnomedicinal practices by different tribes for the treatment of piles (hemorrhoids). AIM: The present study evaluated the effect of methanolic and aqueous extract of Amorphophallus paeoniifolius tuber on croton oil induced hemorrhoids in rats. MATERIALS AND METHODS: The methanolic extract was standardized with the major phenolic compound, betulinic acid, by HPLC. The hemorrhoids were induced by applying 6% croton oil preparation in the ano-rectal region. Rats were orally administered methanolic and aqueous extract at doses of 250 and 500mg/kg, each for 7 days. Pilex (200mg/kg) was used as reference anti-hemorrhoidal drug. Hemorrhoids were assessed on eighth day by measuring hemorrhoidal and biochemical parameters along with histology of ano-rectal tissue. RESULTS: Croton oil application caused induction of hemorrhoids as indicated by significant (p<0.001) increase in plasma exudation of Evans blue in ano-rectal tissue, macroscopic severity score and ano-rectal coefficient as compared to normal rats. It significantly (p<0.001) elevated lactate dehydrogenase and cytokines (TNF-α and IL-6) levels in serum and increased myeloperoxidase activity and lipid peroxidation in ano-rectal tissue along with marked histological damage as compared to normal rats. Treatment with tuber extracts and pilex significantly (p<0.05-p<0.001) ameliorated Evans blue exudation, hemorrhoidal parameters and other biochemical parameters with attenuation of tissue damage compared to hemorrhoid control rats. The results indicate that tuber extracts exhibited curative action on hemorrhoids. The aqueous extract showed more pronounced effect than methanolic extract. The effects may be attributed to anti-inflammatory and antioxidant properties. CONCLUSION: Results indicate that tuber of Amorphophallus paeoniifolius exhibited curative action on hemorrhoids through anti-inflammatory and antioxidant properties. The study validates the ethnomedicinal use of tuber in hemorrhoids and implicates its therapeutic potential as an anti-hemorrhoidal agent.


Assuntos
Amorphophallus/química , Canal Anal/efeitos dos fármacos , Anti-Inflamatórios/farmacologia , Hemorroidas/tratamento farmacológico , Extratos Vegetais/farmacologia , Tubérculos/química , Reto/efeitos dos fármacos , Canal Anal/metabolismo , Canal Anal/patologia , Animais , Anti-Inflamatórios/isolamento & purificação , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Biomarcadores/sangue , Cromatografia Líquida de Alta Pressão , Óleo de Cróton , Modelos Animais de Doenças , Hemorroidas/sangue , Hemorroidas/induzido quimicamente , Hemorroidas/patologia , Mediadores da Inflamação/sangue , Interleucina-6/sangue , L-Lactato Desidrogenase/sangue , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Metanol/química , Triterpenos Pentacíclicos , Peroxidase/metabolismo , Extratos Vegetais/isolamento & purificação , Ratos Wistar , Reto/metabolismo , Reto/patologia , Indução de Remissão , Índice de Gravidade de Doença , Solventes/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Fator de Necrose Tumoral alfa/sangue , Água/química , Ácido Betulínico
12.
Anc Sci Life ; 32(3): 150-5, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24501443

RESUMO

BACKGROUND: Grewia asiatica Linn. (Family: Tiliaceae), called Phalsa in Hindi is an Indian medicinal plant used for a variety of therapeutic and nutritional uses. The root bark of the plant is traditionally used in rheumatism (painful chronic inflammatory condition). AIMS: The present study demonstrates the analgesic and anti-inflammatory activity of root bark of G. asiatica in rodents. SETTINGS AND DESIGN: The methanolic extract of Grewia asiatica (MEGA) and aqueous extract of Grewia asiatica (AEGA) of the bark were prepared and subjected to phytochemical tests and pharmacological screening for analgesic and anti-inflammatory effect in rodents. MATERIALS AND METHODS: Analgesic effect was studied using acetic acid-induced writhing in mice and hot plate analgesia in rats while anti-inflammatory activity was investigated using carrageenan-induced paw oedema in rats. The MEGA or AEGA was administered orally in doses of 200 and 400 mg/kg/day of body weight. STATISTICAL ANALYSIS: Data were analysed by one-way analysis of variance followed by Dunnett's test. RESULTS: The extracts showed a significant inhibition of writhing response and increase in hot plate reaction time and also caused a decrease in paw oedema. The effects were comparable with the standard drugs used. CONCLUSIONS: The present study indicates that root bark of G. asiatica exhibits peripheral and central analgesic effect and anti-inflammatory activity, which may be attributed to the various phytochemicals present in root bark of G. asiatica.

13.
Asian Pac J Trop Med ; 5(5): 380-4, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22546655

RESUMO

OBJECTIVE: To study the influence of methanolic and aqueous extract of Withania somnifera (W. somnifera) root on the marble-burying behavior of mice a well-accepted model of obsessive compulsive behavior. METHODS: Mice were divided in different groups (n = 6). Fluoxetine (5, 10, 15 mg/kg), (10, 25, 50, 100 mg/kg) and methanolic extract W. somnifera (MEWS) (10, 25, 50, 100 mg/kg) were administered i.p. 30 min. prior to the assessment of marble burying behavior and locomotor activity. The control group received vehicle of the extract. RESULTS: Administration of aqueous extracts W. somnifera (AEWS) and MEWS (50 mg/kg) successively decreased the marble burying behavior activity without affecting motor activity. This effect of AEWS and MEWS was comparable to standard fluoxetine, ritanserin and parachlorophenylalanine. CONCLUSIONS: W. somnifera extract is effective in treating obsessive compulsive disorder.


