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1.
ACS Omega ; 9(8): 9813-9822, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38434828

RESUMO

Diabetes, also known as diabetes mellitus (DM), is a metabolic disorder characterized by an abnormal rise in blood sugar (glucose) levels brought on by a complete or partial lack of insulin secretion along with corresponding changes in the metabolism of lipids, proteins, and carbohydrates. It has been reported that medicinal plants play a pivotal role in the treatment of various ailments such as diabetes mellitus, dyslipidemia, and hypertension. The current study involved exploring the acute toxicity and in vivo antidiabetic activity of berberine (WA1), palmatine (WA2), and 8-trichloromethyl dihydroberberine (WA3) previously isolated from Berberis glaucocarpa Stapf using a streptozotocin (STZ)-induced diabetic rat model. Body weight and blood glucose level were assessed on a day interval for 4 weeks. Biochemical parameters, antioxidant enzymes, and oxidative stress markers were also determined. In an acute toxicity profile, the WA1, WA2, and WA3 were determined to be nontoxic up to 500 mg/kg (b.w). After the second and third weeks of treatment (14 and 21 days), the blood glucose levels in the WA1-, WA2-, and WA3-treated groups were significantly lower than those in the diabetic control group (476.81 ± 8.65 mg/dL, n = 8, P < 0.001). On the 21st day, there was a decrease in the blood glucose level and the results obtained were 176.33 ± 4.69, 197.21 ± 4.80, and 161.99 ± 4.75 mg/dL (n = 8, P < 0.001) for WA1, WA2, and WA3 at 12 mg/kg, respectively, as opposed to the diabetic control group (482.87 ± 7.11 mg/dL, n = 8, P < 0.001). Upon comparison with the diabetic group at the end of the study (28 days), a substantial drop in the glucose level of WA3 at 12 mg/kg (110.56 ± 4.11 mg/dL, n = 8, P < 0.001) was observed that was almost near the values of the normal control group. The treated groups (WA1, WA2, and WA3) treated with the samples displayed a significant decline in the levels of HbA1c. Treatment of the samples dramatically lowered the lipid level profile. In groups treated with samples, plasma levels of triglycerides, total cholesterol, and LDL were significantly lowered [F (5, 42) = 100.6, n = 8, P < 0.001]; these levels were also significantly decreased [F (5, 42) = 129.6 and 91.17, n = 8, P < 0.001]. In contrast to the diabetes group, all treated groups had significantly higher HDL levels [F (5, 42) = 15.46, n = 8, P < 0.001]. As a result, hypolipidemic activity was anticipated in the samples. In addition to that, the activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) was considerably elevated in the groups treated with the sample compared to the diabetic control group (n = 8, P < 0.001).

2.
Molecules ; 27(8)2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35458597

RESUMO

Different species of Artemisia have been reported to have therapeutic potential in treating various health disorders, including diabetes and memory dysfunction. The present study was planned to evaluate the effects of Artemisia macrocephala Jacquem crude extract and its subfractions as antiamnesic agents in streptozotocin-induced (STZ) diabetic mice. The in vivo behavioral studies were performed using the Y Maze test and novel object recognition test (NORT) test at doses of 100 and 200 mg/kg of crude extract and 75 and 150 mg/kg of fractions. The in vitro and ex vivo anticholinesterase activities, along with biochemical parameters (superoxide dismutase, catalase, glutathione and lipid peroxidation) in the brain, were evaluated. Blood glucose levels were monitored with a glucometer; crude extract and fractions reduced the glucose level considerably, with some differences in the extent of their efficacies. The crude extract and fractions demonstrated significant inhibitory activity against cholinesterases (AChE and BuChE) in vitro. Crude, chloroform and ethyl acetate extract were found to be more potent than the other fractions, with IC50 of Crd-Am = 116.36 ± 1.48 and 240.52 ± 1.35 µg/mL, Chl-Am = 52.68 ± 1.09 and 57.45 ± 1.39 µg/mL and Et-Am = 75.19 ± 1.02 and 116.58 ± 1.09 µg/mL, respectively. Oxidative stress biomarkers like superoxide dismutase, catalase and glutathione levels were elevated, whereas MDA levels were reduced by crude extract and all fractions with little difference in their respective values. The Y-maze test and novel object recognition test demonstrated declines in memory impairment in groups (n = 6) treated with crude extract and fractions as compared to STZ diabetic (amnesic) group. The most active fraction, Chl-Am, was also subjected to isolation of bioactive compounds; three compounds were obtained in pure state and designated as AB-I, AB-II and AB-III. Overall, the results of the study showed that Artemisia macrocephala Jacquem enhanced the memory impairment associated with diabetes, elevated acetylcholine levels and ameliorated oxidative stress. Further studies are needed to explore the beneficial role of the secondary metabolites isolated in the present study as memory enhancers. Toxicological aspects of the extracts are also important and need to be evaluated in other animal models.


