scholarly journals A Behavioral Survey of the Effects of Kavalactones on Caenorhabditis elegans Neuromuscular Transmission

2017 ◽  
Vol 11 ◽  
pp. 117906951770538 ◽  
Author(s):  
Bwarenaba B Kautu ◽  
Juliana Phillips ◽  
Kellie Steele ◽  
M Shawn Mengarelli ◽  
Eric A Nord

Kava is a plant root extract that is widely consumed by Pacific Islanders. Kava contains a class of lactone compounds called kavalactones. The sedative and anxiolytic effects of kava are likely attributed to the efficacies of kavalactones on the nervous system. Although some studies have implicated the potencies of certain kavalactone species on γ-aminobutyric acid transmission, evidence supporting the action of kavalactones on the eukaryotic neuromuscular junction (NMJ) and acetylcholine (ACh) transmission is scant. Here, we used behavioral assays to demonstrate the effects of kavalactones at the Caenorhabditis elegans NMJ. Our results suggest that kavalactones disrupt the inhibitory-excitatory balance at the NMJ. Such perturbation of NMJ activity is likely due to excess or prolonged ACh transmission. In addition, we found that kavain, a major constituent of kava, induced worm paralysis but not convulsions. Hence, the modulatory action of kavain could be distinct from the other kavalactone species.

2021 ◽  
Vol 8 (3) ◽  
Author(s):  
K N Jiji ◽  
P Muralidharan

Medicinal plants act as a vital source in improving health and overcoming the side effects of modern-day medicine. Many evidence-based reports are present in the literature about the benefits of medicinal plants. Clitoria ternatea L. belongs to the family Fabaceae and is known to be one of the important Ayurvedic medicinal plant whose uses are specified mainly for the modification of nervous system activities. ‘Medhyarasayana’ is one of the Ayurvedic formulations which is used to promote the intellectual capacity, revive the body and nervous tissue, Clitoria ternatea serves as a major constituent of ‘Medhyarasayana.’ Identification and characterization of active metabolites of C. ternatea will help to isolate the important phytoconstituents responsible for the central nervous system effects, isolated components can be utilized in future for the formulation of new medicine for various neurodegenerative disorders. In the present study, the phytochemical evaluation of the ethanolic root extract of C. ternatea (EECT) was performed using the HR-LCMS technique. Preliminary qualitative phytoconstituents analysis showed the presence of tannins, alkaloids, saponins, steroids, carbohydrate, protein, flavonoids and triterpenoids in the ethanolic root extract. Almost 42 compounds were identified when the EECT subjected to HR-LCMS analysis.


2019 ◽  
Vol 20 (16) ◽  
pp. 3854 ◽  
Author(s):  
Tae-Geun Kil ◽  
Su-Hwan Kang ◽  
Tae-Hun Kim ◽  
Kyung-Chul Shin ◽  
Deok-Kun Oh

Platycodin D (PD), a major saponin (platycoside) in Platycodi radix (balloon flower root), has higher pharmacological activity than the other major platycosides; however, its content in the plant root is only approximately 10% (w/w) and the productivities of PD by several enzymes are still too low for industrial applications. To rapidly increase the total PD content, the β-glucosidase from Caldicellulosiruptor bescii was used for the deglucosylation of the PD precursors platycoside E (PE) and platycodin D3 (PD3) in the root extract into PD. Under the optimized reaction conditions, the enzyme completely converted the PD precursors into PD with the highest productivity reported so far, increasing the total PD content to 48% (w/w). In the biotransformation process, the platycosides in Platycodi radix were hydrolyzed by four pathways: deapiosylated (deapi)-PE → deapi-PD3 → deapi-PD, PE → PD3 → PD, polygalacin D3 → polygalacin D, and 3″-O-acetyl polygalacin D3 → 3″-O-acetyl polygalacin D.


1993 ◽  
Vol 175 (1) ◽  
pp. 283-297 ◽  
Author(s):  
L. Avery

1. Previous work has shown that 12 of the 14 types of neurons in the Caenorhabditis elegans pharyngeal nervous system are collectively but not individually necessary for the trapping and transport of bacteria. The aim of these experiments was to determine the functions of individual neuron types by laser-killing combinations of neurons and looking at the effects on behavior. 2. The motor neuron M3 and the sensory neuron I5 are important in trapping bacteria, as shown by two observations. First, when M3 and I5 are both killed, trapping is inefficient in the isthmus (the middle section of the pharynx). Second, M3 is sufficient in the absence of the other 11 neuron types for normal trapping in the corpus (anterior pharynx). 3. M3 and I5 influence the timing of pharyngeal muscle motions. When M3 is killed, pump duration (the interval from the beginning of pharyngeal contraction to the end of relaxation) increases from 170 to 196 ms. This increase is at least partially due to a slower relaxation. Thus, M3 speeds up relaxation. Pump duration decreases to 159 ms when I5 is killed. When I5 and M3 are both killed, pump durations are long (192 ms), just as when M3 alone is killed. These observations, together with previous electron microscopic work showing synapses from I5 to M3, suggest that I5 slows down relaxation by inhibiting M3. 4. To explain these results, I propose that M3 and I5 promote bacterial trapping by regulating the relative timing of muscle relaxation in different regions of the pharynx.