Assuntos
Transtorno Obsessivo-Compulsivo/tratamento farmacológico , Fitoterapia/métodos , Extratos Vegetais/farmacologia , Withania , Análise de Variância , Animais , Ansiolíticos/farmacologia , Feminino , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Raízes de Plantas , Ritanserina/farmacologia
14.
Biochem Pharmacol ; 75(8): 1670-6, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18329630

RESUMO

Herbal antidiabetic preparations are often used as an add-on therapy in diabetes and such herbal preparations often contains quercetin that can inhibit cytochrome P450 (CYP) 3A4. This enzyme is responsible for metabolizing pioglitazone, a commonly used antidiabetic agent. Hence, it was speculated that quercetin may influence the bioavailability of pioglitazone, which could be particularly crucial, as any increment in its plasma levels may raise safety concerns. Thus, we first established the inhibitory influence of quercetin (2, 10 and 20 mg/kg, p.o.) on CYP3A activity by an in vivo method of estimating levels of midazolam in female rats pretreated with dexamethasone. It was further confirmed in vitro using erythromycin-N-demethylase (EMD) assay. These studies indicated potent inhibition of CYP3A activity by quercetin (10 and 20 mg/kg, in vivo; 1 and 10 microM, in vitro). In another experiment, pioglitazone was administered orally (10 mg/kg) and intravenously (5mg/kg) to quercetin (10 mg/kg) pretreated female rats and its plasma levels were determined at various time points (0.5, 1, 2, 4, 8 and 24 h after oral administration; 0.083, 0.5, 1, 2, 8, 12 and 18 h after i.v. administration) by HPLC. Quercetin pretreatment increased AUC(0-infinity) of pioglitazone after oral administration by 75% and AUC(0-infinity) after intravenous administration by 25% suggesting decreased metabolism, which could be due to inhibition of CYP3A by quercetin. In conclusion, add-on preparations containing quercetin may increase the bioavailability of pioglitazone, and hence should be cautiously used.


Assuntos
Antioxidantes/farmacologia , Inibidores das Enzimas do Citocromo P-450 , Hipoglicemiantes/farmacocinética , Quercetina/farmacologia , Tiazolidinedionas/farmacocinética , Animais , Disponibilidade Biológica , Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450/metabolismo , Dexametasona/farmacologia , Feminino , Hipoglicemiantes/sangue , Microssomos/metabolismo , Midazolam/sangue , Midazolam/farmacocinética , Pioglitazona , Ratos , Ratos Sprague-Dawley , Tiazolidinedionas/sangue
15.
Behav Pharmacol ; 19(4): 308-16, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18622178

RESUMO

The correlation between neuronal mechanism of anxiety and neuroanatomic expression/neuromodulatory role of gonadotropin-releasing hormone (GnRH), points to a role of GnRH in the modulation of anxiety. Therefore, we investigated the influence of GnRH agonists and antagonist on the anxiety-like behavior of rats in the elevated plus-maze and social interaction tests. GnRH agonists, leuprolide [100 or 200 ng/rat, intracerebroventricularly (i.c.v.)] or 6-D-tryptophan luteinizing hormone-releasing hormone (400 ng/rat, i.c.v.), significantly increased percentage of open arms entries, time spent in open arms, and time spent in social interaction. The observed anxiolytic effect of these agents was comparable with diazepam (0.5-1.0 mg/kg, intraperitoneally). Treatment with a GnRH antagonist [pGlu-D-Phe-Trp-Ser-Tyr-D-Ala-Leu-Arg-Pro-Gly-NH2, (100 ng/rat, i.c.v.)], significantly reduced percentage of open arm indices and decreased time spent in social interaction, indicating an anxiogenic-like effect. Further, castrated rats exhibited anxiogenic-like behavior in these tests, which was significantly attenuated by leuprolide (200 ng/rat, i.c.v.) or 6-D-tryptophan luteinizing hormone-releasing hormone (400 ng/rat, i.c.v.), indicating the noninvolvement of peripheral sex hormone in their anxiolytic-like effect, at least in castrated rats. In conclusion, this study indicated a putative role of GnRH in the control of anxiety, and further adds to the importance of investigating the possible role of the hypothalamus-pituitary-gonadal axis in regulating the anxiety-related disorders arising out of hypothalamus-pituitary-adrenal axis dysregulation.


Assuntos
Ansiolíticos/farmacologia , Hormônio Liberador de Gonadotropina/agonistas , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Leuprolida/farmacologia , Aprendizagem em Labirinto/efeitos dos fármacos , Comportamento Social , Pamoato de Triptorrelina/farmacologia , Animais , Ansiedade/psicologia , Comportamento Animal/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Injeções Intraventriculares , Masculino , Orquiectomia , Sistema Hipófise-Suprarrenal/metabolismo , Ratos , Ratos Sprague-Dawley
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