Assuntos
Artemisia , Diabetes Mellitus Experimental , Transtornos da Memória , Estresse Oxidativo , Animais , Antioxidantes/farmacologia , Artemisia/química , Encéfalo/metabolismo , Catalase/metabolismo , Diabetes Mellitus Experimental/metabolismo , Glutationa/metabolismo , Transtornos da Memória/induzido quimicamente , Camundongos , Extratos Vegetais/uso terapêutico , Estreptozocina/farmacologia , Superóxido Dismutase/metabolismo
3.
Pak J Pharm Sci ; 34(2): 577-583, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34275832

RESUMO

Chenopodium ambrosioides is abundantly available in Malakand region. As constituents and concentrations of essential oils vary based on its geographical location, we carried our current study to extract and evaluate its possible relaxant activity in rabbits' jejunum and anti-leishmanial activity against promastigotes of Leishmania tropica. The essential oil was obtained from aerial fresh parts through steam distillation followed by GC/MS analysis. Antispasmodic activity was performed on spontaneous and KCl induced contractions. Curves for calcium concentration response (CCRCs) were prepared with and without different concentrations of essential oils and verapamil - a standard calcium channel blocker as per our reported procedures. GC/MS analysis indicated that the essential oil contains 4-carene (56.59%) and o-cymene (41.46%), the two most abundant compounds previously reported from this species. The LD50 value for acute toxicity is 279.66±2.2mg/kg. The essential oil have significant antileishmanial activity with LC50 of Log10 (1.83±0.0026) ×10-6mg/ml, potent relaxant activity on rabbits' jejunal preparations with respective EC50 = 1.46±0.15mg/ml for spontaneous activity. For KCl (80mM) induced contractions, EC50=0.26±0.02mg/ml. In CCRCs, the oil produced a right shift as exhibited by verapamil. More, its relaxant activity, which is mediated through calcium channel blocking mechanism, proves a rationale for its traditional use in gut spasm.


Assuntos
Antiprotozoários/farmacologia , Chenopodium ambrosioides , Jejuno/efeitos dos fármacos , Leishmania tropica/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Óleos Voláteis/farmacologia , Parassimpatolíticos/farmacologia , Animais , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/química , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Coelhos
4.
Pak J Pharm Sci ; 34(1(Supplementary)): 197-203, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34275843

