13C-2H correlation NMR spectroscopy studies of the in vivo transformations of natural products from Artemisia annua

2003 ◽  
Vol 2 (1-2) ◽  
pp. 45-59 ◽  
Author(s):  
G.D. Brown
Keyword(s):  
Natural Products ◽  
Nmr Spectroscopy ◽  
Artemisia Annua ◽  
Spectroscopy Studies

Adult Rat Brain-Slice Preparation for Nuclear Magnetic Resonance Spectroscopy Studies of Hypoxia

1996 ◽  
Vol 84 (1) ◽  
pp. 201-210 ◽  
Author(s):  
Maryceline T. Espanol ◽  
Lawrence Litt ◽  
Lee-Hong Chang ◽  
Thomas L. James ◽  
Philip R. Weinstein ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
Ex Vivo ◽  
Brain Slices ◽  
Adult Brain ◽  
Adult Rat ◽  
Spectroscopy Studies ◽  
Lactate Peak

Background When perfused neonatal brain slices are studied ex vivo with nuclear magnetic resonance (NMR) spectroscopy, it is possible to use 31P detection to monitor levels of intracellular adenosine triphosphate (ATP), cytosolic pH, and other high-energy phosphates and 1H detection to monitor lactate and glutamate. Adult brain slices of high metabolic integrity are more difficult to obtain for such studies, because the adult cranium is thicker, and postdecapitation revival time is shorter. A common clinical anesthesia phenomenon--loss of temperature regulation during anesthesia, with surface cooling and deep hypothermia, was used to obtain high-quality adult rat cerebrocortical slices for NMR studies. Methods Spontaneously breathing adult rats (350 g), anesthetized with isoflurane in a chamber, were packed in ice and cooled until rectal temperatures decreased to approximately 30 degrees C. An intraaortic injection of heparinized saline at 4 degrees C further cooled the brain to approximately 18 degrees C. Slices were obtained and then recovered at 37 degrees C in oxygenated medium. Interleaved 31P/1H NMR spectra were acquired continually before, during, and after 20 min of no-flow hypoxia (PO2 approximately 0 mmHg). Histologic (Nissl stain) measurements were made from random slices removed at different times in the protocol. Three types of pretreatment were compared in no-flow hypoxia studies. The treatments were: (1) hyperoxia; (2) hypercapnia (50% CO2); and (3) hypoxia, which was accomplished by washing the slices with perfusate equilibrated with 100% N2 and maintaining a 100% N2 gas flow in the air space above the perfusate. Results During hyperoxia, 31P NMR metabolite ratios were identical to those seen in vivo in adult brains, except that, in vitro, the Pi peak was slightly larger than in vivo. A lactate peak was seen in in vitro 1H spectra of slices after metabolic recovery from decapitation, although lactate is barely detectable in vivo in healthy brains. The in vitro lactate peak was attributed to a small population of metabolically impaired cells in an injury layer at the cut edge. NMR spectral resolution from the solenoidal coil exceeded that obtained in vivo in surface coil experiments. Phosphocreatine and ATP became undetectable during oxygen deprivation, which also caused a three- to sixfold increase in the ratio of lactate to N-acetyl-aspartate. Within experimental error, all metabolite concentrations except pHi recovered to control values within 2 h after oxygen restoration. Nissl-stained sections suggested that pretreatment with hypercapnia protected neurons from cell swelling during the brief period of no-flow oxygen deprivation. Conclusions Perfused, respiring adult brain slices having intact metabolic function can be obtained for NMR spectroscopy studies. Such studies have higher spectral resolution than can be obtained in vivo. During such NMR experiments, one can deliver drugs or molecular probes to brain cells and obtain brain tissue specimens for histologic and immunochemical measures of injury. Important ex vivo NMR spectroscopy studies that are difficult or impossible to perform in vivo are feasible in this model.

Changes in the metabolic profiles of the serum and putamen in Parkinson’s disease patients – In vitro and in vivo NMR spectroscopy studies

2020 ◽  
Vol 1748 ◽  
pp. 147118 ◽  
Author(s):  
Beata Toczylowska ◽  
Elzbieta Zieminska ◽  
Małgorzata Michałowska ◽  
Malgorzata Chalimoniuk ◽  
Urszula Fiszer
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Nmr Spectroscopy ◽  
Metabolic Profiles ◽  
In Vivo Nmr ◽  
In Vivo Nmr Spectroscopy ◽  
Spectroscopy Studies

Natural Anti-inflammatory compounds as Drug candidates in Alzheimer’s disease

2020 ◽  
Vol 27 ◽  
Author(s):  
Reyaz Hassan Mir ◽  
Abdul Jalil Shah ◽  
Roohi Mohi-ud-din ◽  
Faheem Hyder Potoo ◽  
Mohd. Akbar Dar ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Natural Products ◽  
Protective Action ◽  
New Drugs ◽  
Huperzine A ◽  
Brain Disorder ◽  
Anti Inflammatory

