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61.
Ahmad B Khan H Bashir S Nisar M Hassan M 《Journal of enzyme inhibition and medicinal chemistry》2006,21(4):449-452
In vitro enzymes inhibition activities of the crude methanolic extract and various fractions of Colchicum luteum Baker (Liliaceae) including chloroform, ethyl acetate, n-butanol and aqueous were carried out against actylcholinesterase, butyrylcholinesterase, lipoxygenase and urease enzymes. A significant enzyme inhibition activity (89%) is shown by the crude methanolic extract and its fractions against lipoxygenase, while low to significant activity (32-75%) was evident against butyrylcholinesterase. The crude methanolic extract and its various fractions demonstrated low activity (29-61%) against acetylcholinesterase and no activity against urease. 相似文献
62.
Charney AN Egnor RW Henner D Rashid H Cassai N Sidhu GS 《American journal of physiology. Cell physiology》2004,286(5):C1062-C1070
In rat ileum and colon, apical membrane exchange and net Cl- absorption are stimulated by increases in PCO2 or . Because changes in PCO2 stimulate colonic Na+ absorption, in part, by modulating vesicular trafficking of the Na+/H+ exchanger type 3 isoform to and from the apical membrane, we examined whether changes in PCO2 affect net Cl- absorption by modulating vesicular trafficking of the exchanger anion exchanger (AE)1. Cl- transport across rat distal ileum and colon was measured in the Ussing chamber, and apical membrane protein biotinylation of these segments and Western blots of recovered proteins were performed. In colonic epithelial apical membranes, AE1 protein content was greater at PCO2 70 mmHg than at PCO2 21 mmHg but was not affected by pH changes in the absence of CO2. AE1 was internalized when PCO2 was reduced and exocytosed when PCO2 was increased, and both mucosal wortmannin and methazolamide inhibited exocytosis. Wortmannin also inhibited the increase in colonic Cl- absorption caused by an increase in PCO2. Increases in PCO2 stimulated ileal Cl- absorption, but wortmannin was without effect. Ileal epithelial apical membrane AE1 content was not affected by PCO2. We conclude that CO2 modulation of colonic, but not ileal, Cl- absorption involves effects on vesicular trafficking of AE1. PCO2; ileum; colon; anion exchanger 1; Na+/H+ exchanger type 3 相似文献
63.
Ansari MA Ahmad AS Ahmad M Salim S Yousuf S Ishrat T Islam F 《Biological trace element research》2004,101(1):73-86
Normal cellular metabolism produces oxidants that are neutralized by the cells' antioxidant enzymes and antioxidants taken
from outside. An imbalance between oxidant and antioxidant has been postulated to lead to the neurodegeneration in the ischemic
condition. In this study, we have demonstrated the prevention or slowdown of neuronal injury in middle cerebral artery occlusion
(MCAO) by sodium selenite. Rats were pretreated with 0.05, 0.1, and 0.2 mg/kg body wt of sodium selenite for 7 d. The rats
of group I (sham) and group II (ischemia) were pretreated with physiological saline for 7 d. On d 8, MCAO was induced for
2 h in, the right side of brain of group II, III, IV, and V rats. Brains were dissect out after 22 h of reperfusion and washed
with chilled physiological saline. The right cerebral hemisphere was used for the preparation of mitochondria. The activity
of superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, and monoamine oxidase (MAO-A and MAO-B) was depleted significantly; conversely, the activity of poly(ADP-ribosyl)
polymerase was elevated significantly as compared to the sham, and the pretreatment of the animals with different doses of
sodium selenite has protected the activity of these enzymes significantly. The content of glutathione was decreased significantly,
whereas the level of lipid peroxidation was increased significantly in the mitochondria of MCAO as compared to the sham group,
and pretreatment with different doses of sodium selenite has protected their levels significantly as compared to the MCAO
group. It is concluded that selenium, which is an essential part of our diet, might be helpful in protection against neurodegeneration
in cerebral ischemia. 相似文献
64.
Muhammad Asad Rashad Rasool Khan Ahmed B. Aljuboory Muhammad Haroon U. Rashid Uttam Kumar Inzamam Ul Haq Aqsa Hafeez Ahmed Noureldeen Khadiga Alharbi 《Phyton》2023,92(4):1161-1172
The beet armyworm (BAW), Spodoptera exigua (Lepidoptera: Noctuidae) is a highly destructive pest of vegetables and
field crops. Management of beet armyworm primarily relies on synthetic pesticides, which is threatening the beneficial
community and environment. Most importantly, the BAW developed resistance to synthetic pesticides with making it
difficult to manage. Therefore, alternative and environment-friendly pest management tactics are urgently required.
The use of pesticidal plant extracts provides an effective way for a sustainable pest management program. To evaluate
the use of pesticidal plant extracts against BAW, we selected six plant species (Lantana camara, Aloe vera, Azadirachta
indica, Cymbopogon citratus, Nicotianatabacum, and Ocimum basilicum) for initial screening experiment. Four out of
six plant species such as A. indica, N. tabacum, C. citratus and O. basilicum showed promising mortality of more than
50%. Therefore, we selected these four plant extracts for the subsequent experiments. Through contact bioassay, A.
indica showed high mortality 66.63%, followed by the N. tabacum 53.33%, at 10% w/v concentration. Similarly, N.
tabacum showed the highest mortality rate, 66% at 10% w/v concentration, followed by the A. indica 46% through
feeding bioassay. Furthermore, the feeding deterrence assay showed that C. citratus had a high antifeedant index
(−50) followed by A. indica (−39), and N. tabacum (−28). In living plant assay, the N. tabacum extract showed a
low mean damage score 3.6 on living cotton plant followed by C. citratus 4.5 and A. indica 5.5. Hence, extracts of
three plant species provided promising results against the BAW, which can minimize the use of synthetic chemicals,
particularly for small landholding farmers. Further studies are also required to evaluate the effects of these plant extract
against BAW on cotton plants under field conditions to optimize the further use. 相似文献
65.