RESUMO

The current study is focused towards screening for its phytochemicals, phenolic and flavonoid contents of different species of Chenopodium. The plants were also screened for corroborating the traditional use of medicinal plants locally used for pain by determining the extract and their fractions for the in-vivo analgesic activity by using the modern scientific system. Among chloroform fractions, a high level of total phenolic contents was found in chloroform fraction of Chenopodium ambrosioides (ChAm-Chf) with 57.12±1.02 followed by Chenopodium botrys (ChBt-Chf) with 56.79±0.71. High content of flavonoids was found in chloroform fraction of Chenopodium botrys (ChBt-Chf) extract with 78.35±0.84 followed by Chenopodium ambrosioides (ChAm-Chf) with 75.20±0.81. The crude extract Chenopodium album, Chenopodium botrys and Chenopodium ambrosioides (ChAl-Crd, ChBt-Crd and ChAm-Crd) at 100 and 200 mg/kg, chloroform and ethylacetate fractions (ChAl-Chf, ChBt-Chf, ChAm-Chf, ChAl-Et, ChBt-Et and ChAm-Et) at 75 mg/kg caused significant inhibition (P<0.05, P<0.01, P<0.001, n=8) of the analgesic response induced by acetic acid, formalin and hotplate method. Mechanistically, the naloxone overturns completely the analgesic effects of beta-sitosterol (SN2) while partial reversal was observed by ursolic acid (SN1) indicating other possible mechanisms in association with opioid receptors.


Assuntos
Analgésicos/farmacologia , Comportamento Animal/efeitos dos fármacos , Chenopodium , Fenóis/farmacologia , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Animais , Chenopodium album , Chenopodium ambrosioides , Descoberta de Drogas , Flavonoides , Camundongos , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Fitoterapia , Extratos Vegetais/química , Sitosteroides/farmacologia , Triterpenos/farmacologia , Ácido Ursólico
5.
Pak J Pharm Sci ; 32(2 (Supplementary)): 817-823, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31103977

RESUMO

The beneficial effects of Pistacia integerrima (PI) fruit methanol extract on some liver and kidney related parameters and blood cells count of paracetamol (PCM) intoxicated male rabbits were studied. Paracetamol intoxication caused remarkable increase in the serum ALT, AST and ALP levels. The PCM intoxicated rabbits that received PI extract orally at doses of 200 mg and 400 mg/kg b.w. /oral/day for 16 days showed significant reduction in serum ALT, AST and ALP levels (P<0.05). Liver microsections from PCM intoxicated rabbits treated with PI fruit methanol extract showed improvement in the liver histoarchitecture. The urine output of PCM intoxicated control rabbits group was significantly lower (P<0.05). The PCM intoxicated rabbits that received PI extract showed significant increase in urine output (P<0.05). The PCM intoxicated rabbits treated with PI extract also showed significant reduction in the levels of serum urea and creatinine (P<0.05). The renal creatinine clearance of PCM rabbits treated with PI extract improved significantly (P<0.05). Microsections of kidneys from PCM intoxicated rabbits treated with PI fruit methanol extract showed improvement in renal histoarchitecture. During this study, PI extract caused no improvement in the RBC count of PCM intoxicated rabbits. However, the extract caused significant increase in WBC and platelets count (P < 0.05) of PCM intoxicated rabbits. From the findings of the present research, it was concluded that oral administration of P. integerrima fruit methanol extract is beneficial for the liver and kidney related biochemical parameters and blood cells count of paracetamol intoxicated male rabbits.


Assuntos
Acetaminofen/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Rim/efeitos dos fármacos , Pistacia/química , Extratos Vegetais/farmacologia , Acetaminofen/efeitos adversos , Animais , Contagem de Células Sanguíneas , Doença Hepática Induzida por Substâncias e Drogas/sangue , Doença Hepática Induzida por Substâncias e Drogas/patologia , Frutas , Rim/patologia , Masculino , Metanol/química , Coelhos
6.
Pak J Pharm Sci ; 32(6(Supplementary)): 2865-2871, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32024626