1977 ◽  
Vol 40 (2) ◽  
pp. 453-460 ◽  
Author(s):  
P. B. Sargent

1. A study was made of the synthesis of acetylcholine (ACh) and other transmitters by the cell bodies of functionally identified neurons in leech segmental ganglia. 2. Choline acetyltransferase, the synthetic enzyme for ACh, was detected in excitatory motoneurons but not in mechanosensory cells or Retzius cells. The ability of motoneurons to synthesize ACh was also demonstrated by their accumulation of [3H]ACh following incubation of segmental ganglia with [3H]choline. [3H]ACh was not detected in the other cell types. When eserine was included in [3H]choline incubations, the amount of [3H]ACh in motoneurons increased severalfold and small amounts of [3H]ACh (1% that in motor cells) appeared in extracts of sensory and Retzius cells. 3. In addition to [3H]ACh segmental ganglia synthesized [3H]5-HT, [3H]gamma-aminobutyric acid, [3H]dopamine, and [3H]octopamine from exogenous, labeled precursors. None of these labeled transmitters was detected in identified neurons except [3H]5-HT, which was found in Retzius cells. 4. These results provide biochemical evidence that excitatory motoneurons in the leech are cholinergic, but leave open the identity of the sensory transmitter(s).


2013 ◽  
Vol 14 (4) ◽  
pp. 393-398

The occurrence of trihalomethanes (THMs) was studied in the drinking water samples from urban water supply network of Karachi city that served more than 18 million people. Drinking water samples were collected from 58 locations in summer (May-August) and winter (November-February) seasons. The major constituent of THMs detected was chloroform in winter (92.34%) and summer (93.07%), while the other THMs determined at lower concentrations. Summer and winter concentrations of total THMs at places exceed the levels regulated by UEPA (80 μg l-1) and WHO (100 μg l-1). GIS linked temporal variability in two seasons showed significantly higher median concentration (2.5%-23.06%) of THMs compared to winter.


Genetics ◽  
1988 ◽  
Vol 120 (4) ◽  
pp. 977-986
Author(s):  
K J Kemphues ◽  
M Kusch ◽  
N Wolf

Abstract We have analyzed a set of linkage group (LG) II maternal-effect lethal mutations in Caenorhabditis elegans isolated by a new screening procedure. Screens of 12,455 F1 progeny from mutagenized adults resulted in the recovery of 54 maternal-effect lethal mutations identifying 29 genes. Of the 54 mutations, 39 are strict maternal-effect mutations defining 17 genes. These 17 genes fall into two classes distinguished by frequency of mutation to strict maternal-effect lethality. The smaller class, comprised of four genes, mutated to strict maternal-effect lethality at a frequency close to 5 X 10(-4), a rate typical of essential genes in C. elegans. Two of these genes are expressed during oogenesis and required exclusively for embryogenesis (pure maternal genes), one appears to be required specifically for meiosis, and the fourth has a more complex pattern of expression. The other 13 genes were represented by only one or two strict maternal alleles each. Two of these are identical genes previously identified by nonmaternal embryonic lethal mutations. We interpret our results to mean that although many C. elegans genes can mutate to strict maternal-effect lethality, most genes mutate to that phenotype rarely. Pure maternal genes, however, are among a smaller class of genes that mutate to maternal-effect lethality at typical rates. If our interpretation is correct, we are near saturation for pure maternal genes in the region of LG II balanced by mnC1. We conclude that the number of pure maternal genes in C. elegans is small, being probably not much higher than 12.


2020 ◽  
Vol 2 (Supplement_3) ◽  
pp. ii18-ii18
Author(s):  
Kiyonori Kuwahara ◽  
Shigeo Ohba ◽  
Kazuyasu Matsumura ◽  
Saeko Higashiguchi ◽  
Daijiro Kojima ◽  
...  