66.
Ahmad M Saleem S Ahmad AS Yousuf S Ansari MA Khan MB Ishrat T Chaturvedi RK Agrawal AK Islam F 《Journal of neurochemistry》2005,93(1):94-104
Ginkgo biloba extract (EGb), a potent antioxidant and monoamine oxidase B (MAO-B) inhibitor, was evaluated for its anti-parkinsonian effects in a 6-hydroxydopamine (6-OHDA) rat model of the disease. Rats were treated with 50, 100, and 150 mg/kg EGb for 3 weeks. On day 21, 2 microL 6-OHDA (10 microg in 0.1% ascorbic acid saline) was injected into the right striatum, while the sham-operated group received 2 microL of vehicle. Three weeks after 6-OHDA injection, rats were tested for rotational behaviour, locomotor activity, and muscular coordination. After 6 weeks, they were killed to estimate the generation of thiobarbituric acid reactive substances (TBARS) and reduced glutathione (GSH) content, to measure activities of glutathione-S-transferase (GST), glutathione reductase (GR), glutathione peroxidase (GPx), catalase, and superoxide dismutase (SOD), and to quantify catecholamines, dopamine (DA) D2 receptor binding, and tyrosine hydroxylase-immunoreactive (TH-IR) fibre density. The increase in drug-induced rotations and deficits in locomotor activity and muscular coordination due to 6-OHDA injections were significantly and dose-dependently restored by EGb. The lesion was followed by an increased generation of TBARS and significant depletion of GSH content in substantia nigra, which was gradually restored with EGb treatment. EGb also dose-dependently restored the activities of glutathione-dependent enzymes, catalase, and SOD in striatum, which had reduced significantly by lesioning. A significant decrease in the level of DA and its metabolites and an increase in the number of dopaminergic D2 receptors in striatum were observed after 6-OHDA injection, both of which were significantly recovered following EGb treatment. Finally, all of these results were exhibited by an increase in the density of TH-IR fibers in the ipsilateral substantia nigra of the lesioned group following treatment with EGb; the lesioning had induced almost a complete loss of TH-IR fibers. Considering our behavioural studies, biochemical analysis, and immunohistochemical observation, we conclude that EGb can be used as a therapeutic approach to check the neuronal loss following parkinsonism. 相似文献
67.
68.
Haroon Khan Murad Ali Khan Tahira Mahmood Muhammad Iqbal Choudhary 《Journal of enzyme inhibition and medicinal chemistry》2013,28(6):855-859
The methanol extract of the rhizomes of Gloriosa superba Linn (Colchicaceae) and its subsequent fractions in different solvent systems were screened for antibacterial and antifungal activities. Excellent antifungal sensitivity was expressed by the n-butanol fraction against Candida albicans and Candida glaberata (up to 90%) and against Trichophyton longifusus (78%) followed by the chloroform fraction against Microsporum canis (80%). In the antibacterial bioassay, the crude extract and subsequent fractions showed mild to moderate antibacterial activities. Chloroform fraction displayed highest antibacterial sensitivity against Staphylococcus aureous (88%) followed by the crude extract (59%). The total phenol content of the crude extract and fractions of the plant expressed no significant correlation with the antimicrobial activities. 相似文献
69.
Hanif Sajid Saleem Muhammad Farrukh Sarwar Muhammad Irshad Muhammad Shakoor Abdul Wahid Muhammad Ashfaq Khan Haroon Zaman 《Journal of Plant Growth Regulation》2021,40(1):305-312
Journal of Plant Growth Regulation - Abiotic stresses are the prime coercion to sustainable crop production in changing climate scenario. Heat and drought stresses at reproductive as well as... 相似文献
70.
Atif F Sayeed I Yousuf S Ishrat T Hua F Wang J Brat DJ Stein DG 《Molecular medicine (Cambridge, Mass.)》2011,17(9-10):1084-1094
We investigated the antitumorogenic effects of progesterone (P4) in a human neuroblastoma (SK-N-AS) cell line in vitro and in a mouse xenograft model of neuroblastoma. The safety of P4 was tested in rat primary cortical neurons and human foreskin fibroblasts (HFF-1). At high doses, P4 significantly (P < 0.05) decreased SK-N-AS cell viability in vitro, and this effect was not blocked either by 5α-reductase inhibitor, finasteride or the P4 receptor antagonist RU486. Even at very high doses, P4 did not induce any cell death in healthy primary cortical neurons or HFF-1. The bioavailability of P4 24 h after the last injection in the serum of treated animals was significantly (P < 0.05) higher (10-33 μg/mL) than in untreated animals. In nude mice, P4 (50 and 100 mg/kg) inhibited neuroblastoma growth by ~50% over 8 d of treatment. No drug toxicity was observed in the mice, as measured by body weight and activity. P4 suppressed the expression of vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMP-9, MMP-2), which are involved in tumor vascular development. High-dose P4 inhibited tumor growth by suppressing cell proliferation and inducing apoptosis, as evidenced by the expression of proliferating cell nuclear antigen and cleaved caspase-3. P4 significantly increased the expression of P4 receptor isoform-A and suppressed phospho-Akt (Ser437) expression. In conclusion, at high doses, P4 effectively inhibits the growth of solid neuroblastoma tumor and has high bioavailability, selective toxicity and a high margin of safety, making it a possible candidate for further study as a potential clinical treatment of neuroblastoma. 相似文献