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Jamai D, Kallel I, Mekrazi S, Aloulou S, Walha M, Selmi B, Khabir A. Combined expression of HIF1α, VEGF and HER2 predicts metastasis, relapse and response to combination chemotherapy in colorectal cancer patients. Ann Diagn Pathol 2023; 66:152168. [PMID: 37290395 DOI: 10.1016/j.anndiagpath.2023.152168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2023] [Revised: 05/19/2023] [Accepted: 05/23/2023] [Indexed: 06/10/2023]
Abstract
Addressing a single target is the frequent development of drug resistance followed by cancer relapse and treatment failure. Therefore, assessment of simultaneous expression of target molecules is essential to choose the optimal combination therapy for each colorectal cancer patient. This study aims to evaluate the immunohistochemical expression of HIF1α, HER2 and VEGF and to clarify their clinical significance as prognostic factors and predictive markers of FOLFOX (combination chemotherapy inclusive of Leucovorin calcium, Fluorouracil and Oxaliplatin response). Marker expression was retrospectively evaluated by immunohistochemistry in 111 patients with colorectal adenocarcinomas from south Tunisia, followed by statistical analysis. The immunohistochemical staining revealed that 45 %, 80.2 %, 86.5 % and 25.5 % of specimen were positive for nuclear, cytoplasmic HIF1α expression, VEGF and HER2 respectively. Nuclear HIF1α and VEGF were associated with worst prognosis while cytoplasmic HIF1α and HER2 were correlated with favourable prognosis. Multivariate analysis confirms the association between nuclear HIF1α, distant metastasis, relapse, FOLFOX response and 5 years overall survival. HIF1α positivity and HER2 negativity were significantly associated to short survival. Combined immunoprofiles HIF1α+/VEGF+, HIF1α+/HER2-, HIF1α+/VEGF+/HER2- were associated to distant metastasis, cancer relapse and short survival. Interestingly, our findings confirmed that patients bearing a HIF1α positive tumor were significantly more resistant to FOLFOX compared to negative ones (p = 0.002, p ≤ 0.001). Positive expression of HIF1α and VEGF, or decreased expression of HER2 was each associated with poor prognosis and short overall survival. In summary, we found that expression of nuclear HIF1α, alone or combined with VEGF and HER2 serves as a predictive marker of poor prognosis and FOLFOX response in colorectal cancer from south Tunisia.
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Affiliation(s)
- Dhouha Jamai
- Research Laboratory of Bioresources, Integrative Biology and Valorization LR14ES06, Higher Institute of Biotechnology of Monastir, University of Monastir, Avenue Tahar Hadded, BP 74, 5000 Monastir, Tunisia.
| | - Imen Kallel
- Research Laboratory of Toxicology, Microbiology, Environmental and Health LR17ES06, Faculty of Sciences of Sfax, University of Sfax, Tunisia
| | - Saoussen Mekrazi
- Research Laboratory of Toxicology, Microbiology, Environmental and Health LR17ES06, Faculty of Sciences of Sfax, University of Sfax, Tunisia
| | - Samir Aloulou
- Medical Oncology Service, Mohamed Ben Sassi University Hospital, Gabes, Tunisia
| | - Marwa Walha
- Department of Pathology, Habib Bourguiba University Hospital, Medenine, Tunisia
| | - Boulbaba Selmi
- Research Laboratory of Bioresources, Integrative Biology and Valorization LR14ES06, Higher Institute of Biotechnology of Monastir, University of Monastir, Avenue Tahar Hadded, BP 74, 5000 Monastir, Tunisia
| | - Abdelmajid Khabir
- Department of Pathology, Habib Bourguiba University Hospital, Medenine, Tunisia
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Jamai D, Gargouri R, Selmi B, Khabir A. ERCC1 and MGMT Methylation as a Predictive Marker of Relapse and FOLFOX Response in Colorectal Cancer Patients from South Tunisia. Genes (Basel) 2023; 14:1467. [PMID: 37510370 PMCID: PMC10379058 DOI: 10.3390/genes14071467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 06/20/2023] [Accepted: 07/14/2023] [Indexed: 07/30/2023] Open
Abstract
Genetic and epigenetic modifications present a major cause of relapse and treatment failure in colorectal cancer. This study aims to appreciate the prognostic and predictive value of ERRC1 and MGMT methylation. We also studied the prognostic impact of the ERCC1 rs11615 polymorphism as well as its expression. Methylation profiles of ERCC1 and MGMT were tested by methylation-specific PCR. A polymorphism of ERCC1 was studied using PCR-RFLP and its expression was examined by immunohistochemistry. ERCC1 was methylated in 44.6% of colorectal adenocarcinoma while MGMT was methylated in 69% of cases. MGMT methylation was strongly associated with lymph node metastasis, lymph invasion, venous invasion, perineural invasion, distant metastasis and relapse. Patients with methylation of both genes were more likely to have a poor prognosis and display chemoresistance. IHC analysis revealed that ERCC1 staining was noted in 52.8% of colorectal adenocarcinoma and inversely related to distant metastasis and cancer recurrence. Kaplan Meier analysis revealed that the worst overall survival was significantly associated with ERCC1 and MGMT methylation while decreased ERCC1 expression and T/T genotype exhibited the best overall survival. The methylation of MGMT, alone or combined with ERCC1, is predictive for poor prognosis, short overall survival and chemotherapy response in colorectal cancer.
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Affiliation(s)
- Dhouha Jamai
- Research Laboratory of Bioresources, Integrative Biology and Valorization LR14ES06, Higher Institute of Biotechnology of Monastir, University of Monastir, Avenue Tahar Haaadded, BP 74, Monastir 5000, Tunisia
- Department of Pathology, Habib Bourguiba University Hospital, Medenine 4100, Tunisia
| | - Raja Gargouri
- Laboratory of Molecular Biotechnology of Eukaryotes, Biotechnology Center, University of Sfax, Avenue Sidi Mansour, Sfax 3018, Tunisia
| | - Boulbaba Selmi
- Research Laboratory of Bioresources, Integrative Biology and Valorization LR14ES06, Higher Institute of Biotechnology of Monastir, University of Monastir, Avenue Tahar Haaadded, BP 74, Monastir 5000, Tunisia
| | - Abdelmajid Khabir
- Department of Pathology, Habib Bourguiba University Hospital, Medenine 4100, Tunisia
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Boujbiha MA, Chahdoura H, Adouni K, Ziani BEC, Snoussi M, Chakroun Y, Ciudad-Mulero M, Fernández-Ruiz V, Achour L, Selmi B, Morales P, Flamini G, Mosbah H. Wild Vitex agnus-castus L.: Phytochemical Characterization, Acute Toxicity, and Bioactive Properties. Molecules 2023; 28:5096. [PMID: 37446759 DOI: 10.3390/molecules28135096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 06/23/2023] [Accepted: 06/27/2023] [Indexed: 07/15/2023] Open
Abstract
Wild Vitex agnus-castus (VAC) is a Mediterranean plant that is rich in bioactive metabolites. This study aimed to validate, for the first time, the beneficial use of VAC fruits and fruit decoctions (VFDs) through in vitro and in vivo trials. Forty-one volatile components were detected in VAC fruits, with 1,8-cineole (30.3%) comprising the majority. The antioxidant activity of VFD was measured by using different in vitro methods (EC50 of 0.16 mg/mL by β-carotene bleaching inhibition assay) and by measuring the DNA protection power. Using the disc diffusion assay, the antimicrobial activity of VFD was evaluated, and it exhibited a noticeable anticandidal activity. VFD did not cause any toxicity or mortality in rats treated with doses > 200 mg/kg. Using the acetic acid writhing test, the antinociceptive activity of VFD was measured. Our results showed that VFD at 200 mg/kg exhibited a higher analgesic activity (81.68%) than acetylsalicylic acid used as a positive control (74.35%). Its gastroprotective ability was assessed by HCl/ethanol-induced gastric lesions, which were remarkably inhibited (84.62%) by intraperitoneal administration of VFD. This work helps to validate the popular use of VAC to treat nociceptive, inflammatory, and gastric disorders and encourages researchers to further investigate the identification of pharmacological compounds from this species.
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Affiliation(s)
- Mohamed Ali Boujbiha
- Laboratory of Bioresources: Integrative Biology and Exploiting, Higher Institute of Biotechnology of Monastir, University of Monastir, Avenue Taher Hadded BP 74, Monastir 5000, Tunisia
| | - Hassiba Chahdoura
- Unité de Recherche "Génomique, Biotechnologie et Stratégies Antivirales", Institut Supérieur de Biotechnologie, Université de Monastir, BP74, Avenue Tahar Hadded, Monastir 5000, Tunisia
| | - Khaoula Adouni
- Laboratory of Bioresources: Integrative Biology and Exploiting, Higher Institute of Biotechnology of Monastir, University of Monastir, Avenue Taher Hadded BP 74, Monastir 5000, Tunisia
| | | | - Mejdi Snoussi
- Department of Biology, University of Hail, Ha'il P.O. Box 81451, Saudi Arabia
- Laboratory of Genetics, Biodiversity and Valorisation of Bioresources, High Institute of Biotechnology-University of Monastir, Monastir 5000, Tunisia
| | - Yasmine Chakroun
- Laboratory of Bioresources: Integrative Biology and Exploiting, Higher Institute of Biotechnology of Monastir, University of Monastir, Avenue Taher Hadded BP 74, Monastir 5000, Tunisia
| | - María Ciudad-Mulero
- Department of Nutrition and Food Science, Faculty of Pharmacy, Complutense University of Madrid, Plaza Ramon y Cajal, s/n, E-28040 Madrid, Spain
| | - Virginia Fernández-Ruiz
- Department of Nutrition and Food Science, Faculty of Pharmacy, Complutense University of Madrid, Plaza Ramon y Cajal, s/n, E-28040 Madrid, Spain
| | - Lotfi Achour
- Laboratory of Bioresources: Integrative Biology and Exploiting, Higher Institute of Biotechnology of Monastir, University of Monastir, Avenue Taher Hadded BP 74, Monastir 5000, Tunisia
| | - Boulbaba Selmi
- Laboratory of Bioresources: Integrative Biology and Exploiting, Higher Institute of Biotechnology of Monastir, University of Monastir, Avenue Taher Hadded BP 74, Monastir 5000, Tunisia
| | - Patricia Morales
- Department of Nutrition and Food Science, Faculty of Pharmacy, Complutense University of Madrid, Plaza Ramon y Cajal, s/n, E-28040 Madrid, Spain
| | - Guido Flamini
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno 6, 56126 Pisa, Italy
- Centro Interdipartimentale di Ricerca "Nutraceutica e Alimentazione per la Salute", Università di Pisa, Via del Borghetto 80, 56124 Pisa, Italy
| | - Habib Mosbah
- Laboratory of Bioresources: Integrative Biology and Exploiting, Higher Institute of Biotechnology of Monastir, University of Monastir, Avenue Taher Hadded BP 74, Monastir 5000, Tunisia
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Daoudi H, Bouafia A, Meneceur S, Laouini SE, Belkhalfa H, Lebbihi R, Selmi B. Secondary Metabolite from Nigella Sativa Seeds Mediated Synthesis of Silver Oxide Nanoparticles for Efficient Antioxidant and Antibacterial Activity. J Inorg Organomet Polym Mater 2022. [DOI: 10.1007/s10904-022-02393-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Kouidhi S, Mnif W, Alqarni N, Abdelwahed S, Redissi A, Ammous N, Selmi B, Gargouri A, Achour S, Cherif A, Mosbah A. Design and use of chimeric peptides in a new non-destructive ecological process applied to the extraction of all trans/9-cis β-carotene isomers from Dunaliella salina. Food Sci Nutr 2022; 10:1928-1936. [PMID: 35702303 PMCID: PMC9179151 DOI: 10.1002/fsn3.2809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 12/10/2021] [Accepted: 12/13/2021] [Indexed: 11/07/2022] Open
Abstract
Recently, β-carotene has gained tremendous importance as a bioactive molecule due to the growing awareness of the harmful effects of synthetic products. β-carotene is a high-value natural pigment that has the highest demand in the global carotenoid market owing to its proven antioxidant properties relevant for several diseases. To date, Dunaliella salina is the most important producer of natural β-carotene and is the subject of important industrial efforts. However, the extraction of β-carotene remains challenging since all the proposed techniques present a risk of product contamination or loss of quality due to solvent residuals and low yields. The purpose of this study was to set up a green, ecological, and innovative process of extraction of the two major β-carotene isomers from the halophilic microalgae Dunaliella salina. Based on molecular modeling, docking, and drug design, we conceived and synthesized two chimeric peptides (PP2, PP3) targeting specifically the two major isomers: all-trans or 9-cis β-carotene. The experimental protocol used in this study demonstrated the ability and the efficacy of those two peptides to cross the cell membrane and bind with high affinity to β-carotene isomers and exclude them toward the extracellular medium while preserving the integrity of living cells. Interestingly, the tested peptides (PP2, PP3) exhibit significant β-carotene extraction yields 58% and 34%, respectively, from the total of the β-carotene in microalgae cells. In addition to its simplicity, this process is fast, independent of the source of the β-carotene, and selective. These results would allow us to set up a green, ecological, and very profitable process of extraction from microalgae containing high amounts of β-carotene. Our innovative approach is highly promising for the extraction of Dunaliella salina biomass on an industrial scale.
