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11.
Shukla Pawan Reddy Ramesha A. Ponnuvel Kangayam M. Rohela Gulab Khan Shabnam Aftab A. Ghosh M. K. Mishra Rakesh Kumar 《Molecular biology reports》2019,46(2):1809-1817
Molecular Biology Reports - Mulberry (Morus alba L.) is the sole food source for the mulberry silkworm, Bombyx mori and therefore important for sericulture industry. Different abiotic stress... 相似文献
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Koenitzer JR Isbell TS Patel HD Benavides GA Dickinson DA Patel RP Darley-Usmar VM Lancaster JR Doeller JE Kraus DW 《American journal of physiology. Heart and circulatory physiology》2007,292(4):H1953-H1960
Hydrogen sulfide (H(2)S) has recently been shown to have a signaling role in vascular cells. Similar to nitric oxide (NO), H(2)S is enzymatically produced by amino acid metabolism and can cause posttranslational modification of proteins, particularly at thiol residues. Molecular targets for H(2)S include ATP-sensitive K(+) channels, and H(2)S may interact with NO and heme proteins such as cyclooxygenase. It is well known that the reactions of NO in the vasculature are O(2) dependent, but this has not been addressed in most studies designed to elucidate the role of H(2)S in vascular function. This is important, since H(2)S reactions can be dramatically altered by the high concentrations of O(2) used in cell culture and organ bath experiments. To test the hypothesis that the effects of H(2)S on the vasculature are O(2) dependent, we have measured real-time levels of H(2)S and O(2) in respirometry and vessel tension experiments, as well as the associated vascular responses. A novel polarographic H(2)S sensor developed in our laboratory was used to measure H(2)S levels. Here we report that, in rat aorta, H(2)S concentrations that mediate rapid contraction at high O(2) levels cause rapid relaxation at lower physiological O(2) levels. At high O(2), the vasoconstrictive effect of H(2)S suggests that it may not be H(2)S per se but, rather, a putative vasoactive oxidation product that mediates constriction. These data are interpreted in terms of the potential for H(2)S to modulate vascular tone in vivo. 相似文献
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Himani Awasthi Santoshkumar Tota Kashif Hanif Chandiswar Nath Rakesh Shukla 《Life sciences》2010,86(3-4):87-94
AimsThe aim of the present study is to investigate the effect of curcumin on cerebral blood flow (CBF), memory impairment, oxidative stress and cholinergic dysfunction in intracerebral (IC) streptozotocin (STZ) induced memory impairment in mice.Main methodsMemory impairment was induced by STZ (0.5 mg/kg, IC) administered twice with an interval of 48 h in mice. Memory function was assessed by Morris water maze and passive avoidance test. CBF was measured by Laser Doppler Flowmetry (LDF). To study the preventive effect, curcumin (10, 20 and 50 mg/kg, PO) was administered for 21 days starting from the first dose of STZ. In another set of experiment, curcumin was administered for 7 days from 19th day after confirming STZ induced dementia to observe its therapeutic effect. Biochemical parameters of oxidative stress and cholinergic function were estimated in brain on day 21.Key findingsThe major finding of this study is that STZ (IC) caused a significant reduction in CBF along with memory impairment, cholinergic dysfunction and enhanced oxidative stress. Curcumin dose dependently improved CBF in STZ treated mice together with amelioration of memory impairment both in preventive and therapeutic manner.SignificanceThe present study clearly demonstrates the beneficial effects of curcumin, the dietary staple of India, on CBF, memory and oxidative stress which can be exploited for dementia associated with age related vascular and neurodegenerative disorders. 相似文献
