Munasinghe, M. et al. (2019) International Worm Meeting "Cocoa reduces Amyloid-beta toxicity and increases lifespan in a transgenic Caenorhabditis elegans."

Kolivas, D., Munasinghe, M., Thomas, J., Almotayri, A., Jois, M.

[International Worm Meeting, 2019]

Alzheimer's disease (AD) is a progressive neurodegenerative disorder and is the most common cause of dementia worldwide. Amyloid-? (A?) induced oxidative stress and toxicity are believed to be behind the pathogenesis of AD. Currently there is no pharmaceutical intervention that has been shown to cure or treat AD. Polyphenol rich food are of great interest in both nutrition and medicine for their potential to improve human health. In particular, the consumption of flavonoid rich cocoa is reported to have several health-promoting effects relating to its antioxidant capacity, which include reducing the risk for cardiovascular disease, cancer, and protection against neurotoxicity. The objective of this study was to determine the long-term effects of cocoa supplementation on A? toxicity in a transgenic model of C. elegans. Control (GRU101) and the transgenic strain (GRU102) expressing constitutive pan-neuronal A?1-42 were grown on Nematode Growth Medium (NGM) plates with Escherichia coli (E. coli) OP50 diet. Cocoa powder suspended in M9 buffer (5mg/ml for motility assay and 1mg/ml, 2 mg/ml and 3mg/ml for lifespan assay) was spread on the lawn of E. coli. Measurements included growth, motility and lifespan. GRU102 strain exhibited a lower growth rate, reduced motility and a 13% reduction in mean lifespan. Cocoa supplementation increased growth rate and increased motility of GRU102 strain to reach similar levels to the GRU101 strain. In addition, cocoa supplementation increased the lifespan of GRU102 in a dose dependent manner. Cocoa supplementation appears to reverse the symptoms relating to A? toxicity in GRU102 worms.

Munasinghe M et al. (2021) Nutr Metab Insights "Early Exposure is Necessary for the Lifespan Extension Effects of Cocoa in C. elegans."

Thomas J, Almotayri A, Munasinghe M, Heydarian D, Jois M

[Nutr Metab Insights, 2021]

Background: when supplemented starting from L1 stage. Aim: . Methods: were supplemented with cocoa starting from L1 stage till the death. Survival curves were plotted, and mean lifespan was reported. Results: mutants. Conclusion: Early-start supplementation is essential for cocoa-mediated lifespan extension which is dependent on insulin/IGF-1 signaling pathway and mitochondrial respiration.

Almotayri A et al. (2021) Curr Aging Sci "The Effect of Mianserin on Lifespan of Caenorhabditis elegans is Abolished by Glucose."

Jois M, Thomas J, Munasinghe M, Almotayri A

[Curr Aging Sci, 2021]

BACKGROUND: The antidepressant mianserin has been shown to extend the lifespan of Caenorhabditis elegans (C. elegans), a well-established model organism used in aging research. The extension of lifespan in C. elegans was shown to be dependent on increased expression of the scaffolding protein (ANK3/unc-44). In contrast, antidepressant use in humans is associated with an increased risk of death. The C. elegans in the laboratory are fed Escherichia coli (E. coli), a diet high in protein and low in carbohydrate, whereas a typical human diet is high in carbohydrates. We hypothesized that dietary carbohydrates might mitigate the lifespan-extension effect of mianserin. OBJECTIVE: To investigate the effect of glucose added to the diet of C. elegans on the lifespan-extension effect of mianserin. METHODS: Wild-type Bristol N2 and ANK3/unc-44 inactivating mutants were cultured on agar plates containing nematode growth medium and fed E. coli. Treatment groups included (C) control, (M50) 50 M mianserin, (G) 73 mM glucose, and (M50G) 50 M mianserin and 73 mM glucose. Lifespan was determined by monitoring the worms until they died. Statistical analysis was performed using the Kaplan-Meier version of the log-rank test. RESULTS: Mianserin treatment resulted in a 12% increase in lifespan (P<0.05) of wild-type Bristol N2 worms but reduced lifespan by 6% in ANK3/unc-44 mutants, consistent with previous research. The addition of glucose to the diet reduced the lifespan of both strains of worms and abolished the lifespan-extension by mianserin. CONCLUSION: The addition of glucose to the diet of C. elegans abolishes the lifespan-extension effects of mianserin.