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Affiliation(s)
- Soumaya Kouidhi
- Laboratory (BVBGR)-LR11ES31 University Manouba ISBST Biotechnopole Sidi Thabet Ariana Tunisia
| | - Wissem Mnif
- Department of Chemistry Faculty of Sciences and Arts in Balgarn University of Bisha Bisha Saudi Arabia.,Laboratory of Biotechnology and Valorisation of Bio-GeoRessources Higher Institute of Biotechnology of Sidi Thabet BiotechPole of Sidi Thabet University of Manouba Ariana Tunisia
| | - Nada Alqarni
- Department of Chemistry Faculty of Sciences and Arts in Balgarn University of Bisha Bisha Saudi Arabia
| | - Soukaina Abdelwahed
- Laboratory (BVBGR)-LR11ES31 University Manouba ISBST Biotechnopole Sidi Thabet Ariana Tunisia
| | - Alaeddine Redissi
- Laboratory (BVBGR)-LR11ES31 University Manouba ISBST Biotechnopole Sidi Thabet Ariana Tunisia
| | - Nihel Ammous
- Laboratory of Molecular Biotechnology of Eukaryotes Center of Biotechnology of Sfax University of Sfax Sfax Tunisia
| | - Boulbaba Selmi
- Laboratory of Bioresources Integrative Biology and Valorization Higher Institute of Biotechnology of Monastir University of Monastir Monastir Tunisia
| | - Ali Gargouri
- Laboratory of Molecular Biotechnology of Eukaryotes Center of Biotechnology of Sfax University of Sfax Sfax Tunisia
| | - Sami Achour
- Laboratory of Bioresources Integrative Biology and Valorization Higher Institute of Biotechnology of Monastir University of Monastir Monastir Tunisia
| | - Ameur Cherif
- Laboratory (BVBGR)-LR11ES31 University Manouba ISBST Biotechnopole Sidi Thabet Ariana Tunisia
| | - Amor Mosbah
- Laboratory (BVBGR)-LR11ES31 University Manouba ISBST Biotechnopole Sidi Thabet Ariana Tunisia
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Zellama MS, Chahdoura H, Zairi A, Ziani BEC, Boujbiha MA, Snoussi M, Ismail S, Flamini G, Mosbah H, Selmi B, El-Bok S, Chaouachi M. Chemical characterization and nutritional quality investigations of healthy extra virgin olive oil flavored with chili pepper. Environ Sci Pollut Res Int 2022; 29:16392-16403. [PMID: 34651266 DOI: 10.1007/s11356-021-16645-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 09/16/2021] [Indexed: 06/13/2023]
Abstract
The production of extra virgin olive oil (EVOO) flavored with diverse spices, herbs, fruits, and vegetables or natural aromas is believed to provide advantageous properties considering either the high nutritional value or biological activity in addition to the flavoring and industrial aspects. The biological activities including antioxidant and antimicrobial properties of Tunisian EVOO obtained from "Chemlali" variety and mixed with chili pepper were investigated. Molecular analyses, including the detection of twelve olive-infecting viruses and Pseudomonas savastanoi pv savastanoi, were performed to ensure that the samples were obtained from healthy olive trees and EVOO quality was not affected. Quality parameters like free acidity, peroxide number, oxidative stability, and specific absorption at K232 nm and K270 nm were also investigated and no significant variation was revealed. The content of minor compounds such as chlorophylls, carotenoids, and total phenols showed minor changes. However, the profiles of the volatile compounds showed remarkable differences, which appeared to be the main factor for the observed variability in consumer acceptance. The results showed for the first time high quantities of polyphenols and ortho-diphenols. Four colorimetric methods were used for the determination of the antioxidant activity, namely DPPH, ABTS, FRAP, and β-carotene test. Compared to the control, a higher level of antioxidant activity was observed for the flavored EVOO. Furthermore, significant results were obtained in the antimicrobial tests. The quality parameters of the mixture showed no alteration compared to the control. Finally, all the measurements and the chemical characterization gave a scientific basis for food technology innovation of new food products.
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Affiliation(s)
- Mohamed Salem Zellama
- Laboratory of Bioresources: Integrative Biology and Exploiting, Higher Institute of Biotechnology of Monastir, University of Monastir, Avenue Taher Hadded BP 74, 5000, Monastir, Tunisia
| | - Hassiba Chahdoura
- Unité de Recherche UR17ES30 "Génomique, Biotechnologie et Stratégies Antivirales", Institut Supérieur de Biotechnologie, Université de Monastir, BP74, Avenue Tahar Hadded, 5000, Monastir, Tunisia
| | - Amira Zairi
- Laboratory of Bioresources: Integrative Biology and Exploiting, Higher Institute of Biotechnology of Monastir, University of Monastir, Avenue Taher Hadded BP 74, 5000, Monastir, Tunisia
| | | | - Mohamed Ali Boujbiha
- Laboratory of Bioresources: Integrative Biology and Exploiting, Higher Institute of Biotechnology of Monastir, University of Monastir, Avenue Taher Hadded BP 74, 5000, Monastir, Tunisia
| | - Mejdi Snoussi
- Department of Biology, University of Hail, P.O. 81451, Ha'il, Saudi Arabia
| | - Sara Ismail
- Laboratory of Bioresources: Integrative Biology and Exploiting, Higher Institute of Biotechnology of Monastir, University of Monastir, Avenue Taher Hadded BP 74, 5000, Monastir, Tunisia
| | - Guido Flamini
- Dipartimento di Farmacia, Università di Pisa, Via Bonanno 6, 56126, Pisa, Italy
- Centro Interdipartimentale di Ricerca "Nutraceutica e Alimentazione per la Salute", Università di Pisa, Via del Borghetto 80, 56124, Pisa, Italy
| | - Habib Mosbah
- Unité de Recherche UR17ES30 "Génomique, Biotechnologie et Stratégies Antivirales", Institut Supérieur de Biotechnologie, Université de Monastir, BP74, Avenue Tahar Hadded, 5000, Monastir, Tunisia
| | - Boulbaba Selmi
- Unité de Recherche UR17ES30 "Génomique, Biotechnologie et Stratégies Antivirales", Institut Supérieur de Biotechnologie, Université de Monastir, BP74, Avenue Tahar Hadded, 5000, Monastir, Tunisia
| | - Safia El-Bok
- Laboratoire de Biodiversité, Biotechnologies & Changements Climatiques (LR11ES09), Département de Biologie, Faculté des Sciences de Tunis, Université Tunis El-Manar, Campus Universitaire, 2092, Tunis, Tunisia
| | - Maher Chaouachi
- Unité de Recherche UR17ES30 "Génomique, Biotechnologie et Stratégies Antivirales", Institut Supérieur de Biotechnologie, Université de Monastir, BP74, Avenue Tahar Hadded, 5000, Monastir, Tunisia.
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Haddaji F, Papetti A, Noumi E, Colombo R, Deshpande S, Aouadi K, Adnan M, Kadri A, Selmi B, Snoussi M. Bioactivities and in silico study of Pergularia tomentosa L. phytochemicals as potent antimicrobial agents targeting type IIA topoisomerase, TyrRS, and Sap1 virulence proteins. Environ Sci Pollut Res Int 2021; 28:25349-25367. [PMID: 33454827 DOI: 10.1007/s11356-020-11946-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 12/02/2020] [Indexed: 06/12/2023]
Abstract
Pergularia tomentosa L. (P. tomentosa) has been largely used in Tunisian folk medicine as remedies against skin diseases, asthma, and bronchitis. The main objectives of this study were to identify phytochemical compounds that have antioxidant and antimicrobial properties from the stem, leaves, and fruit crude methanolic extracts of P. tomentosa, and to search for tyrosyl-tRNA synthetase (TyrRS), topoisomerase type IIA, and Candidapepsin-1 (SAP1) enzyme inhibitors through molecular docking study. Phytochemical quantification revealed that fruit and leaves extracts displayed the highest total flavonoids (582 mg QE/g Ex; 219 mg QE/g Ex) and tannins content (375 mg TAE/g Ex; 216 mg TAE/g Ex), also exhibiting significant scavenging activity to decrease free radicals for ABTS, DPPH, β-carotene, and FRAP assay with IC50 values (> 1 mg/mL). Additionally, promising antimicrobial activities towards different organs have been observed against several bacteria and Candida strains. From the liquid chromatography-mass spectrometry (LC-MS) analysis, five polyphenolic compounds, namely digitoxigenin, digitonin glycoside and calactina in the leaves, kaempferol in the fruit, and calotropagenin in the stems, were identified. They were also analyzed for their drug likeliness, based on computational methods. Molecular docking study affirmed that the binding affinity of calactin and actodigin to the active site of TyrRS, topoisomerase type IIA, and SAP1 target virulence proteins was the highest among the examined dominant compounds. Therefore, this study indicated that P. tomentosa methanolic extracts displayed great potential to become a potent antimicrobial agent and might be a promising source for therapeutic and nutritional functions. These phytocompounds could be further promoted as a candidate for drug discovery and development.