RESUMO

Plants belongs to Asteraceae family are reported to be rich in major phytochemical including flavonoids and are documented to acquire antidiabetic response. Antidiabetic effects of salvigenin, eupatilin and cirsilineol were screened on in-vitro enzyme inhibition and in-vivo streptozotocin animal models. Administration of salvigenin, eupatilin and cirsilineol (7.5 and 15mg/kg) produced antidiabteic responses in streptozotocin model for diabetes. All natural flavonoids reduces the blood glucose level to a significant level (*P<0.05, **P<0.01, ***P<0.001, n=8) but promising results were observed in eupatilin at dose of 7.5mk/kg (364.12±4.3 to 128.41±4.2mg/dL, n=8) and at dose of 7.5mk/kg 363.65±4.8 to 126.14±5.1mg/dL, n=8). Administration of salvigenin, eupatilin and cirsilineol (7.5 and 15mg/kg) for 28 days showed a substantial fall (*P<0.05, **P<0.01, ***P<0.001, n=8) in total cholesterol, LDL and triglcerides (TGs) in comparison to diabetic model. The isolated flavonoids reduced considerably the serum ALP, SGPT and SGOT in rats intoxicated with streptozotocin. The results indicate that the flavonoids may be useful in the development of new antidiabetic drugs.


Assuntos
Artemisia/química , Diabetes Mellitus Experimental/tratamento farmacológico , Flavonoides/farmacologia , Hipoglicemiantes/farmacologia , Animais , Diabetes Mellitus Experimental/sangue , Flavonas/isolamento & purificação , Flavonas/farmacologia , Flavonas/uso terapêutico , Flavonoides/isolamento & purificação , Flavonoides/uso terapêutico , Teste de Tolerância a Glucose , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/uso terapêutico , Lipídeos/sangue , Camundongos Endogâmicos BALB C , Estrutura Molecular , Ratos Sprague-Dawley , Estreptozocina
7.
BMC Complement Altern Med ; 16: 178, 2016 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-27296395

RESUMO

BACKGROUND: Tissue damage is associated with pain, which is an alarming sign. Aspirin and morphine have been widely used in recent decades for management of pain. Medicinal herbs have been in use for treatment of different diseases for centuries. Many of these herbs possess analgesic activity with relatively less incidences of adverse effects. The strong positive correlation of alkaloids in medicinal plants for analgesic activity persuades an intention to determine possible analgesic activity of total alkaloids extracted from the selected medicinal plants using animal models to answer its possible mechanisms. METHODS: Crude alkaloids from selected medicinal plants (Woodfordia fruticosa, Adhatoda vasica, Chenopodium ambrosioides, Vitex negundo, Peganum harmala and Broussonetia papyrifera) were extracted as per reported literature. The test crude alkaloids were screened foracute toxicity study. Writhings induced by acetic acid, tail immersion method and formalin-induced nociception assay procedures were used for possible analgesic effects of the crude alkaloids. RESULTS: Crude alkaloids were safe up to dose of 1250 mg/kg body weight in mice. The alkaloids significantly reduced the abdominal constrictions, and increased the time for paw licking response in both phases with a significant raise in latency time in nociception models (P ≤ 0.05). Moreover, the antinociceptive response was significantly attenuated by pretreatment with naloxone suggesting involvement of the opioid receptors for possible antinociceptive action. CONCLUSIONS: Crude alkaloids of Woodfordia fruticosa and Peganum harmala showed prominent analgesic potentials through inhibition of peripheral as well as central nervous system mechanisms. Further work is required for isolation of the pharmacologically active constituents.


Assuntos
Alcaloides/isolamento & purificação , Analgésicos/isolamento & purificação , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Alcaloides/farmacologia , Alcaloides/toxicidade , Analgésicos/farmacologia , Analgésicos/toxicidade , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Manejo da Dor , Extratos Vegetais/toxicidade
8.
BMC Complement Altern Med ; 13: 138, 2013 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-23773797