Thomas, J. et al. (2019) International Worm Meeting "Effect of mianserin on the lifespan of Caenorhabditis elegansis is affected by the time of exposure and glucose supplementation."

Jois, M., Almotyari, A., Thomas, J., Munasinghe, M.

[International Worm Meeting, 2019]

Mianserin is a serotonin receptor antagonist, used in the treatment of depression. Its effect on lifespan has been controversial with both an extension as well as a reduction of the lifespan of C elegans reported previously. Addition of glucose to the culture medium has also been shown to reduce lifespan. The aim of the present study was to investigate whether the time of exposure and the addition of glucose affected the mianserin's effect on lifespan. Wild-type Bristol N2 strain (Caenorhabditis Genetics Centre) were grown on NGM plates seeded with E. coli (OP50). Mianserin (50 M) and glucose (5%) were added to the NGM at L1 or adult (day 5) stage of the worm growth. Treatment of mianserin at the L1 stage, significantly reduced lifespan (12.26 plus or minus 0.34) as compared to control group (21.69 plus or minus 0.18). However, the addition of glucose to the mianserin showed a significant improvement in lifespan (18.6 plus or minus 0.17). Treatment of mianserin on day 5 increased the lifespan (22.47 plus or minus 0.27) as compared to the combination of glucose and mianserin (19.12 plus or minus 0.12). Addition of glucose reversed the reduction (L1 treatment) as well as the extension of lifespan (adult treatment) by mianserin. In conclusion, the effect of mianserin on lifespan is affected by the time of exposure and the addition of glucose.

Wypijewska A et al. (2012) Biochemistry "7-methylguanosine diphosphate (m(7)GDP) is not hydrolyzed but strongly bound by decapping scavenger (DcpS) enzymes and potently inhibits their activity."

Wypijewska A, Darzynkiewicz E, Davis RE, Jemielity J, Bojarska E, Lukaszewicz M, Stepinski J

[Biochemistry, 2012]

Decapping scavenger (DcpS) enzymes catalyze the cleavage of a residual cap structure following 3' 5' mRNA decay. Some previous studies suggested that both m(7)GpppG and m(7)GDP were substrates for DcpS hydrolysis. Herein, we show that mononucleoside diphosphates, m(7)GDP (7-methylguanosine diphosphate) and m(3)(2,2,7)GDP (2,2,7-trimethylguanosine diphosphate), resulting from mRNA decapping by the Dcp1/2 complex in the 5' 3' mRNA decay, are not degraded by recombinant DcpS proteins (human, nematode, and yeast). Furthermore, whereas mononucleoside diphosphates (m(7)GDP and m(3)(2,2,7)GDP) are not hydrolyzed by DcpS, mononucleoside triphosphates (m(7)GTP and m(3)(2,2,7)GTP) are, demonstrating the importance of a triphosphate chain for DcpS hydrolytic activity. m(7)GTP and m(3)(2,2,7)GTP are cleaved at a slower rate than their corresponding dinucleotides (m(7)GpppG and m(3)(2,2,7)GpppG, respectively), indicating an involvement of the second nucleoside for efficient DcpS-mediated digestion. Although DcpS enzymes cannot hydrolyze m(7)GDP, they have a high binding affinity for m(7)GDP and m(7)GDP potently inhibits DcpS hydrolysis of m(7)GpppG, suggesting that m(7)GDP may function as an efficient DcpS inhibitor. Our data have important implications for the regulatory role of m(7)GDP in mRNA metabolic pathways due to its possible interactions with different cap-binding proteins, such as DcpS or eIF4E.