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Affiliation(s)
- Fatma Haddaji
- Laboratory of Genetics, Biodiversity and Valorization of Bio-resources (LR11ES41), University of Monastir, Higher Institute of Biotechnology of Monastir, Avenue Tahar Haddad, BP74, 5000, Monastir, Tunisia
| | - Adele Papetti
- Nutraceutical & Food Chemical-Toxicological Analysis Laboratory, Department of Drug Sciences, University of Pavia, Viale Taramelli 12, 27100, Pavia, Italy
| | - Emira Noumi
- Department of Biology, College of Science, University of Ha'il, P.O. 2440, Hail, Saudi Arabia
- Laboratory of Bioressources: Integrative Biology and Valorization, (LR14-ES06), University of Monastir, Higher Institute of Biotechnology of Monastir, Avenue Tahar Haddad, BP 74, 5000, Monastir, Tunisia
| | - Raffaella Colombo
- Nutraceutical & Food Chemical-Toxicological Analysis Laboratory, Department of Drug Sciences, University of Pavia, Viale Taramelli 12, 27100, Pavia, Italy
| | - Sumukh Deshpande
- Central Biotechnology Services, College of Biomedical and Life Sciences, Cardiff University, Cardiff, Wales, CF14 4XN, UK
| | - Kaïss Aouadi
- Faculty of Science and Arts in Baljurashi, Albaha University, P.O. Box 1988, Albaha, Saudi Arabia
- Faculty of Science of Monastir, Laboratory of Hetrocyclic Chemistry, Natural Products and Reactivity, Avenue of the Environment, University of Monastir, 5019, Monastir, Tunisia
| | - Mohd Adnan
- Department of Biology, College of Science, University of Ha'il, P.O. 2440, Hail, Saudi Arabia
| | - Adel Kadri
- Faculty of Science of Sfax, Department of Chemistry, University of Sfax, B.P. 1171, 3000, Sfax, Tunisia
- Department of Chemistry, College of Science, Qassim University, Buraidah, 51452, Saudi Arabia
| | - Boulbaba Selmi
- Laboratory of Bioressources: Integrative Biology and Valorization, (LR14-ES06), University of Monastir, Higher Institute of Biotechnology of Monastir, Avenue Tahar Haddad, BP 74, 5000, Monastir, Tunisia
| | - Mejdi Snoussi
- Department of Biology, College of Science, University of Ha'il, P.O. 2440, Hail, Saudi Arabia.
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Mosbah H, Sassi AB, Chahdoura H, Snoussi M, Flamini G, Achour L, Selmi B. Antioxidant, antimicrobial and phytotoxic activities of Rhaponticum acaule DC. essential oil. BRAZ J PHARM SCI 2020. [DOI: 10.1590/s2175-97902019000318483] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Habib Mosbah
- Higher Institute of Biotechnology of Monastir, Tunisia
| | | | | | - Mejdi Snoussi
- Higher Institute of Biotechnology of Monastir, Tunisia
| | - Guido Flamini
- Università di Pisa, Italy; Università di Pisa, Italy
| | - Lotfi Achour
- Higher Institute of Biotechnology of Monastir, Tunisia
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Hamden K, Boujibiha MA, Ben Abdeljelil N, Njima M, Selmi B, Achour L. Phytoestrogens inhibit key-enzymes linked to obesity, type 2 diabetes and liver-kidney toxicity in high fructose-fat diet in mice. Arch Physiol Biochem 2019; 125:423-429. [PMID: 29898610 DOI: 10.1080/13813455.2018.1479427] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
Objective: To evaluate the effect of the administration of phytoestrogens on obesity, type 2 diabetes, and liver-kidney toxicity. Methods: Phytoestrogens (phyto(E2)) were administrated to high fructose-fat diet (HFFD). Results: This study showed that administration of phyto(E2) to HFFD-mice inhibited lipase activity by 34%, decreased body weight by 20% and modulated lipid profile, showed a decrease in total-cholesterol (TC) and LDL-cholesterol (LDL-C) rates in the plasma by 59% and 42%, respectively, and increased the HDL-cholesterol (HDL-C) level by 31%. In addition, the administration of phytoestrogens to HFFD-mice exerts an inhibitory effect on α-amylase activity and decreased glucose level by 28% and increase in liver glycogen level by 33%; and ameliorate oral glucose tolerance test. Conclusions: This study demonstrate that phyto(E2) has both a promising potential with regards to the inhibition of intestinal lipase and α-amylase activities, and a valuable hypoglycemic and hypolipidemic function.
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Affiliation(s)
- Khaled Hamden
- Laboratory of Bioresources: Integrative Biology and Valorisation, Higher Institute of Biotechnology of Monastir, University of Monastir , Monastir , Tunisia
| | - Mohamed Ali Boujibiha
- Laboratory of Bioresources: Integrative Biology and Valorisation, Higher Institute of Biotechnology of Monastir, University of Monastir , Monastir , Tunisia
| | - Nouha Ben Abdeljelil
- Laboratory of Histology-Pathology, CHU Fattoma Bourguiba, University of Monastir , Monastir Tunisia
| | - Manel Njima
- Laboratory of Histology-Pathology, CHU Fattoma Bourguiba, University of Monastir , Monastir Tunisia
| | - Boulbaba Selmi
- Laboratory of Bioresources: Integrative Biology and Valorisation, Higher Institute of Biotechnology of Monastir, University of Monastir , Monastir , Tunisia
| | - Lotfi Achour
- Laboratory of Bioresources: Integrative Biology and Valorisation, Higher Institute of Biotechnology of Monastir, University of Monastir , Monastir , Tunisia
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Limam S, Missaoui N, Mestiri S, Yacoubi M, Krifa H, Selmi B, Mokni M. Epstein-Barr virus infection in gliomas. Curr Res Transl Med 2019; 67:129-133. [DOI: 10.1016/j.retram.2019.06.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 06/07/2019] [Accepted: 06/30/2019] [Indexed: 12/23/2022]
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Mosbah H, Chahdoura H, Adouni K, Kamoun J, Boujbiha MA, Gonzalez-Paramas AM, Santos-Buelga C, Ciudad-Mulero M, Morales P, Fernández-Ruiz V, Achour L, Selmi B. Nutritional properties, identification of phenolic compounds, and enzyme inhibitory activities of Feijoa sellowiana leaves. J Food Biochem 2019; 43:e13012. [PMID: 31385325 DOI: 10.1111/jfbc.13012] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 07/22/2019] [Accepted: 07/23/2019] [Indexed: 12/01/2022]
Abstract
The nutritional values, the identification of individual phenolic compounds as well as the functional properties (in vitro acetylcholinesterase (AChE) and pancreatic lipase inhibition) of Tunisian Feijoa sellowiana (O.Berg) leaves were determined by high-performance liquid chromatography coupled with diode array and mass spectrometry detector. Feijoa Sellowiana leaves Extract (FSLE) were evaluated in the present work. Macronutrient components (proteins, carbohydrates, dietary fiber, lipids, and ashes) of FSLE as well as their fatty acids and mineral content were determined. The individual phenolic composition was characterized by the presence of flavonols (mostly quercetin glycosides), flavan-3-ols (procyanidins and catechins), and phenolic acid derivatives. To understand the possible inhibition mechanism exerted by the extract components, enzyme kinetic studies using derived Lineweaver-Burk (LB) plots and Michaelis-Menten were performed. The obtained results evidenced that FSLE exhibited important AChE inhibitory effect, behaving as a noncompetitive inhibitor. Furthermore, the leaves' extract inhibited irreversibly the pancreatic lipase, with maximum inhibition (70%) achieved at 1 mg/ml. PRACTICAL APPLICATIONS: In many countries of the world, Feijoa Sellowiana leaves are used as an alternative to tea drinks and as a folkloric medicine. Moreover, it is well known that the phytochemical compounds are a practical alternative for the prevention of many chronic diseases such as Alzheimer's and obesity. For this reason, the present study aimed to evaluate the nutritional, individual phenolic compounds, and functional properties of Feijoa Sellowiana leaves to valorize them as a food and pharmaceutical bioactive human source.
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Affiliation(s)
- Habib Mosbah
- Laboratoire de Recherche Bioressources: Biologie Intégrative & Valorisation, Institut Supérieur de Biotechnologie de Monastir, Université de Monastir, Monastir, Tunisia
| | - Hassiba Chahdoura
- Laboratoire de Recherche Bioressources: Biologie Intégrative & Valorisation, Institut Supérieur de Biotechnologie de Monastir, Université de Monastir, Monastir, Tunisia
| | - Khaoula Adouni
- Laboratoire de Recherche Bioressources: Biologie Intégrative & Valorisation, Institut Supérieur de Biotechnologie de Monastir, Université de Monastir, Monastir, Tunisia
| | - Jannet Kamoun
- Laboratoire de Biochimie et de Génie enzymatique des Lipases, ENIS, Sfax, Tunisia
| | - Mohamed Ali Boujbiha
- Laboratoire de Recherche Bioressources: Biologie Intégrative & Valorisation, Institut Supérieur de Biotechnologie de Monastir, Université de Monastir, Monastir, Tunisia
| | - Ana M Gonzalez-Paramas
- Grupo de Investigación en Polifenoles (GIP-USAL), Facultad de Farmacia, Universidad de Salamanca, Salamanca, Spain
| | - Celestino Santos-Buelga
- Grupo de Investigación en Polifenoles (GIP-USAL), Facultad de Farmacia, Universidad de Salamanca, Salamanca, Spain
| | - María Ciudad-Mulero
- Departament of Nutrition and Food Science, Faculty of Pharmacy, Complutense University of Madrid, Madrid, Spain
| | - Patricia Morales
- Departament of Nutrition and Food Science, Faculty of Pharmacy, Complutense University of Madrid, Madrid, Spain
| | - Virginia Fernández-Ruiz
- Departament of Nutrition and Food Science, Faculty of Pharmacy, Complutense University of Madrid, Madrid, Spain
| | - Lotfi Achour
- Laboratoire de Recherche Bioressources: Biologie Intégrative & Valorisation, Institut Supérieur de Biotechnologie de Monastir, Université de Monastir, Monastir, Tunisia
| | - Boulbaba Selmi
- Laboratoire de Recherche Bioressources: Biologie Intégrative & Valorisation, Institut Supérieur de Biotechnologie de Monastir, Université de Monastir, Monastir, Tunisia
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Mosbah H, Chahdoura H, Kammoun J, Hlila MB, Louati H, Hammami S, Flamini G, Achour L, Selmi B. Rhaponticum acaule (L) DC essential oil: chemical composition, in vitro antioxidant and enzyme inhibition properties. BMC Complement Altern Med 2018; 18:79. [PMID: 29506517 PMCID: PMC5838999 DOI: 10.1186/s12906-018-2145-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 02/26/2018] [Indexed: 01/03/2023]
Abstract
BACKGROUND α-glucosidase is a therapeutic target for diabetes mellitus (DM) and α-glucosidase inhibitors play a vital role in the treatments for the disease. Furthermore, xanthine oxidase (XO) is a key enzyme that catalyzes hypoxanthine and xanthine to uric acid which at high levels can lead to hyperuricemia which is an important cause of gout. Pancreatic lipase (PL) secreted into the duodenum plays a key role in the digestion and absorption of fats. For its importance in lipid digestion, PL represents an attractive target for obesity prevention. METHODS The flowers essential oil of Rhaponticum acaule (L) DC (R. acaule) was characterized using gas chromatography-mass spectrometry (GC-MS). The antioxidant activities of R. acaule essential oil (RaEO) were also determined using 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), reducing power, phosphomolybdenum, and DNA nicking assays. The inhibitory power of RaEO against α-glucosidase, xanthine oxidase and pancreatic lipase was evaluated. Enzyme kinetic studies using Michaelis-Menten and the derived Lineweaver-Burk (LB) plots were performed to understand the possible mechanism of inhibition exercised by the components of this essential oil. RESULTS The result revealed the presence of 26 compounds (97.4%). The main constituents include germacrene D (49.2%), methyl eugenol (8.3%), (E)-β-ionone (6.2%), β-caryophyllene (5.7%), (E,E)-α-farnesene (4.2%), bicyclogermacrene (4.1%) and (Z)-α-bisabolene (3.7%). The kinetic inhibition study showed that the essential oil demonstrated a strong α-glucosidase inhibiton and it was a mixed inhibitor. On the other hand, our results evidenced that this oil exhibited important xanthine oxidase inhibitory effect, behaving as a non-competitive inhibitor. The essential oil inhibited the turkey pancreatic lipase, with maximum inhibition of 80% achieved at 2 mg/mL. Furthermore, the inhibition of turkey pancreatic lipase by RaEO was an irreversible one. CONCLUSION The results revealed that the RaEO is a new promising potential source of antioxidant compounds, endowed with good practical applications for human health.