RESUMO

BACKGROUND: Rubus fruticosus is used in tribal medicine as anthelmintic and an antispasmodic. In the current work, we investigated the anthelmintic and antispasmodic activities of crude methanol extract of fruits of R. fruticosus on scientific grounds. Acute toxicity and brine shrimp cytotoxicity activity of the extract were also performed. METHODS: Acute toxicity study of crude methanol extract of R. fruticosus was performed on mice. In vitro Brine shrimp cytotoxicity assay was performed on shrimps of Artemia salina. In vitro Anthelmintic activity was tested against Raillietina spiralis and Ascaridia galli. Relaxant activities were tested on spontaneous rabbits' jejunal preparations. Calcium chloride curves were constructed to elucidate possible mode of action of the extract. RESULTS: LD 50 of the extract for acute toxicity studies was 887.75 ± 9.22 mg/ml. While CC 50 of the extract for Brine shrimps cytotoxicity assay was 13.28 ± 2.47 µg/ml. Test samples of crude methanolic extract of R. fruticosus (Rf.Cr) at concentration 20 mg/ml showed excellent anthelmintic activity against Raillietina spiralis. Anthelmintic activity was 1.37 times of albendazole against the Raillietina spiralis at concentration 40 mg/ml. At higher concentration (40 mg/ml), Rf.Cr has 89. 83% parasiticidal activity. The mean EC50 relaxation activity for spontaneous and KCl-induced contractions was 7.96 ± 0.1 and 6.45 ± 0.29 mg/ml, respectively. EC 50 (Log[Ca++]M) for control calcium chloride curves was -1.75 ± 0.01 vs. EC 50 -1.78 ± 0.06 in the presence of 3.0 mg/ml of Rf.Cr. Similarly, EC 50(Log[Ca++]M) in the absence and presence of verapamil (0.1 µM) were -2.46 ± 0.01 and -1.72 ± 0.02, respectively. CONCLUSIONS: The anthelmintic and relaxant activities explained traditional uses of R. fruticosus on scientific grounds. Relaxant activity follows the inhibition of voltage gated channels. Although the plant extract has cytotoxic effects, yet it is evident from acute toxicity study that it is safe in concentration 100 mg/kg. Further work is required to isolate pharmacologically active compounds.


Assuntos
Anti-Helmínticos/farmacologia , Citotoxinas/farmacologia , Frutas/química , Parassimpatolíticos/farmacologia , Extratos Vegetais/farmacologia , Rosaceae/química , Animais , Artemia/efeitos dos fármacos , Ascaridia/efeitos dos fármacos , Bioensaio , Feminino , Masculino , Camundongos , Coelhos
9.
BMC Complement Altern Med ; 12: 29, 2012 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-22463730

RESUMO

BACKGROUND: Verbascum thapsus is used in tribal medicine as an antispasmodic, anti-tubercular agent and wormicide. In this study, we investigated the antispasmodic and anthelmintic activities of crude aqueous methanolic extract of the plant. METHODS: V. thapsus extracts were tested against roundworms (Ascaridia galli) and tapeworms (Raillietina spiralis). Each species of worm was placed into a negative control group, an albendazole treatment group, or a V. thapsus treatment group, and the time taken for paralysis and death was determined. In addition, relaxation activity tests were performed on sections of rabbit's jejunum. Plant extracts were tested on KCl-induced contractions and the relaxation activities were quantified against atropine. V. thapsus calcium chloride curves were constructed to investigate the mode of action of the plant extracts. RESULTS: We detected flavonoids, saponins, tannins, terpenoids, glycosides, carbohydrates, proteins, fats and fixed oils in V. thapsus. For both species of worm, paralysis occurred fastest at the highest concentration of extract. The relative index values for paralysis in A. galli were 4.58, 3.41 and 2.08, at concentrations of 10, 20 and 40 mg/ml of plant extract, respectively. The relative index for death in A. galli suggested that V. thapsus extract is wormicidal at high concentration. Similarly, the relative indexes for paralysis and death in R. spiralis suggested that the extract is a more potent wormicidal agent than albendazole. The mean EC(50) relaxation activity values for spontaneous and KCl induced contractions were 7.5 ± 1.4 mg/ml (6.57-8.01, n = 6) and 7.9 ± 0.41 mg/ml (7.44-8.46, n = 6), respectively. The relaxation activity of the extract was 11.42 ± 2, 17.0 ± 3, 28.5 ± 4, and 128.0 ± 7% of the maximum observed for atropine at corresponding concentrations. The calcium chloride curves showed that V. thapsus extracts (3 mg/ml), had a mean EC(50) (log molar [calcium]) value of -1.9 ± 0.06 (-1.87 - -1.98, n = 6) vs. control EC(50) = -2.5 ± 0.12 (-2.37 - -2.56, n = 6), whereas the verapamil (0.1 µM) EC(50) was -1.7 ± 0.1 (-1.6 - -1.8, n = 6) vs. control EC(50) = -2.4 ± 0.09 (-2.3 - -2.47, n = 5). CONCLUSIONS: Our results suggest that V. thapsus, which is currently used by some tribes in the Malakand region of Pakistan, has anthelmintic and antispasmodic value.