Abstract Background: Although high dose-methotrexate therapy has been performed for primary central nervous system malignant lymphoma (PCNSL), R-MPV (rituximab, methotrexate (MTX), procarbazine and vincristine) therapy is currently the first line therapy for (PCNSL) in our hospital. This study examines the results of R-MPV therapy comparing with past treatment. Method/Subjects: Thirty-seven patients treated at our hospital from 2009 to 2020 were included. Overall survival time, progression free survival time, and toxicities were evaluated. Results: The average age of patients was 65.7 years. Patients included 21 males and 16 females. Thirty-six patients were diagnosed DLBCL by resected brain tumor tissues, and one was diagnosed DLBCL by vitreous biopsy. As initial treatment, rituximab±HD-MTX therapy (R±MTX group) was performed in 20 cases, HD-MTX therapy plus radiation (R±MTX+RT group) was performed in 12 cases, and RMPV therapy was performed in 5 cases (R-MPV group). Median OS of all cases was 69 months and median PFS was 38 months. Median OS was 69 months in R±MTX group and could not be calculated in R±MTX+RT, and R-MPV groups. Median PFS was 16 months and 56 months in R±MTX group and R±MTX+RT, respectively, and could not be calculated in the R-MPV group. Although the R-MPV group had a short follow-up period, the results were considered to be comparable to those of the R±MTX+RT group. On the other hand, grade 3/4 adverse events occurred in 50%, 25%, and 100%, respectively. Conclusion: R-MPV therapy may delay the timing of radiation and reduce the amount of radiation. On the other hand, the frequency of adverse events is high, and more strict management of treatment is required.


1957 ◽  
Vol 188 (2) ◽  
pp. 371-374 ◽  
Author(s):  
Sol Rothman ◽  
Douglas R. Drury

The blood pressure responses to various drugs were investigated in renal hypertensive, cerebral hypertensive and normotensive rabbits. Hexamethonium bromide and Dibenamine reduced the blood pressures of renal and cerebral hypertensives. Effects in the normal were insignificant. The cerebral hypertensive's blood pressure was slightly affected by benzodioxane. Blood pressure was not reduced at all in the other groups. Blood pressure of the renal hypertensive rabbit was greatly reduced by Veriloid and dihydroergocornine. Blood pressures of cerebral and normal animals were affected to a lesser degree. The results suggest that maintenance of hypertension in the cerebral hypertensive rabbit depends on an overactive sympathetic nervous system, possibly due to the release of medullary pressor centers from inhibitory impulses originating in higher centers; whereas, the maintenance of hypertension in the renal hypertensive rabbit may be attributed to an increased reactivity of the peripheral vasculature to a normal sympathetic tone.


1996 ◽  
Vol 85 (4) ◽  
pp. 901-912 ◽  
Author(s):  
Michael C. Crowder ◽  
Laynie D. Shebester ◽  
Tim Schedl

Background The nematode Caenorhabditis elegans offers many advantages as a model organism for studying volatile anesthetic actions. It has a simple, well-understood nervous system; it allows the researcher to do forward genetics; and its genome will soon be completely sequenced. C. elegans is immobilized by volatile anesthetics only at high concentrations and with an unusually slow time course. Here other behavioral dysfunctions are considered as anesthetic endpoints in C. elegans. Methods The potency of halothane for disrupting eight different behaviors was determined by logistic regression of concentration and response data. Other volatile anesthetics were also tested for some behaviors. Established protocols were used for behavioral endpoints that, except for pharyngeal pumping, were set as complete disruption of the behavior. Time courses were measured for rapid behaviors. Recovery from exposure to 1 or 4 vol% halothane was determined for mating, chemotaxis, and gross movement. All experiments were performed at 20 to 22 degrees C. Results The median effective concentration values for halothane inhibition of mating (0.30 vol%-0.21 mM), chemotaxis (0.34 vol%-0.24 mM), and coordinated movement (0.32 vol% - 0.23 mM) were similar to the human minimum alveolar concentration (MAC; 0.21 mM). In contrast, halothane produced immobility with a median effective concentration of 3.65 vol% (2.6 mM). Other behaviors had intermediate sensitivities. Halothane's effects reached steady-state in 10 min for all behaviors tested except immobility, which required 2 h. Recovery was complete after exposure to 1 vol% halothane but was significantly reduced after exposure to immobilizing concentrations. Conclusions Volatile anesthetics selectively disrupt C. elegans behavior. The potency, time course, and recovery characteristics of halothane's effects on three behaviors are similar to its anesthetic properties in vertebrates. The affected nervous system molecules may express structural motifs similar to those on vertebrate anesthetic targets.


2010 ◽  
Vol 38 (1) ◽  
pp. 172-176 ◽  
Author(s):  
Jeff W. Barclay ◽  
Margaret E. Graham ◽  
Mark R. Edwards ◽  
James R. Johnson ◽  
Alan Morgan ◽  
...  

Acute exposure to ethanol is known to modulate signalling within the nervous system. Physiologically these effects are both presynaptic and postsynaptic in origin; however, considerably more research has focused primarily on postsynaptic targets. Recent research using the model organism Caenorhabditis elegans has determined a role for specific proteins (Munc18-1 and Rab3) and processes (synaptic vesicle recruitment and fusion) in transducing the presynaptic effects of ethanol. In the present paper, we review these results, identifying the proteins and protein interactions involved in ethanol sensitivity and discuss their links with mammalian studies of alcohol abuse.


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