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Affiliation(s)
- Habib Mosbah
- Laboratory of Bioresources: Integrative Biology and Valorization, Higher Institute of Biotechnology of Monastir, Avenue Taher Hadded BP 74, 5000 Monastir, Tunisia
| | - Hassiba Chahdoura
- Laboratory of Bioresources: Integrative Biology and Valorization, Higher Institute of Biotechnology of Monastir, Avenue Taher Hadded BP 74, 5000 Monastir, Tunisia
| | - Jannet Kammoun
- Laboratory of Biochemistry and Enzymatic Engineering of Lipases, ENIS, 3038 Sfax, Tunisia
| | - Malek Besbes Hlila
- Laboratory of Transmissible Diseases and Biological Active Substances, Faculty of Pharmacy, Avicenne Avenue, 5000 Monastir, Tunisia
| | - Hanen Louati
- Laboratory of Biochemistry and Enzymatic Engineering of Lipases, ENIS, 3038 Sfax, Tunisia
| | - Saoussen Hammami
- Research Unit Applied Chemistry and Environment (UR13ES63), Faculty of Sciences of Monastir, Environment Avenue, 5019 Monastir, Tunisia
| | - Guido Flamini
- Dipartimento di Farmacia, Via Bonanno 6, 56126 Pisa, Italy
- Centro Interdipartimentale di Ricerca “Nutraceutica e Alimentazione per la Salute”, Università di Pisa, Pisa, Italy
| | - Lotfi Achour
- Laboratory of Bioresources: Integrative Biology and Valorization, Higher Institute of Biotechnology of Monastir, Avenue Taher Hadded BP 74, 5000 Monastir, Tunisia
| | - Boulbaba Selmi
- Laboratory of Bioresources: Integrative Biology and Valorization, Higher Institute of Biotechnology of Monastir, Avenue Taher Hadded BP 74, 5000 Monastir, Tunisia
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Hlila MB, Lamar A, Hichri AO, Jannet HB, Mastouri M, Aouni M, Selmi B. Larvicidal efficacy of Scabiosa arenaria Forssk. (Dipsacaceae) organs extracts against Culex pipiens L. APJTD 2017. [DOI: 10.12980/apjtd.7.2017d7-175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Hlila MB, Majouli K, Jannet HB, Mastouri M, Aouni M, Selmi B. Antioxidant and anti α-glucosidase of luteolin and luteolin 7-O-glucoside isolated from Scabiosa arenaria Forssk. ACTA ACUST UNITED AC 2017. [DOI: 10.12980/jclm.5.2017j7-66] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Besbes Hlila M, Mosbah H, Majouli K, Ben Nejma A, Ben Jannet H, Mastouri M, Aouni M, Selmi B. Antimicrobial Activity ofScabiosa arenariaForssk. Extracts and Pure Compounds Using Bioguided Fractionation. Chem Biodivers 2016; 13:1262-1272. [DOI: 10.1002/cbdv.201600028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 06/03/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Malek Besbes Hlila
- Laboratory of Transmissible Diseases and Biological Active Substances; Faculty of Pharmacy; University of Monastir; Avenue Avicenne 5000 Monastir Tunisia
| | - Habib Mosbah
- Laboratory of Bioresources, Integrative Biology and Exploiting; Higher Institute of Biotechnology of Monastir; Taher Hadded Avenue 5000 Monastir Tunisia
| | - Kaouther Majouli
- Laboratory of Biochemistry, Cell Signaling and Disease; Research Unit; UR 12ES08; Faculty of Medicine of Monastir; Avenue Avicenne, 5019 Monastir Tunisia
| | - Aymen Ben Nejma
- Laboratory of Heterocyclic Chemistry, Natural Products and Reactivity; Team: Medicinal Chemistry and Natural Products; Faculty of Sciences of Monastir; University of Monastir; Avenue de l’Environnement 5019 Monastir Tunisia
| | - Hichem Ben Jannet
- Laboratory of Heterocyclic Chemistry, Natural Products and Reactivity; Team: Medicinal Chemistry and Natural Products; Faculty of Sciences of Monastir; University of Monastir; Avenue de l’Environnement 5019 Monastir Tunisia
| | - Maha Mastouri
- Laboratory of Transmissible Diseases and Biological Active Substances; Faculty of Pharmacy; University of Monastir; Avenue Avicenne 5000 Monastir Tunisia
| | - Mahjoub Aouni
- Laboratory of Transmissible Diseases and Biological Active Substances; Faculty of Pharmacy; University of Monastir; Avenue Avicenne 5000 Monastir Tunisia
| | - Boulbaba Selmi
- Laboratory of Bioresources, Integrative Biology and Exploiting; Higher Institute of Biotechnology of Monastir; Taher Hadded Avenue 5000 Monastir Tunisia
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Omri Hichri A, Mosbah H, Majouli K, Besbes Hlila M, Ben Jannet H, Flamini G, Aouni M, Selmi B. Chemical composition and biological activities of Eruca vesicaria subsp. longirostris essential oils. Pharm Biol 2016; 54:2236-2243. [PMID: 26983675 DOI: 10.3109/13880209.2016.1151445] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Context To date, there are no reports to validate the Tunisian traditional and folklore claims of Eruca vesicaria (L) Cav. subsp. longirostris (Brassicaceae) for the treatment of disease. Objective Investigation of the chemical composition antimicrobial and antioxidant activity of essential oils from Eruca longirostris leaves, stems, roots and fruits. Materials and methods The essential oils of E. longirostris from leaves, stems, roots and fruits were obtained after 4 h of hydrodistillation. Chemical compositions were determined using a combination of GC/FID and GC/MS. The in vitro antimicrobial activity of the volatile constituents of E. longirostris was performed in sterile 96-well microplates against three Gram-positive, four Gram-negative bacteria and one strain as yeast. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration values were reported. Furthermore, the antioxidant activity was evaluated by DPPH and ABTS assays. Results The main compound for fruits, stems and roots was the erucin (96.6%, 85.3% and 83.7%, respectively), while β-elemene (35.7%), hexahydrofarnesylacetone (23.9%), (E)-β-damascone (15.4%), erucin (10.6%) and α-longipinene (9.6%) constituted the major compounds in the essential oil of the leaves. The experimental results showed that in all tests, essential oil of fruits showed the better antioxidant activity than the others. On the other hand, the oils of stems, fruits and roots showed significant antimicrobial activity with MIC values ranging from 0.125 to 0.31 mg/mL against Candida species, Gram-positive and Gram-negative bacteria, mainly Salmonella enterica. Conclusions The present results indicate that essential oils of E. longirostris can be used as a source of erucin.
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Affiliation(s)
- Amel Omri Hichri
- a Laboratoire Des Maladies Transmissibles Et Des Substances Biologiquement Actives, Faculté De Pharmacie , Monastir , Tunisia
| | - Habib Mosbah
- b Laboratoire De Bioressources: Biologie Integrative Et Valorisation (BIOLIVAL) , Institut Supérieur De Biotechnologie De Monastir, Université De Monastir , Monastir , Tunisia
| | - Kaouther Majouli
- c Laboratoire De Biochimie, Mécanismes Moléculaires Et Maladie, Faculté De Médecine De Monastir , Université De Monastir , Monastir , Tunisia
| | - Malek Besbes Hlila
- a Laboratoire Des Maladies Transmissibles Et Des Substances Biologiquement Actives, Faculté De Pharmacie , Monastir , Tunisia
| | - Hichem Ben Jannet
- d Laboratoire De Chimie Hétérocyclique, Produits Naturels Et Réactivité, Equipe: Chimie Médicinale Et Produits Naturels, Faculté Des Sciences De Monastir , Université De Monastir , Monastir , Tunisia
| | - Guido Flamini
- e Dipartimento Di Farmacia , via Bonanno , Pisa , Italy
| | - Mahjoub Aouni
- a Laboratoire Des Maladies Transmissibles Et Des Substances Biologiquement Actives, Faculté De Pharmacie , Monastir , Tunisia
| | - Boulbaba Selmi
- b Laboratoire De Bioressources: Biologie Integrative Et Valorisation (BIOLIVAL) , Institut Supérieur De Biotechnologie De Monastir, Université De Monastir , Monastir , Tunisia
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Hlila MB, Mosbah H, Zanina N, Ben Nejma A, Ben Jannet H, Aouni M, Selmi B. Characterisation of phenolic antioxidants in Scabiosa arenaria flowers by LC-ESI-MS/MS and NMR. ACTA ACUST UNITED AC 2016; 68:932-40. [PMID: 27230582 DOI: 10.1111/jphp.12561] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 03/29/2016] [Indexed: 11/30/2022]
Abstract
OBJECTIVES This work describes the bioguided fractionation of the flower's ethyl acetate fraction of Scabiosa arenaria Forssk. (Dipsacaceae). METHODS The identification of the pure compound isolated has been studied by mono-dimensional NMR experiments. The mixture of phenolic compounds was analysed by LC-ESI-MS/MS. The antioxidant activity has been evaluated by the 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay. KEY FINDINGS The bioguided fractionation of the flower's ethyl acetate fraction of Scabiosa arenaria led to the isolation of a pure compound: luteolin. The mixture of three phenolic compounds was identified as: 1, 4-O-dicaffeoylquinic acid, apigenin 7-O-glucoside and luteolin-7-O-glucoside. Two of which are reported here for the first time in Scabiosa genus. Luteolin had the highest antioxidant activity with an IC50 value of 0.02 ± 0.007 mg/ml, followed by the three phenolic compounds with an IC50 value of 0.025 ± 0.008 mg/ml. CONCLUSIONS The results of the present work indicate that S. arenaria flower's ethyl acetate extract could be used as natural antioxidant agents in food preservation and human health.