Assuntos
Anti-Helmínticos/farmacologia , Helmintíase Animal/tratamento farmacológico , Helmintos/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Parassimpatolíticos/farmacologia , Extratos Vegetais/farmacologia , Verbascum , Albendazol/farmacologia , Animais , Ascaridia/efeitos dos fármacos , Atropina/farmacologia , Cestoides/efeitos dos fármacos , Helmintíase Animal/complicações , Helmintíase Animal/mortalidade , Jejuno/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Paralisia/etiologia , Paralisia/prevenção & controle , Cloreto de Potássio , Coelhos , Espasmo/induzido quimicamente , Espasmo/tratamento farmacológico , Vasodilatadores/farmacologia , Verapamil/farmacologia
10.
BMC Complement Altern Med ; 11: 106, 2011 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-22051373

RESUMO

BACKGROUND: Saponins isolated from plant sources have a number of traditional and industrial applications. Saponins have pharmacological effects like anti-inflammatory, molluscicidal, antimicrobial, antispasmodic, antidiabetic, anticancer, anticonvulsant, anthelmintic, antitussive and cytotoxic activities. The current work describes the anthelmintic and cytotoxic activities of crude saponins of Achillea Wilhelmsii and Teucrium Stocksianum as these plants are rich with saponins. METHODS: Brine shrimp cytotoxic activity of crude saponins was determined by Meyer et al. (1982) at test concentrations of 1000 µg/ml, 100 µg/ml, 10 µg/ml, 7.5 µg/ml, 5.0 µg/ml, 2.5 µg/ml and 1.25 µg/ml. Percentage mortality of test concentrations was determined. Similarly, in vitro anthelmintic activity was determined against roundworms, tapeworms and earthworms. Albendazole and piperazine citrate at concentration 10 mg/ml were used as standard anthelmintic drugs. RESULTS: Crude saponins of Achillea wilhelmsii (CSA) and Teucrium stocksianum (CST) had, respectively, cytotoxic activity with LC50 values 2.3±0.16 and 5.23±0. 34 µg/ml. For in vitro anthelmintic activity, time for paralysis and death of parasites (parasiticidal activity) was noted. At concentration 40 mg/ml, crude saponins of Achillea wilhelmsii are 1.96 and 2.12 times more potent than albendazole against Pheretima posthuma and Raillietina spiralis, respectively. Similarly, at concentration 40 mg/ml, crude saponins of Teucrium stocksianum (CST) has 1.89, 1.96 and 1.37 times more parasiticidal activity than albendazole against Pheretima posthuma, Raillietina spiralis and Ascardia galli, respectively. CONCLUSION: Crude saponins of Achillea wilhelmsii and Teucrium stocksianum have cytotoxic and anthelmintic activity. The crude saponins may be excellent sources of cytotoxic and anthelmintic constituents that warrant its isolation and purification for new drug development.