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Mayank Singh Clayton R. Hunt Raj K. Pandita Rakesh Kumar Chin-Rang Yang Nobuo Horikoshi Robert Bachoo Sara Serag Michael D. Story Jerry W. Shay Simon N. Powell Arun Gupta Jessie Jeffery Shruti Pandita Benjamin P. C. Chen Dorothee Deckbar Markus L?brich Qin Yang Kum Kum Khanna Howard J. Worman Tej K. Pandita 《Molecular and cellular biology》2013,33(16):3390
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Beneficial effects of n-hexane bark extract of Onosma echioides L. on diabetic peripheral neuropathy
Ambreen Shoaib Badruddeen Rakesh Kumar Dixit Magdah Ganash George Barreto Ghulam Md Ashraf Hefazat Hussain Siddiqui 《Journal of cellular biochemistry》2019,120(10):16524-16532
Onosma echioides Linn (Boraginaceae) is the most frequently used curative herb widely used for kidney obstruction, sciatic pain, and gout. The present study was designed to investigate the therapeutic effects of n-hexane bark extract of O. echioides (OE) L. root in vivo against Streptozotocin-induced diabetic neuropathy in SD rats. For in vivo activity, the experiment was categorized into five different groups (n = 5). Group-I was considered as nondiabetic/normal control (NC) treated with 0.5% carboxymethyl cellulose (CMC), Group II as diabetic control, Group-III, IV, and V served as diabetic treated with OE 50, OE 100, and pregabalin at a dose of 50, 100, and 10 mg/kg body weight, orally, respectively. Body weight, blood glucose, oral glucose tolerance test, behavioral studies (motor coordination test, thermal hyperalgesia, cold allodynia, locomotor activity, oxidative biomarkers (thio barbituric acid reactive substances [TBARS], superoxide dismutase [SOD], glutathione [GSH], and catalase), and histopathology of the sciatic nerve were performed. Treatment with OE showed a dose-dependent increase in neuroprotective activity by improving the myelination and decreasing the axonal swelling of nerve fibers. The verdicts of behavioral activities showed a remarkable effect on animals after the treatment of extract and standard drug pregabalin. In conclusion, our findings supported the traditional application of OE and explored its importance in the management of diabetic neuropathy. Additional clinical experiments may provide novel therapeutic drugs for diabetes and its complications. 相似文献
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Porwal S Kumar T Lal S Rani A Kumar S Cheema S Purohit HJ Sharma R Singh Patel SK Kalia VC 《Bioresource technology》2008,99(13):5444-5451
Thirty five bacterial isolates from diverse environmental sources such as contaminated food, nitrogen rich soil, activated sludges from pesticide and oil refineries effluent treatment plants were found to belong to Bacillus, Bordetella, Enterobacter, Proteus, and Pseudomonas sp. on the basis of 16S rRNA gene sequence analysis. Under dark fermentative conditions, maximum hydrogen (H2) yields (mol/mol of glucose added) were recorded to be 0.68 with Enterobacter aerogenes EGU16 followed by 0.63 with Bacillus cereus EGU43 and Bacillus thuringiensis EGU45. H2 constituted 63–69% of the total biogas evolved. Out of these 35 microbes, 18 isolates had the ability to produce polyhydroxybutyrate (PHB), which varied up to 500 mg/l of medium, equivalent to a yield of 66.6%. The highest PHB yield was recorded with B. cereus strain EGU3. Nine strains had high hydrolytic activities (zone of hydrolysis): lipase (34–38 mm) – Bacillus sphaericus strains EGU385, EGU399 and EGU542; protease (56–62 mm) – Bacillus sp. strains EGU444, EGU447 and EGU445; amylase (23 mm) – B. thuringiensis EGU378, marine bacterium strain EGU409 and Pseudomonas sp. strain EGU448. These strains with high hydrolytic activities had relatively low H2 producing abilities in the range of 0.26–0.42 mol/mol of glucose added and only B. thuringiensis strain EGU378 had the ability to produce PHB. This is the first report among the non-photosynthetic microbes, where the same organism(s) – B. cereus strain EGU43 and B. thuringiensis strain EGU45, have been shown to produce H2 – 0.63 mol/mol of glucose added and PHB – 420–435 mg/l medium. 相似文献