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Affiliation(s)
- Malek Besbes Hlila
- Laboratory of Transmissible Diseases and Biological Active Substances, Faculty of Pharmacy, University of Monastir, Monastir, Tunisia
| | - Habib Mosbah
- Laboratory of Bioresources: Integrative Biology and exploiting, Higher Institute of Biotechnology of Monastir, Monastir, Tunisia
| | - Nahla Zanina
- Laboratory of Biophysics, Faculty of Medicine, Monastir University, Monastir, Tunisia
| | - Aymen Ben Nejma
- Laboratory of Heterocyclic Chemistry, Natural Products and Reactivity, Team: Medicinal Chemistry and Natural Products, Faculty of Sciences of Monastir, University of Monastir, Monastir, Tunisia
| | - Hichem Ben Jannet
- Laboratory of Heterocyclic Chemistry, Natural Products and Reactivity, Team: Medicinal Chemistry and Natural Products, Faculty of Sciences of Monastir, University of Monastir, Monastir, Tunisia
| | - Mahjoub Aouni
- Laboratory of Transmissible Diseases and Biological Active Substances, Faculty of Pharmacy, University of Monastir, Monastir, Tunisia
| | - Boulbaba Selmi
- Laboratory of Bioresources: Integrative Biology and exploiting, Higher Institute of Biotechnology of Monastir, Monastir, Tunisia
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Hlila MB, Mosbah H, Majouli K, Msaada K, Jannet HB, Aouni M, Selmi B. α-Glucosidase inhibition by Tunisian Scabiosa arenaria Forssk. extracts. Int J Biol Macromol 2015; 77:383-9. [DOI: 10.1016/j.ijbiomac.2015.03.035] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2014] [Revised: 03/19/2015] [Accepted: 03/20/2015] [Indexed: 11/28/2022]
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Selmi B, Engelmann G, Flechtenmacher C, Teufel U, Sakka SE, Schenk JP. Real-time tissue Elastografie (RTE) für nicht-invasive Bestimmung der Leberfibrose bei pädiatrischen Lebererkrankungen im Vergleich zur Leberbiopsie. ROFO-FORTSCHR RONTG 2014. [DOI: 10.1055/s-0034-1373589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Bergaoui I, Zaïri A, Gharsallah H, Aouni M, Hammami A, Hani K, Selmi B. The in vitro evaluation of anti-chlamydial and cytotoxic properties of dermaseptin S4 and derivatives: peptides from amphibian skin. Med Chem Res 2013. [DOI: 10.1007/s00044-013-0601-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Besbes Hlila M, Omri A, Ben Jannet H, Lamari A, Aouni M, Selmi B. Phenolic composition, antioxidant and anti-acetylcholinesterase activities of the Tunisian Scabiosa arenaria. Pharm Biol 2013; 51:525-532. [PMID: 23368937 DOI: 10.3109/13880209.2012.746713] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
CONTEXT There is a need for the discovery of novel natural antioxidants and acetylcholinesterase inhibitors (AChEIs) that are safe and effective at a global level. This is the first study on antioxidant and anti-acethylcholinesterase activity of Scabiosa arenaria Forssk (Dipsacaceae). OBJECTIVE The antioxidant potential and anti-acetylcholinesterase (AChE) activity of S. arenaria were investigated. MATERIAL AND METHODS The crude, ethyl acetate (EtOAc), butanol (n-BuOH) and water extracts prepared from flowers, fruits and stems and leaves of S. arenaria were tested to determine their total polyphenol content (TPC), total flavonoid content (TFC), total condensed tannin content (CTC) and their antioxidant activity by using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), reducing power and β-carotene bleaching inhibition activity. Anti-AChE activity was also determined. RESULTS EtOAc and n-BuOH fractions of fruits had both the highest (TPC) (269.09 mg gallic acid equivalents/g dry weight). The crude extract of stems and leaves had the highest TFC (10.9 mg quercetin equivalent/g dry weight). The n-BuOH fraction of stems and leaves had the highest CTC (489.75 mg catechin equivalents/g dry weight). The EtOAc fraction of flowers exhibit a higher activity in each antioxidant system with a special attention for DPPH assay (IC50 = 0.017 mg/mL) and reducing power (EC50 = 0.02 mg/mL). The EtOAc and n-BuOH fractions of stems and leaves showed strong inhibition of AChE (IC50 = 0.016 and 0.029 mg/mL, respectively). DISCUSSION AND CONCLUSIONS These results suggest the potential of S. arenaria as a possible source of novel compounds and as an alternative antioxidant and AChEIs.
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Affiliation(s)
- Malek Besbes Hlila
- Laboratoire des maladies transmissibles et des substances biologiquement actives, Faculté de Pharmacie, Monastir, Tunisie
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Bergaoui I, Zairi A, Tangy F, Aouni M, Selmi B, Hani K. In vitro antiviral activity of dermaseptin S(4) and derivatives from amphibian skin against herpes simplex virus type 2. J Med Virol 2012; 85:272-81. [PMID: 23161023 DOI: 10.1002/jmv.23450] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/28/2012] [Indexed: 01/09/2023]
Abstract
Herpes simplex virus (HSV) infections have become a public health problem worldwide. The emergence of acyclovir-resistant viral strains and the failure of vaccination to prevent herpetic infections have prompted the search for new antiviral drugs. Accordingly, the present study was undertaken to synthesize chemically and evaluate Dermaseptin S(4) (S(4)), an anti-microbial peptide derived from amphibian skin, and its derivatives in terms of anti-herpetic activity. The effects of biochemical modifications on their antimicrobial potential were also investigated. The peptides were incubated together with HSV-2 on target cells under various conditions, and the antiviral effects were examined via a cell metabolic labeling method. The findings revealed that DS(4) derivatives elicited concentration-dependent antiviral activity at micromole concentrations. The biochemical modifications of S(4) allowed for the reduction of peptide cytotoxicity without altering antiviral activity. Dermaseptins were added at different times during the viral cycle to investigate the mode of antiviral action. At the highest non-cytotoxic concentrations, most of the tested derivatives were noted to exhibit high antiviral activity particularly when pre-incubated with free herpes viruses prior to infection. Among these peptides, K(4)K(20)S(4) exhibited the highest antiviral activity against HSV-2 sensitive and resistant strains. Interestingly, the antiviral activity of K(4)K(20)S(4) was effective on both acyclovir-resistant and -sensitive viruses. The findings indicate that K(4)K(20)S(4) can be considered a promising candidate for future application as a therapeutic virucidal agent for the treatment of herpes viruses.
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Besbes M, Omri A, Cheraif I, Daami M, Jannet HB, Mastouri M, Aouni M, Selmi B. Chemical composition and antimicrobial activity of essential oils from Scabiosa arenaria Forssk: growing wild in Tunisia. Chem Biodivers 2012; 9:829-39. [PMID: 22492499 DOI: 10.1002/cbdv.201100191] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The essential oils isolated from three organs, i.e., fruits, stems and leaves, and flowers, of the endemic North African plant Scabiosa arenaria Forssk. were screened for their chemical composition, as well as their possible antibacterial, anticandidal, and antifungal properties. According to the GC-FID and GC/MS analyses, 61 (99.26% of the total oil composition), 79 (98.43%), and 51 compounds (99.9%) were identified in the three oils, respectively. While α-thujone (34.39%), camphor (17.48%), and β-thujone (15.29%) constituted the major compounds of the fruit oil, chrysanthenone (23.43%), together with camphor (12.98%) and α-thujone (10.7%), were the main constituents of the stem and leaf oil. In the case of the flower oil, also chrysanthenone (38.52%), camphor (11.75%), and α-thujone (9.5%) were identified as the major compounds. Furthermore, the isolated oils were tested against 16 Gram-positive and Gram-negative bacteria, four Candida species, and nine phytopathogenic fungal strains. It was found that the oils exhibited interesting antibacterial and anticandidal activities, comparable to those of thymol, which was used as positive control, but no activity against the phytopathogenic fungal strains was observed.
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Affiliation(s)
- Malek Besbes
- Laboratoire des Maladies Transmissibles et des Substances Biologiquement Actives, Monastir, Tunisie
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Selmi B, Schenk JP, Engelmann G, Teufel U, Grulich-Henn J, El Sakka S. Real-time tissue Elastographie (RTE): Normkollektiv und klinische Anwendung im Kindesalter - erste Ergebnisse. ROFO-FORTSCHR RONTG 2012. [DOI: 10.1055/s-0032-1311026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Aref HL, Mosbah H, Louati H, Said K, Selmi B. Partial characterization of a novel amylase activity isolated from Tunisian Ficus carica latex. Pharm Biol 2011; 49:1158-1166. [PMID: 22014263 DOI: 10.3109/13880209.2011.575791] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
CONTEXT A large number of plants still need to be investigated through screening of amylases suitable for industry. In the present study, and for the first time, we describe the amylolytic activity of Saint Pedro Ficus carica L. (Moraceae) crude latex of Kahli and Bidhi varieties. OBJECTIVE Effects of temperature, pH, metal ions, and inhibitors and compatibility with some commercial detergents were investigated for amylase activity. MATERIALS AND METHODS Amylase activity was screened in crude latex using the DNS method and potato starch as a substrate. Analyses of amylolytic reaction products by thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC) were performed. RESULTS Bidhi and Kahli amylases were active in optimal pH of 6.5 and 7 at 45°C, respectively, displaying a half life of 85 and 60 min, respectively, at 80°C, and they were very stable in a wide range of pH (4-12). Bidhi amylase activity increased to 260% by addition of 10(-3) mM Fe(2+) or 10(-2) mM Cu(2+), and was strongly inhibited by Mg(2+) and EDTA. In the presence of Ca(2+) and Mg(2+), Kahli amylase activity was dramatically enhanced by 220 and 260%, respectively. The compatibility of both amylases with certain commercial detergents was also shown to be good as enzymes retained up to 98% of their activities after 30 min of incubation at 80°C. DISCUSSION AND CONCLUSION Analysis of amylolytic reaction products by TLC and HPLC suggested that Kahli amylase was an amyloglucosidase and Bidhi amylase was β-fructose, α(1-4) glucose. Bidhi amylase is a good choice for application in starch, food, detergents and medical industries.