Assuntos
Achillea/química , Anti-Helmínticos/farmacologia , Citotoxinas/farmacologia , Extratos Vegetais/farmacologia , Saponinas/farmacologia , Teucrium/química , Animais , Artemia/efeitos dos fármacos , Helmintos/efeitos dos fármacos , Dose Letal Mediana
11.
BMC Complement Altern Med ; 11: 99, 2011 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-22024247

RESUMO

BACKGROUND: Callistemon citrinus Curtis belongs to family Myrtaceae that has a great medicinal importance. In our previous work, fruits of Callistemon citrinus were reported to have relaxant (antispasmodic) activity. The current work describes the screening of fractions of the crude methanol extract for tracing spasmolytic constituents so that it shall help us for isolation of bioactive compounds. Acute toxicity and brine shrimp cytotoxicity of crude methanol extract are also performed to standardize it. METHODS: The crude methanol extract was obtained by maceration with distilled water (500 ml) three times and fractionated successively with n-hexane, chloroform, ethyl acetate and n-butanol (300 ml of each solvent). Phytochemical analysis for crude methanol extract was performed. Acute toxicity studies were performed in mice. Brine shrimp cytotoxicity studies were performed to determine its cytotoxicity and standardize it. In other series of experiments, rabbits' jejunum preparations were used in screening for possible relaxant activities of various fractions. They were applied in concentrations of 0.01, 0.03, 0.1, 0.3, 1.0, 3.0, 5.0 and 10.0 mg/ml on spontaneous rabbits' jejunum preparations. In similar fashion, fractions were also tested on KCl (80 mM) -induced contractions. Calcium chloride curves were constructed in K-rich Tyrode's solution. The effects of various fractions were tested on calcium chloride curves at concentrations 1.0, 3.0, 5.0 and 10.0 mg/ml. Curves of verapamil used as reference drug at concentration 0.1 µM and 0.3 µM were also constructed. The curves were compared with their respective controls for possible right shift. RESULTS: Methanol extract tested strongly positive for saponins and tannins. However, it tested mild positive for presence of proteins, amino acids, carbohydrates and phenolic compounds. LD(50) value for crude methanol extract is 476.25 ± 10.3 (470-481, n = 4) mg/ml. Similarly, EC(50) value for brine shrimp cytotoxicity is 65.5 ± 7.28 (60.8- 69.4, n = 4) mg/ml. All the fractions relaxed the spontaneous and KCl-induced contractions. EC(50) values (mg/ml) for effects of ethyl acetate fraction on spontaneous and KCl induced contractions are 2.62 ± 0.78 (2.15-3.0, n = 4) and 3.72 ± 0.86 (3.38-4.28, n = 4) respectively. Respective EC(50) values (mg/ml) for n-butanol fraction are 3.59 ± 0.2(3.07-3.9, n = 4) for spontaneous, and 5.57 ± 0.2 (5.07-6.11, n = 4) for KCl- induced contractions. EC(50) value for control calcium chloride curve (without extract) is -2.73 ± 0.19 (-2.6 - -2.81, n = 4) while EC(50) for curves treated with 5.0 mg/ml of chloroform is -2.22 ± 0.02 (-2.16 - -2.3, n = 4). EC(50) value for ethyl acetate treated (1.0 mg/ml) tissues is -1.95 ± 0.10 (-1.88 - -2.0, n = 4) vs. control EC(50) = -2.71 ± 0.08 (-2.66 - -2.76, n = 4). All the fractions, except n-hexane, showed a right shift like that of verapamil (EC(50) = -1.72 ± 0.15 (-1.62 - -1.8, n = 4) vs. Control EC(50) = -2.41 ± 0.06 (-2.38 - - 2.44, n = 4), a standard drug that blocks voltage operated calcium channels. CONCLUSION: Relaxant constituents were more concentrated in ethylacetate fraction followed by chloroform, n -butanol and aqueous fractions that warrant for its isolation. The crude methanol extract is safe at concentration 250 mg/ml or below and results of brine shrimp cytotoxicity assay imply the plant specie may be a source of cytotoxic agents.


Assuntos
Artemia/efeitos dos fármacos , Myrtaceae/química , Parassimpatolíticos/farmacologia , Extratos Vegetais/farmacologia , Animais , Feminino , Frutas/química , Jejuno/efeitos dos fármacos , Jejuno/fisiologia , Masculino , Camundongos , Contração Muscular/efeitos dos fármacos , Parassimpatolíticos/toxicidade , Extratos Vegetais/toxicidade , Coelhos
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