: Alzheimer's disease (AD) is a chronic neurodegenerative brain disorder characterized by memory impairment, dementia, oxidative stress in elderly people. Currently, only a few drugs are available in the market with various adverse effects. So to develop new drugs with protective action against the disease, research is turning to the identification of plant products as a remedy. Natural compounds with anti-inflammatory activity could be good candidates for developing effective therapeutic strategies. Phytochemicals including Curcumin, Resveratrol, Quercetin, Huperzine-A, Rosmarinic acid, genistein, obovatol, and Oxyresvertarol were reported molecules for the treatment of AD. Several alkaloids such as galantamine, oridonin, glaucocalyxin B, tetrandrine, berberine, anatabine have been shown anti-inflammatory effects in AD models in vitro as well as in-vivo. In conclusion, natural products from plants represent interesting candidates for the treatment of AD. This review highlights the potential of specific compounds from natural products along with their synthetic derivatives to counteract AD in the CNS.

Potential for Treatment of Neurodegenerative Diseases with Natural Products or Synthetic Compounds that Stabilize Microtubules

2020 ◽  
Vol 26 (35) ◽  
pp. 4362-4372
Author(s):  
John H. Miller ◽  
Viswanath Das
Keyword(s):  
Natural Products ◽  
Neurodegenerative Diseases ◽  
In Vivo Models ◽  
Synthetic Compounds ◽  
Stabilizing Agents ◽  
Animal Models Of Disease ◽  
Model Studies ◽  
Models Of Disease

No effective therapeutics to treat neurodegenerative diseases exist, despite significant attempts to find drugs that can reduce or rescue the debilitating symptoms of tauopathies such as Alzheimer’s disease, Parkinson’s disease, frontotemporal dementia, amyotrophic lateral sclerosis, or Pick’s disease. A number of in vitro and in vivo models exist for studying neurodegenerative diseases, including cell models employing induced-pluripotent stem cells, cerebral organoids, and animal models of disease. Recent research has focused on microtubulestabilizing agents, either natural products or synthetic compounds that can prevent the axonal destruction caused by tau protein pathologies. Although promising results have come from animal model studies using brainpenetrant natural product microtubule-stabilizing agents, such as paclitaxel analogs that can access the brain, epothilones B and D, and other synthetic compounds such as davunetide or the triazolopyrimidines, early clinical trials in humans have been disappointing. This review aims to summarize the research that has been carried out in this area and discuss the potential for the future development of an effective microtubule stabilizing drug to treat neurodegenerative disease.

Novel Phytochemical Constituents and their Potential to Manage Diabetes

2020 ◽  
Vol 26 ◽  
Author(s):  
Shaik Ibrahim Khalivulla ◽  
Arifullah Mohammed ◽  
Kokkanti Mallikarjuna
Keyword(s):  
Natural Products ◽  
Large Population ◽  
World Health ◽  
In Vivo Studies ◽  
Antidiabetic Activity ◽  
Therapeutic Drug ◽  
Pharmacological Activities ◽  
Chemical Structures

Background: Diabetes is a chronic disease affecting a large population worldwide and stands as one of the major global health challenges to be tackled. According to World Health Organization, about 400 million are having diabetes worldwide and it is the seventh leading cause of deaths in 2016. Plant based natural products had been in use from ancient time as ethnomedicine for the treatment of several diseases including diabetes. As a result of that, there are several reports on plant based natural products displaying antidiabetic activity. In the current review, such antidiabetic potential compounds reported from all plant sources along with their chemical structures are collected, presented and discussed. This kind of reports are essential to pool the available information to one source followed by statistical analysis and screening to check the efficacy of all known compounds in a comparative sense. This kind of analysis can give rise to few numbers of potential compounds from hundreds, whom can further be screened through in vitro and in vivo studies, and human trails leading to the drug development. Methods: Phytochemicals along with their potential antidiabetic property were classified according to their basic chemical skeleton. The chemical structures of all the compounds with antidiabetic activities were elucidated in the present review. In addition to this, the distribution and their other remarkable pharmacological activities of each species is also included. Results: The scrutiny of literature led to identification of 44 plants with antidiabetic compounds (70) and other pharmacological activities. For the sake of information, the distribution of each species in the world is given. Many plant derivatives may exert antidiabetic properties by improving or mimicking the insulin production or action. Different classes of compounds including sulfur compounds (1-4), alkaloids (5-11), phenolic compounds (12-17), tannins (18-23), phenylpropanoids (24-27), xanthanoids (28-31), amino acid (32), stilbenoid (33), benzofuran (34), coumarin (35), flavonoids (36-49) and terpenoids (50-70) were found to be active potential compounds for antidiabetic activity. Of the 70 listed compounds, majorly 17 compounds are from triterpenoids, 13 flavonoids and 7 are from alkaloids. Among all the 44 plant species, maximum number (7) of compounds are reported from Lagerstroemia speciosa followed by Momordica charantia (6) and S. oblonga with 5 compounds. Conclusion: This is the first paper to summarize the established chemical structures of phytochemicals that have been successfully screened for antidiabetic potential and their mechanisms of inhibition. The reported compounds could be considered as potential lead molecules for the treatment of type-2 diabetes. Further, molecular and clinical trials are required to select and establish the therapeutic drug candidates.