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Affiliation(s)
- Houda Lazreg Aref
- Laboratoire de Génétique, Biodiversité et Valorisation des Bio ressources (UR 03ES09), Institut Supérieur de Biotechnologie, Monastir, Tunisia.
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Miladi S, Abid N, Debarnôt C, Damak M, Canard B, Aouni M, Selmi B. In vitro antiviral activities of extracts derived from Daucus maritimus seeds. Nat Prod Res 2011; 26:1027-32. [PMID: 21895456 DOI: 10.1080/14786419.2010.550263] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The antiviral activities of extracts from Daucus maritimus seeds were investigated against the reverse transcriptase of human immunodeficiency virus (HIV) type 1 and a panel of RNA-dependent RNA polymerases of dengue virus, West Nile virus (WNV) and hepatitis C virus (HCV). The extracts showed moderate to potent inhibition rates against the four viral polymerases. The ethyl acetate extract exhibited a potent inhibitory effect against WNV's RdRp, with an IC₅₀ value of 8 µg mL⁻¹. The F₂ fraction exhibited potent inhibitory activity against WNV and HCV's RdRps, with IC₅₀ values 1 and 5 µg mL⁻¹, respectively. The P₂ fraction also showed potent inhibitory effects on WNV and HCV's RdRps, with IC₅₀ values 2.7 and 4 µg mL⁻¹, respectively. The results suggest that these extracts are candidates for the development of new anti-WNV RpDp and anti-HCV RpDp agents.
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Affiliation(s)
- S Miladi
- Laboratoire de Chimie des Substances Naturelles, Faculté des Sciences de Sfax- BP 1171, 3000 Sfax, Tunisia
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Selmi B, Engelmann G, Teufel U, El Sakka S, Grulich-Henn J, Schenk JP. Real-time tissue Elastografie (RTE): Normkollektiv und klinische Anwendung im Kindesalter – erste Ergebnisse. ROFO-FORTSCHR RONTG 2011. [DOI: 10.1055/s-0031-1286233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Schenk JP, Teufel U, Gebhardt C, Selmi B, El Sakka S, Wühl E, Engelmann G. Transiente Elastografie (TE) – eine ergänzende Diagnostik zur Lebersonografie: Normwerte und klinische Anwendung im Kindesalter. ROFO-FORTSCHR RONTG 2011. [DOI: 10.1055/s-0031-1286226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Feng JY, Myrick FT, Margot NA, Mulamba GB, Rimsky L, Borroto-Esoda K, Selmi B, Canard B. Virologic and enzymatic studies revealing the mechanism of K65R- and Q151M-associated HIV-1 drug resistance towards emtricitabine and lamivudine. Nucleosides Nucleotides Nucleic Acids 2006; 25:89-107. [PMID: 16440988 DOI: 10.1080/15257770500379157] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Emtricitabine (FTC) and lamivudine (3TC) are deoxycytidine analogues with potent and selective inhibition of human immunodeficiency virus (HIV) and hepatitis B virus (HBV) replication. The K65R mutation in the HIV reverse transcriptase (RT) confers reduced susceptibility to 3TC, ddC, ddI, abacavir, and tenofovir in vitro. The Q151M mutation confers reduced susceptibility to many of the approved anti-HIV nucleoside analogues with the exception of 3TC and tenofovir. The double mutation K65R/Q151M has been shown to be more resistant to many NRTIs than either of the single mutations alone. In this study, we measured the antiviral activity of FTC and 3TC against HIV-1 containing K65R, Q151M, and K65R/Q151M mutations. We also studied the steady-state kinetic properties for the inhibition of dCTP incorporation by FTC 5'-triphosphate (TP) and 3TC-TP In addition, we measured the incorporation of dCTP, FTC-TP, and 3TC-TP into a random sequence DNA/DNA primer/template by the HIV-1 RTs using pre-steady-state kinetic analysis. Finally, we studied the incorporation of these deoxycytidine analogues into a HIV-1 genomic DNA/DNA primer/template by K65R HIV-1 RT to address certain concerns associated with DNA sequence specificity. Overall, this study demonstrated that K65R and K65R/Q151M related drug resistance to FTC and 3TC was mainly due to a significant decrease in the rate of incorporation. There was little to no effect on the binding affinities of the mutant HIV-1 RTs for the deoxycytidine analogues. The Q151M mutation remained sensitive to both FTC and 3TC in both cell culture and enzymatic assays. At a molecular level, FTC-TP was incorporated at least as efficiently as 3TC-TP for all of the HIV-1 RT and primer/templates tested.
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Affiliation(s)
- Joy Y Feng
- Gilead Sciences, Inc., Durham, North Carolina, USA.
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Alvarez K, Deval J, Selmi B, Barral K, Boretto J, Guerreiro C, Mulard L, Sarfati R, Canard B. Borano-nucleotides: new analogues to circumvent HIV-1 RT-mediated nucleoside drug-resistance. Nucleosides Nucleotides Nucleic Acids 2005; 24:419-21. [PMID: 16247962 DOI: 10.1081/ncn-200059951] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Alpha-boranophosphates suppress RT-mediated resistance when the catalytic rate of incorporation (kpol) of the analogue 5'-triphosphate is responsable for drug resistance, such as in the case of K65R mutant and ddNTPs, and Q151M toward AZTTP and ddNTPs. This suppression is also observed with BH3-d4T and BH3-3TC toward their clinically relevant mutants Q151M and M184V. Moreover, the presence of the borano (BH3-) group renders the incorporation of the analogue independent from amino-acid substitutions in RT. To our knowledge, this is the first example of rescue of polymerase activity by means of a nucleotide analogue.
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Affiliation(s)
- Karine Alvarez
- CNRS, UMR 6098, Architecture et Fonction des Macromolecules Biologiques, Marseille Cedex 9, France
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31
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Feng JY, Myrick F, Selmi B, Deval J, Canard B, Borroto-Esoda K. Effects of HIV Q151M-associated multi-drug resistance mutations on the activities of (−)-β-d-1′,3′-dioxolan guanine. Antiviral Res 2005; 66:153-8. [PMID: 15885814 DOI: 10.1016/j.antiviral.2005.03.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2004] [Revised: 03/15/2005] [Accepted: 03/15/2005] [Indexed: 11/23/2022]
Abstract
The multi-drug resistance HIV-1 genotype A62V/V75I/F77L/F116Y/Q151M is associated with resistance to many nucleoside reverse transcriptase inhibitors including AZT, ddI, ddC, d4T, abacavir, and 3TC. In this study, we evaluated the antiviral activity of (-)-beta-D-1',3'-dioxolan guanine (DXG) towards mutant HIV-1 containing V75I/F77L/F116Y/Q151M (V75Icomplex) and A62V/V75I/F77L/F116Y/Q151M (A62Vcomplex) in MT-2 cells. We further investigated the mechanism of resistance by studying the incorporation of DXG 5'-triphosphate (DXG-TP) during DNA synthesis by mutant enzymes containing single mutations at Q151M or A62V, and the V75Icomplex and A62Vcomplex using pre-steady state kinetic analysis. Our studies showed that mutant virus containing V75Icomplex and A62Vcomplex were both more than 23-fold resistant to DXG, and this correlated with the 68- and 20-fold resistance changes observed in the enzymatic assay. Compared to the wild-type enzyme, DXG-TP was incorporated 39- and 21-fold less efficiently by the mutant enzyme containing V75Icomplex and A62Vcomplex, mainly due to decreases in the rate of incorporation. The A62V mutation significantly increased the rate of incorporation (k(pol)) for both dGTP (3-fold) and DXG-TP (7.9-fold), while the binding affinity of A62V HIV-1 RT for DXG-TP was decreased 14-fold. At the enzyme level, the addition of the A62V mutation to V75I/F77L/F116Y/Q151M moderately (3.4-fold) reversed the resistance to DXG-TP.
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Affiliation(s)
- Joy Y Feng
- Gilead Science, 4 University Place, 4611 University Drive, Durham, NC 27707, USA.
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Deval J, Courcambeck J, Selmi B, Boretto J, Canard B. Structural determinants and molecular mechanisms for the resistance of HIV-1 RT to nucleoside analogues. Curr Drug Metab 2005; 5:305-16. [PMID: 15320702 DOI: 10.2174/1389200043335478] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The reverse transcriptase (RT) of human immunodeficiency virus type-1 (HIV-1) is an RNA- and DNA-dependent DNA polymerase capable of copying the viral genome before it gets integrated into the human host DNA. Hence, HIV-1 RT plays a major role in viral replication and represents a key target for anti-AIDS treatments. Amongst the eleven licensed drugs that inhibit RT, eight are chain-terminating nucleoside analogues (NRTIs) that compete with their natural counterparts during the DNA polymerization process. Unfortunately, under therapeutic pressure, the HIV-1 inevitably develops resistance to these inhibitors by accumulating mutations in the viral pol gene encoding RT. Mechanisms for this resistance can be sorted in two categories, depending on the nature of the drug and the selected mutations. The first category includes mutations involving a specific alteration of the discrimination between natural nucleotides and NRTIs. The second category includes mutations able to promote the removal of the incorporated NRTI and thus repair the nascent DNA chain. This review summarizes the modes of inhibition of HIV-1 RT with NRTIs, and describes the mechanisms of resistance to these drugs, based on enzymatic data correlated to crystal structures and molecular models involving HIV-1 RT. We also give insights into different aspects of resistance such as antagonistic mutations, replication capacity, and the implications for a rational, structure-based drug design.
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Affiliation(s)
- J Deval
- Centre National de la Recherche Scientifique et Université d'Aix-Marseille I and II, UMR 6098, Architecture et Fonction des Macromolécules Biologiques, ESIL-Case 925, 163 avenue de Luminy, 13288 Marseille Cedex 9, France
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Deval J, Alvarez K, Selmi B, Bermond M, Boretto J, Guerreiro C, Mulard L, Canard B. Mechanistic insights into the suppression of drug resistance by human immunodeficiency virus type 1 reverse transcriptase using alpha-boranophosphate nucleoside analogs. J Biol Chem 2004; 280:3838-46. [PMID: 15550379 DOI: 10.1074/jbc.m411559200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A class of amino acid substitutions in drug-resistant HIV-1 reverse transcriptase (RT) is responsible for the selectively impaired incorporation of the nucleotide analog inhibitor into DNA. We have shown previously that alpha-boranophosphate nucleoside analogs suppress RT-mediated resistance when the catalytic rate is responsible for drug resistance such as in the case of K65R and dideoxy (dd)NTPs, and Q151M toward AZTTP and ddNTPs. Here, we extend this property to BH3-d4TTP and BH3-3TCTP toward their clinically relevant mutants Q151M and M184V, respectively. Pre-steady-state kinetics on mutants of the Q151M RT family reveal a 3-5-fold resistance to d4TTP. This resistance is suppressed using BH3-d4TTP. Likewise, resistance to 3TCTP by M184V RT (30-fold) and K65R/M184V RT (180-fold) is suppressed using BH3-3TCTP because of a 160-fold acceleration of the catalytic constant kpol. Mechanistic insights into the rate enhancement were obtained using various alpha-boranophosphate nucleotides. The presence of the BH3 group renders kpol independent of amino acid substitutions present in RT. Indeed, the approximately 100-fold decrease in polymerase activity caused by the R72A substitution is restored to wild-type levels using BH3-dTTP. Metal ion titration studies show that alpha-boranophosphate nucleoside analogs enhance 3-8-fold the binding of Mg2+ ions to the active site of the RT.DNA.dNTP complex and alleviate the requirement of critical amino acids involved in phosphodiester bond formation. To our knowledge, this is the first example of rescue of polymerase activity by means of a nucleotide analog.