O'Connell EM et al. (2015) J Infect Dis "Targeting Filarial Abl-like Kinases: Orally Available, Food and Drug Administration-Approved Tyrosine Kinase Inhibitors Are Microfilaricidal and Macrofilaricidal."

Nutman TB, O'Connell EM, Bennuru S, Steel C, Dolan MA

[J Infect Dis, 2015]

BACKGROUND: Elimination of onchocerciasis and lymphatic filariasis is targeted for 2020. Given the coincident Loa loa infections in Central Africa and the potential for drug resistance development, the need for new microfilaricides and macrofilaricides has never been greater. With the genomes of L. loa, Onchocerca volvulus, Wuchereria bancrofti, and Brugia malayi available, new drug targets have been identified. METHODS: The effects of the tyrosine kinase inhibitors imatinib, nilotinib, and dasatinib on B. malayi adult males, adult females, L3 larvae, and microfilariae were assessed using a wide dose range (0-100 M) in vitro. RESULTS: For microfilariae, median inhibitory concentrations (IC50 values) on day 6 were 6.06 M for imatinib, 3.72 M for dasatinib, and 81.35 M for nilotinib; for L3 larvae, 11.27 M, 13.64 M, and 70.98 M, respectively; for adult males, 41.6 M, 3.87 M, and 68.22 M, respectively; and for adult females, 42.89 M, 9.8 M, and >100 M, respectively. Three-dimensional modeling suggests how these tyrosine kinase inhibitors bind and inhibit filarial protein activity. CONCLUSIONS: Given the safety of imatinib in humans, plans are underway for pilot clinical trials to assess its efficacy in patients with filarial infections.

Almotayri, A. et al. (2019) International Worm Meeting "Culinary spices reduce the body fat content of Caenorhabditis elegans."

Thomas, J., Almotayri, A., Jois, M., Munasinghe, M.

[International Worm Meeting, 2019]

Oxidative stress and inflammation are critical components in the development of obesity. Culinary herbs and spices, abundant in anti-oxidant and anti-inflammatory phytochemicals, may be useful in the prevention of obesity. In the present study, we report strong anti-obesity properties of culinary spices. Wild-type Bristol N2 strain (Caenorhabditis Genetics Centre) were grown on NGM plates seeded with E. coli (OP50). Worms were exposed to extract (1mg of dry powder per 1ml of NGM) of red chilli, black pepper, ginger, and turmeric. Fat content was determined on day 5 (adult stage) by staining with Oil-Red O. Compared to control group, chilli, ginger and pepper reduced the fat content of the worms by 92, 89 and 57% respectively. Turmeric had no effect on the fat content of C elegans. In conclusion, culinary herbs and spices may be useful in the prevention of obesity and C. elegans is a useful model for screening the anti-obesity properties of culinary spices.

Wood WB (1976) Worm Breeder's Gazette "maternal effects among ts zygote-defective (zyg) mutants."

Wood WB

[Worm Breeder's Gazette, 1976]