Combinatorial Synthesis of Novel 9R-Acyloxyquinine Derivatives as Insecticidal Agents

2020 ◽  
Vol 23 (2) ◽  
pp. 111-118
Author(s):  
Zhiping Che ◽  
Jinming Yang ◽  
Di Sun ◽  
Yuee Tian ◽  
Shengming Liu ◽  
...  
Keyword(s):  
Natural Products ◽  
Double Bond ◽  
Insecticidal Activity ◽  
Structural Modification ◽  
Combinatorial Synthesis ◽  
Hydroxyl Group ◽  
Botanical Insecticide ◽  
Mythimna Separata ◽  
Lead Compounds

Background: It is one of the effective ways for pesticide innovation to develop new insecticides from natural products as lead compounds. Quinine, the main alkaloid in the bark of cinchona tree as well as in plants in the same genus, is recognized as a safe and potent botanical insecticide to many insects. The structural modification of quinine into 9R-acyloxyquinine derivatives is a potential approach for the development of novel insecticides, which showed more toxicity than quinine. However, there are no reports on the insecticidal activity of 9Racyloxyquinine derivatives to control Mythimna separata. Methods: Endeavor to discover biorational natural products-based insecticides, 20 novel 9Racyloxyquinine derivatives were prepared and assessed for their insecticidal activity against M. separata in vivo by the leaf-dipping method at 1 mg/mL. Results: Among all the compounds, especially derivatives 5i, 5k and 5t exhibited the best insecticidal activity with final mortality rates of 50.0%, 57.1%, and 53.6%, respectively. Conclusion: Overall, a free 9-hydroxyl group is not a prerequisite for insecticidal activity and C9- substitution is well tolerated; modification of out-ring double-bond is acceptable, and hydrogenation of double-bond enhances insecticidal activity; Quinine ring is essential and open of it is not acceptable. These preliminary results will pave the way for further modification of quinine in the development of potential new insecticides.

Modulation of Matrix Metalloproteinases by Plant-Derived Products

2020 ◽  
Vol 20 ◽  
Author(s):  
Nur Najmi Mohamad Anuar ◽  
Nurul Iman Natasya Zulkafali ◽  
Azizah Ugusman
Keyword(s):  
Clinical Trials ◽  
Natural Products ◽  
Matrix Metalloproteinases ◽  
Animal Studies ◽  
Current Knowledge ◽  
In Vitro Models ◽  
In Vivo Studies ◽  
Extracellular Matrix Components

: Matrix metalloproteinases (MMPs) are a group of zinc-dependent metallo-endopeptidase that are responsible towards the degradation, repair and remodelling of extracellular matrix components. MMPs play an important role in maintaining a normal physiological function and preventing diseases such as cancer and cardiovascular diseases. Natural products derived from plants have been used as traditional medicine for centuries. Its active compounds, such as catechin, resveratrol and quercetin, are suggested to play an important role as MMPs inhibitors, thereby opening new insights into their applications in many fields, such as pharmaceutical, cosmetic and food industries. This review summarises the current knowledge on plant-derived natural products with MMP-modulating activities. Most of the reviewed plant-derived products exhibit an inhibitory activity on MMPs. Amongst MMPs, MMP-2 and MMP-9 are the most studied. The expression of MMPs is inhibited through respective signalling pathways, such as MAPK, NF-κB and PI3 kinase pathways, which contribute to the reduction in cancer cell behaviours, such as proliferation and migration. Most studies have employed in vitro models, but a limited number of animal studies and clinical trials have been conducted. Even though plant-derived products show promising results in modulating MMPs, more in vivo studies and clinical trials are needed to support their therapeutic applications in the future.

Biological NMR Spectroscopy

1997 ◽  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
State Of The Art ◽  
Critical Assessment ◽  
Resonance Spectroscopy ◽  
History Of ◽  
Structure Of Proteins

This book presents a critical assessment of progress on the use of nuclear magnetic resonance spectroscopy to determine the structure of proteins, including brief reviews of the history of the field along with coverage of current clinical and in vivo applications. The book, in honor of Oleg Jardetsky, one of the pioneers of the field, is edited by two of the most highly respected investigators using NMR, and features contributions by most of the leading workers in the field. It will be valued as a landmark publication that presents the state-of-the-art perspectives regarding one of today's most important technologies.

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