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Affiliation(s)
- Jérôme Deval
- CNRS and Universités d'Aix-Marseille I et II, UMR 6098, Architecture et Fonction des Macromolécules Biologiques, ESIL-Case 925, 163 avenue de Luminy, 13288 Marseille cedex 9, France
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Deval J, Navarro JM, Selmi B, Courcambeck J, Boretto J, Halfon P, Garrido-Urbani S, Sire J, Canard B. A loss of viral replicative capacity correlates with altered DNA polymerization kinetics by the human immunodeficiency virus reverse transcriptase bearing the K65R and L74V dideoxynucleoside resistance substitutions. J Biol Chem 2004; 279:25489-96. [PMID: 15044478 DOI: 10.1074/jbc.m313534200] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mechanisms governing viral replicative capacity are poorly understood at the biochemical level. Human immunodeficiency virus, type 1 reverse transcriptase (HIV-1 RT) K65R or L74V substitutions confer viral resistance to 2',3'-dideoxyinosine (ddI) in vivo. The two substitutions never occur together, and L74V is frequently found in patients receiving ddI, while K65R is not. Here we show that recombinant viruses carrying K65R and K65R/L74V display the same resistance level to ddI (about 9.5-fold) relative to wild type. Consistent with this result, purified HIV-1 RT carrying K65R RT or K65R/L74V substitutions exhibits an 8-fold resistance to ddATP as judged by pre-steady state kinetics of incorporation of a single nucleotide into DNA. Resistance is due to a selective decrease of the catalytic rate constant k(pol): 22-fold (from 7.2 to 0.33 s(-1)) for K65R RT and 84-fold (from 7.2 to 0.086 s(-1)) for K65R/L74V RT. However, the K65R/L74V virus replication capacity is severely impaired relative to that of wild-type virus. This loss of viral fitness is correlated to a poor ability of K65R/L74V RT to use natural nucleotides relative to wild-type RT: 15% that of wild-type RT for dATP, 36% for dGTP, 50% for dTTP, and 25% for dCTP. The order of incorporation efficiency is wild-type RT > L74V RT > K65R RT > K65R/L74V RT. Processivity of DNA synthesis remains unaffected. These results explain why the two mutations do not combine in the clinic and might give a mechanism for a decreased viral fitness at the molecular level.
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Affiliation(s)
- Jérôme Deval
- CNRS and Universités d'Aix-Marseille I et II, UMR 6098, Architecture et Fonction des Macromolécules Biologiques, Ecole Supérieure d'Ingénieurs de Luminy-Case 925, Marseille, France
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Selmi B, Deval J, Alvarez K, Boretto J, Sarfati S, Guerreiro C, Canard B. The Y181C substitution in 3'-azido-3'-deoxythymidine-resistant human immunodeficiency virus, type 1, reverse transcriptase suppresses the ATP-mediated repair of the 3'-azido-3'-deoxythymidine 5'-monophosphate-terminated primer. J Biol Chem 2003; 278:40464-72. [PMID: 12902345 DOI: 10.1074/jbc.m302928200] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Resistance to zidovudine (3'-azido-3'-deoxythymidine, AZT) by the human immunodeficiency virus, type 1, requires multiple amino acid substitutions such as D67N/K70R/T215F/K219Q in the viral reverse transcriptase (RT). In this background of AZT resistance, additional "suppressive" substitutions such as Y181C restore sensitivity to AZT. In order to characterize the mechanism of this AZT resistance suppression, the Y181C substitution was introduced into both wild-type and AZT-resistant reverse transcriptase. The introduction of the Y181C substitution suppresses the increased repair (or unblocking) of the AZTMP-terminated primer provided by the AZT resistance substitutions in RT using either DNA or RNA templates, independently from the RT RNase H activity. Contrary to wild-type RT, the low level of unblocking activity is not due to inhibition by the next correct nucleotide binding to the RT/AZTMP-terminated primer complex. When Y181C is added to the AZT resistance substitutions, ATP binds with less affinity to the AZTMP-terminated primer-RT binary complex. These results provide an insight into one possible molecular mechanism of re-sensitization of AZT-resistant viruses by suppressive substitutions.
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Affiliation(s)
- Boulbaba Selmi
- CNRS and Universités d'Aix-Marseille I and II, UMR 6098, Architecture et Fonction des Macromolécules Biologiques, ESIL-Case 925, 163 Avenue de Luminy, 13288 Marseille Cedex 09, France
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Deval J, White KL, Miller MD, Parkin NT, Courcambeck J, Halfon P, Selmi B, Boretto J, Canard B. Mechanistic basis for reduced viral and enzymatic fitness of HIV-1 reverse transcriptase containing both K65R and M184V mutations. J Biol Chem 2003; 279:509-16. [PMID: 14551187 DOI: 10.1074/jbc.m308806200] [Citation(s) in RCA: 137] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
HIV-1 drug resistance mutations are often inversely correlated with viral fitness, which remains poorly described at the molecular level. Some resistance mutations can also suppress resistance caused by other resistance mutations. We report the molecular mechanisms by which a virus resistant to lamivudine with the M184V reverse transcriptase mutation shows increased susceptibility to tenofovir and can suppress the effects of the tenofovir resistance mutation K65R. Additionally, we report how the decreased viral replication capacity of resistant viruses is directly linked to their decreased ability to use natural nucleotide substrates and that combination of the K65R and M184V resistance mutations leads to greater decreases in viral replication capacity. All together, these results define at the molecular level how nucleoside-resistant viruses can be driven to reduced viral fitness.
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Affiliation(s)
- Jérôme Deval
- Architecture et Fonction des Macromolécules Biologiques, UMR 6098 CNRS et Université Aix-Marseille I et II, ESIL, Campus de Luminy, 13288 Marseille cedex 09, France
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Selmi B, Deval J, Boretto J, Canard B. Nucleotide analogue binding, catalysis and primer unblocking in the mechanisms of HIV-1 reverse transcriptase-mediated resistance to nucleoside analogues. Antivir Ther 2003; 8:143-54. [PMID: 12741627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
Nucleoside analogues play a key role in the fight against HIV-1. Unfortunately, under therapeutic pressure, HIV-1 inevitably develops resistance to these inhibitors. This resistance correlates with specific pol gene mutations giving rise to specific substitutions in reverse transcriptase that are responsible for the loss of efficacy of the corresponding analogue. This work is an overview of the molecular mechanisms of HIV-1 drug resistance as judged by the analysis of chemical reactions at play at the reverse transcriptase active site. One class of mechanism involves nucleotide analogue discrimination either at the binding step or at the catalytic step, the latter being by far the most common mechanism. The other class of mechanism involves repair of the analogue-terminated DNA chain. The mechanisms were elucidated using purified reverse transcriptase and biochemical assays aimed at correlating resistant HIV-1 phenotypes to enzymatic data. The elucidation of these molecular mechanisms of drug-resistant reverse transcriptase is important for effective and rational combination therapies as well as for the conception of second-generation drugs that do not confer nucleotide resistance to reverse transcriptase or are active against pre-existing resistant viruses.
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Affiliation(s)
- Boulbaba Selmi
- Centre National de la Recherche Scientifique et Université d'Aix-Marseille I and II, UMR 6098, Architecture et Fonction des Macromolécules Biologiques, ESIL-Case 925, 163 avenue de Luminy, 13288 Marseille cedex 9, France
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Selmi B, Deval J, Boretto J, Canard B. Nucleotide Analogue Binding, Catalysis and Primer Unblocking in the Mechanisms of HIV-1 Reverse Transcriptase-Mediated Resistance to Nucleoside Analogues. Antivir Ther 2003. [DOI: 10.1177/135965350300800209] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Nucleoside analogues play a key role in the fight against HIV-1. Unfortunately, under therapeutic pressure, HIV-1 inevitably develops resistance to these inhibitors. This resistance correlates with specific pol gene mutations giving rise to specific substitutions in reverse transcriptase that are responsible for the loss of efficacy of the corresponding analogue. This work is an overview of the molecular mechanisms of HIV-1 drug resistance as judged by the analysis of chemical reactions at play at the reverse transcriptase active site. One class of mechanism involves nucleotide analogue discrimination either at the binding step or at the catalytic step, the latter being by far the most common mechanism. The other class of mechanism involves repair of the analogue-terminated DNA chain. The mechanisms were elucidated using purified reverse transcriptase and biochemical assays aimed at correlating resistant HIV-1 phenotypes to enzymatic data. The elucidation of these molecular mechanisms of drug-resistant reverse transcriptase is important for effective and rational combination therapies as well as for the conception of second-generation drugs that do not confer nucleotide resistance to reverse transcriptase or are active against pre-existing resistant viruses.