We have studied maternal effects in 23 zyg ts mutants to estimate the times of expression of genes whose products are required in embryogenesis. We have used the following three tests, called arbitrarily A, B, and C. A test: Heterozygous (m/+) L4's are shifted to 25 C and allowed to self-fertilize. If 100% of their eggs yield larvae (25% of which express the mutant phenotype as adults), then the mutant is scored as maternal (M). If 25% of the F1 eggs fail to hatch, then the mutant is scored as non-maternal (N). An M result indicates that expression of the + allele in the parent allows m/m zygotes to hatch and grow to adulthood. A result of N indicates the opposite: that the + allele must be expressed in the zygote for hatching to occur. Out of 23 zyg mutants tested, 3 were scored N and 20 were scored M in the A test. Therefore, for most of the genes defined by these mutants, expression in the parent is sufficient for zygote survival, even if the gene is not expressed in the zygote. B test: Homozygous (m/m) hermaphrodites reared at 25 C are mated with N2 (+/+) males. If eggs fail to hatch at 25 C, but mated hermaphrodites shifted to 16 C produce cross progeny to give proof of mating, then the mutant is scored M. If cross progeny appear in the 25 C mating, then the mutant is scored N. An M result indicates that expression of the + allele in the zygote is not sufficient to allow m/+ progeny of an m/m hermaphrodite to survive. Conversely an N result indicates either that zygotic expression of the + allele is sufficient for survival, or that a sperm function or factor needed for early embryogenesis can be supplied paternally (see C test below). Out of the 23 zyg mutants tested, 11 were scored M and 12 were scored N. The combined results of A and B tests and their simplest interpretation are as follows. Ten mutants are M,M; the genes defined by these mutants must be expressed in the hermaphrodite parent for the zygote to survive. Ten mutants are M,N; these genes can be expressed either in the parent or in the zygote. Two mutants are N,N; these genes must be expressed in the zygote. One mutant is N,M; this gene must be expressed both in the maternal parent and in the zygote. C test: Homozygous (m/m) hermaphrodites reared at 25 C are mated with heterozygous (m/+) males. If rescue by a +/+ male in the B test depends on the + allele, then only half the cross progeny zygotes of a C test mating (m/+ male x m/m hermaphrodite) should survive. However, if rescue depends on a function or cytoplasmic component from the male sperm, then all the cross progeny zygotes in a C test should survive. Of the 10 M,N mutants, 6 have been C tested; one exhibited paternal rescue independent of the + allele. The A and B tests also were carried out on 16 mutants that arrest before the L3 molt (acc mutants). In the A test on 2 of these mutants, all m/m progeny of m/+ parents grew to adulthood at 25 C. Therefore, parental contributions are sufficient to overcome a progeny mutational block as late as the L2 stage. All 16 acc mutants scored N in the B test.

Ali Khan L et al. (1994) Worm Breeder's Gazette "cej-1 Encodes a Novel Protein With Poly-Threonine Motif"

Siddiqui SS, Fukushige T, Ali Khan L, Tsukita Sh, Tabish M, Itoh M

[Worm Breeder's Gazette, 1994]

cej-1 Encodes a Novel Protein with Poly-Threonine Motif M. L. A. Khanl, M. Tabish, T. Fukushigel1 S. Tsukita2, M. Itoh , Sh. Tsukita , and S. S. Siddiqui. (1): Lab. of Molecular Biology, Dept of Ecological Engg. Toyohashi Univ. Technology, Toyohashi 441, and (2). National Institute for Physiological Sciences, Okazaki 444, Japan.

Lemire BD et al. (2009) Mech Ageing Dev "C. elegans longevity pathways converge to decrease mitochondrial membrane potential."

Behrendt M, Decorby A, Lemire BD, Gaskova D

[Mech Ageing Dev, 2009]

Energy production via oxidative phosphorylation generates a mitochondrial membrane potential (DeltaPsi(m)) across the inner membrane. In this work, we show that a lower DeltaPsi(m) is associated with increased lifespan in Caenorhabditis elegans. The long-lived mutants daf-2(e1370), age-1(hx546), clk-1(qm30), isp-1(qm150) and eat-2(ad465) all have a lower DeltaPsi(m) than wild type animals. The lower DeltaPsi(m) of daf-2(e1370) is daf-16 dependent, indicating that the insulin-like signaling pathway not only regulates lifespan but also mitochondrial energetics. RNA interference (RNAi) against 17 genes shown to extend lifespan also decrease DeltaPsi(m). Furthermore, lifespan can be significantly extended with the uncoupler carbonylcyanide-3-chlorophenylhydrazone (CCCP), which dissipates DeltaPsi(m). We conclude that longevity pathways converge on the mitochondria and lead to a decreased DeltaPsi(m). Our results are consistent with the 'uncoupling to survive' hypothesis, which states that dissipation of the DeltaPsi(m) will extend lifespan.