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Affiliation(s)
- Boulbaba Selmi
- Centre National de la Recherche Scientifique et Université d'Aix-Marseille I and II, UMR 6098, Architecture et Fonction des Macromolécules Biologiques, ESIL-Case 925, 163 avenue de Luminy, 13288 Marseille cedex 9, France
| | - Jérôme Deval
- Centre National de la Recherche Scientifique et Université d'Aix-Marseille I and II, UMR 6098, Architecture et Fonction des Macromolécules Biologiques, ESIL-Case 925, 163 avenue de Luminy, 13288 Marseille cedex 9, France
| | - Joëlle Boretto
- Centre National de la Recherche Scientifique et Université d'Aix-Marseille I and II, UMR 6098, Architecture et Fonction des Macromolécules Biologiques, ESIL-Case 925, 163 avenue de Luminy, 13288 Marseille cedex 9, France
| | - Bruno Canard
- Centre National de la Recherche Scientifique et Université d'Aix-Marseille I and II, UMR 6098, Architecture et Fonction des Macromolécules Biologiques, ESIL-Case 925, 163 avenue de Luminy, 13288 Marseille cedex 9, France
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Deval J, Selmi B, Boretto J, Egloff MP, Guerreiro C, Sarfati S, Canard B. The molecular mechanism of multidrug resistance by the Q151M human immunodeficiency virus type 1 reverse transcriptase and its suppression using alpha-boranophosphate nucleotide analogues. J Biol Chem 2002; 277:42097-104. [PMID: 12194983 DOI: 10.1074/jbc.m206725200] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Nucleoside analogues are currently used to treat human immunodeficiency virus infections. The appearance of up to five substitutions (A62V, V75I, F77L, F116Y, and Q151M) in the viral reverse transcriptase promotes resistance to these drugs, and reduces efficiency of the antiretroviral chemotherapy. Using pre-steady state kinetics, we show that Q151M and A62V/V75I/F77L/F116Y/Q151M substitutions confer to reverse transcriptase (RT) the ability to discriminate an analogue relative to its natural counterpart, and have no effect on repair of the analogue-terminated DNA primer. Discrimination results from a selective decrease of the catalytic rate constant k(pol): 18-fold (from 7 to 0.3 s(-1)), 13-fold (from 1.9 to 0.14 s(-1)), and 12-fold (from 13 to 1 s(-1)) in the case of ddATP, ddCTP, and 3'-azido-3'-deoxythymidine 5'-triphosphate (AZTTP), respectively. The binding affinities of the triphosphate analogues for RT remain unchanged. Molecular modeling explains drug resistance by a selective loss of electrostatic interactions between the analogue and RT. Resistance was overcome using alpha-boranophosphate nucleotide analogues. Using A62V/V75I/F77L/F116Y/Q151M RT, k(pol) increases up to 70- and 13-fold using alpha-boranophosphate-ddATP and alpha-boranophosphate AZTTP, respectively. These results highlight the general capacity of such analogues to circumvent multidrug resistance when RT-mediated nucleotide resistance originates from the selective decrease of the catalytic rate constant k(pol).
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Affiliation(s)
- Jerome Deval
- Centre National de la Recherche Scientifique and Universités d'Aix-Marseille I et II, UMR 6098, Architecture et Fonction des Macromolécules Biologiques, ESIL-Case 925, 163 avenue de Luminy, 13288 Marseille cedex 9, France
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Selmi B, Boretto J, Sarfati SR, Guerreiro C, Canard B. Mechanism-based suppression of dideoxynucleotide resistance by K65R human immunodeficiency virus reverse transcriptase using an alpha-boranophosphate nucleoside analogue. J Biol Chem 2001; 276:48466-72. [PMID: 11606579 DOI: 10.1074/jbc.m107003200] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The amino acid change K65R in human immunodeficiency virus type 1-reverse transcriptase (RT) confers viral resistance to various 2',3'-dideoxynucleoside drugs in vivo. Using pre-steady state kinetic methods, we found that K65R-reverse transcriptase is 3.2-14-fold resistant to 2',3'-dideoxynucleotides in vitro relative to wild-type reverse transcriptase, in agreement with resistance levels observed in vivo. A decreased catalytic rate constant k(pol) mostly accounts for the lower incorporation efficiency observed for 2',3'-dideoxynucleotides. Examination of the crystal structure of the RT.DNA.dNTP complex suggested that both the charge at position 65 and the 3'-OH of the incoming nucleotide act in synergy during the creation of the phosphodiester bond, resulting in a more pronounced decreased catalytic rate constant for 2',3'-dideoxynucleotides than for dNTPs. This type of intramolecular activation of the leaving phosphate by the 3'-OH group appears to be conserved in several nucleotide phosphotransferases. These data were used to design dideoxynucleotide analogues targeting K65R RT specifically. alpha-Boranophosphate ddATP was found to be a 2-fold better substrate than dATP and inhibited DNA synthesis by K65R RT 153-fold better than ddATP. This complete suppression of drug resistance at the nucleotide level could serve for other reverse transcriptases for which drug resistance is achieved at the catalytic step.
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Affiliation(s)
- B Selmi
- Centre National de la Recherche Scientifique and Universités d'Aix-Marseille I et II, UMR 6098, Architecture et Fonction des Macromolécules Biologiques, ESIL-Case 925, 163 avenue de Luminy, 13288 Marseille cedex 9, France
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Boretto J, Longhi S, Navarro JM, Selmi B, Sire J, Canard B. An integrated system to study multiply substituted human immunodeficiency virus type 1 reverse transcriptase. Anal Biochem 2001; 292:139-47. [PMID: 11319828 DOI: 10.1006/abio.2001.5045] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We describe a gene system allowing the facile production of multiply substituted reverse transcriptases (RTs), the enzymatic characterization of these purified RTs, and the study of these mutations in the defined genetic background of the macrophagetropic, non-laboratory-adapted human immunodeficiency virus type 1 (HIV-1) AD8 strain. Thirteen unique silent restriction sites were introduced in the pol gene encoding HIV-1 RT, allowing easy introduction of mutations. To simplify genetic manipulation and generate p66/p51 heterodimers in Escherichia coli, a gene construct of the viral protease alone was optimized for expression from a separate vector carrying a p15A origin of replication. Active-site titration experiments using pre-steady-state kinetics showed that our system yields a higher proportion of active enzyme than that obtained by alternate methods. To facilitate phenotype/genotype correlations, the modified RT gene was designed to be easily reintroduced into a recombinant proviral AD8 HIV-1 DNA. Infectious viruses made from this vector were undistinguishable from wild-type AD8 HIV-1, an isolate able to infect peripheral blood mononuclear cells and macrophages. Thus, the pol gene can tolerate many silent mutations in the polymerase domain without affecting the functionality of the HIV-1 genome. The system was validated biochemically and virologically using the V75T substitution associated with stavudine resistance.
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Affiliation(s)
- J Boretto
- Architecture et Fonction des Macromolécules Biologiques (AFMB), UMR 6098, CNRS, Universités d'Aix-Marseille I et II, 163 Avenue de Luminy, Marseille Cedex 09, F-13288, France
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Selmi B, Boretto J, Navarro JM, Sire J, Longhi S, Guerreiro C, Mulard L, Sarfati S, Canard B. The valine-to-threonine 75 substitution in human immunodeficiency virus type 1 reverse transcriptase and its relation with stavudine resistance. J Biol Chem 2001; 276:13965-74. [PMID: 11134027 DOI: 10.1074/jbc.m009837200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The amino acid change V75T in human immunodeficiency virus type 1 reverse transcriptase confers a low level of 2',3'-didehydro-2',3'-dideoxythymidine (stavudine, d4T) resistance in vivo and in vitro. Valine 75 is located at the basis of the fingers subdomain of reverse transcriptase between the template contact point and the nucleotide-binding pocket. V75T reverse transcriptase discriminates 3.6-fold d4T 5'-triphosphate relative to dTTP, as judged by pre-steady state kinetics of incorporation of a single nucleotide into DNA. In addition, V75T increases the DNA polymerization rate up to 5-fold by facilitating translocation along nucleic acid single-stranded templates. V75T also increases the reverse transcriptase-mediated repair of the d4TMP-terminated DNA by pyrophosphate but not by ATP. The V75T/Y146F double substitution partially suppressed both increases in rate of polymerization and pyrophosphorolysis, indicating that the hydroxyl group of Thr-75 interacts with that of Tyr-146. V75T recombinant virus was 3-4-fold d4T-resistant and 3-fold resistant to phosphonoformic acid relative to wild type, confirming that the pyrophosphate traffic is affected in V75T reverse transcriptase. Thus, in addition to nucleotide selectivity V75T defines a type of amino acid change conferring resistance to nucleoside analogues that links translocation rate to the traffic of pyrophosphate at the reverse transcriptase active site.
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Affiliation(s)
- B Selmi
- CNRS and Universités d'Aix-Marseille I and II, UMR 6098, Architecture et Fonction des Macromolécules Biologiques, ESIL-Case 925, 13288 Marseille Cedex 9, France
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Lazaro JB, Boretto J, Selmi B, Capony JP, Canard B. Phosphorylation of AZT-resistant human immunodeficiency virus type 1 reverse transcriptase by casein kinase II in vitro: effects on inhibitor sensitivity. Biochem Biophys Res Commun 2000; 275:26-32. [PMID: 10944435 DOI: 10.1006/bbrc.2000.3251] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Casein kinase II (CKII) phosphorylates wild-type (WT) recombinant reverse transcriptase (RT) mainly in the p66 subunit in vitro. Phosphorylation of T215F RT and D67N/K70R/T215F/K219Q RT (AZT-resistant RT) in vitro increases discrimination against AZTTP 2. 5- and 3.6-fold, respectively. This in vitro resistance can be reversed by treatment of phosphorylated AZT-resistant RT with phosphatase. Phosphorylation has no effect on WT RT. Terminal transferase activity of RT is selectively suppressed on phosphorylated AZT-resistant RT. Resistance to phosphonoformic acid (PFA, foscarnet) increases 3-fold upon phosphorylation of AZT-resistant RT. Although T215, the most important residue for AZT-resistance, is part of a CKII consensus target site, serines are primarily phosphorylated relative to threonines. Mutational analysis shows that phosphorylation can be reduced to 10% that of WT when amino-acid changes are introduced both in the "fingers" subdomain and motif D. These results suggest that phosphorylation of RT might be one factor involved in drug resistance in vivo.
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Affiliation(s)
- J B Lazaro
- Department BCMP, Harvard Medical School, Boston, Massachusetts, USA
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Selmi B, Marion D, Perrier Cornet JM, Douzals JP, Gervais P. Amyloglucosidase hydrolysis of high-pressure and thermally gelatinized corn and wheat starches. J Agric Food Chem 2000; 48:2629-2633. [PMID: 11032475 DOI: 10.1021/jf991332u] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The study of glucose production using amyloglucosidase as a biocatalyst was carried out using high-pressure and thermally gelatinized corn and wheat starches. For corn starch, the measured initial rate of glucose production obtained from thermal gelatinization is faster than that obtained from the two high-pressure treatments, but the equilibrium yield of glucose was found to be similar for the three treatments. High-pressure treatments of wheat starch significantly improve the equilibrium yield of glucose compared with those obtained from the thermally gelatinized wheat starch. This difference has been related to the formation of amylose-lipid complexes during heating and could also explain previous physicochemical differences observed between high-pressure and thermally gelatinized starch.
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Affiliation(s)
- B Selmi
- Laboratoire de Génie des Procédés Alimentaires et Biotechnologiques, ENSBANA, 21000 Dijon, France
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Selmi B, Gontier E, Ergan F, Thomas D. Effects of fatty acid chain length and unsaturation number on triglyceride synthesis catalyzed by immobilized lipase in solvent-free medium. Enzyme Microb Technol 1998. [DOI: 10.1016/s0141-0229(98)00022-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Selmi B, Gontier E, Ergan F, Barbotin J, Thomas D. Lipase-catalyzed synthesis of tricaprylin in a medium solely composed of substrates. Water production and elimination. Enzyme Microb Technol 1997. [DOI: 10.1016/s0141-0229(96)00132-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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