Displaying publications 1 - 20 of 35 in total

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  1. Majeed QA, Alshammari A, Alanazi AD
    Trop Biomed, 2023 Jun 01;40(2):259-265.
    PMID: 37650415 DOI: 10.47665/tb.40.2.019
    Leishmaniasis is an infectious disease with various clinical manifestations. We studied the therapeutic effects of Elettaria cardamomum essential oil (ECEO) against Leishmania major infection. In vitro effects of ECEO against L. major were examined by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and macrophage assays. Nitric oxide (NO) production, infection inhibition in macrophages, and the apoptotic activity of ECEO in treated parasites were also measured. By calculating the 50% cytotoxic concentrations (CC50), we studied the cytotoxicity effects of ECEO on human macrophage cells (THP-1). The efficacy of ECEO for improving cutaneous leishmaniasis (CL) lesions in mice (BALB/c) was determined by evaluating the size of lesions and the number of amastigotes before and after four weeks of treatment. The effects of ECEO on liver and kidney function in the tested mice were also evaluated. ECEO dose-dependently (p<0.001) inhibited the viability and the mean number of promastigotes and amastigote forms of L. tropica. Four weeks of treatment with ECEO at the doses of 2.5 and 5 mg/kg/ day significantly (p<0.001) improved the CL lesions and reduced the number of parasites in the infected mice. ECEO significantly increased NO production, apoptosis induction, and infection rate in parasites. The CC50 value for ECEO and MA was 303.4 µg/mL and 835.2 µg/mL, respectively. In the mice receiving ECEO at the doses of 2.5 and 5 mg/kg/day for 28 days, no significant change was reported between the serum level of liver enzymes and kidney factors when compared with the control group. ECEO displayed promising efficacy in parasite reduction in vitro and in the animal model. ECEO can thus be used as an alternative medicine to treat CL.
    Matched MeSH terms: Leishmania major*
  2. Alamin AA, Gebreyesus MW, Mohamed I
    Trop Biomed, 2023 Jun 01;40(2):250-252.
    PMID: 37650413 DOI: 10.47665/tb.40.2.017
    Leishmaniasis is a widely spread zoonotic disease caused by the bite of infected sandflies, particularly in developing countries. Cutaneous leishmaniasis can have a diverse range of presentations, ranging from minor skin nodules to significant mucosal damage. However, nose involvement is infrequent. Our report highlights a 15-year-old female patient with a persistent skin lesion on her nose for three months, which is a rare manifestation of cutaneous leishmaniasis. The lesion started as a raised spot with a brownish-red color and a crust but eventually developed into an ulcer that spread over the entire lobe of the nose and even moved toward the eye. Microscopic examination revealed the presence of Leishmania amastigotes, and a biopsy confirmed a diagnosis of cutaneous leishmaniasis. The patient received daily intravenous sodium stibogluconate doses of 9 mg/kg for 20 days, and three weeks later, there was a significant clinical improvement, with the ulcer beginning to heal and no more amastigotes visible on microscopic examination. It is crucial to keep cutaneous leishmaniasis in mind as a possible diagnosis for patients with skin lesions, even in regions where the condition is not prevalent.
    Matched MeSH terms: Leishmania*
  3. Khan RU, Khan M, Sohail A, Ullah R, Iqbal A, Ahmad B, et al.
    Trop Biomed, 2022 Dec 01;39(4):511-517.
    PMID: 36602209 DOI: 10.47665/tb.39.4.003
    The present study compares the in vitro effects of nanoparticles loaded pentamidine drug and conventional pentamidine on Leishmania tropica. Herein, pentamidine-loaded chitosan nanoparticles (PTN-CNPs) have been synthesized through an ionic gelation method with sodium tripolyphosphate (TPP). Next, the physical characteristics of PTN-CNPs were determined through the surface texture, zeta potential, in vitro drug release, drug loading content (DLC), and encapsulation efficacy (EE) and compared its efficacy with free pentamidine (PTN) drug against promastigotes and axenic amastigotes forms of L. tropica in vitro. The PTN-CNPs displayed a spherical shape having a size of 88 nm, an almost negative surface charge (-3.09 mV), EE for PTN entrapment of 86%, and in vitro drug release of 92% after 36 h. In vitro antileishmanial activity of PTN-CNPs and free PTN was performed against Leishmania tropica KWH23 promastigote and axenic amastigote using 3-(4, 5- dimethylthiazol-2-yl)-2, 5-diphenyletetrazolium bromide (MTT) assay. It was observed that the effect of PTN-CNPs and free PTN on both forms of the parasite was dose and time dependent. Free PTN presented low efficacy even at higher dose (40 µg/ml) with 25.6 ± 1.3 and 26.5 ±1.4 mean viability rate of the promastigotes and axenic amastigotes, respectively after 72 hrs incubation. While PTN-CNPs showed strong antileishmanial effects on both forms of parasite with 16 ± 0.4 and 19 ± 0.7 mean viability rate at the same higher concentration (40 µg/ml) after 72 hrs incubation. Half maximal inhibitory concentration (IC50) values of PTN-CNPs toward promastigotes and amastigotes were obtained as 0.1375 µg/ml and 0.1910 µg/ml, respectively. In conclusion, PTN-CNPs effectively inhibited both forms of the L. tropica; however, its effect was more salient on promastigotes. This data indicates that the PTN-CNPs act as a target drug delivery system. However, further research is needed to support its efficacy in animal and human CL.
    Matched MeSH terms: Leishmania tropica*
  4. Hustedt J, Prasetyo DB, Fiorenzano JM, von Fricken ME, Hertz JC
    Parasit Vectors, 2022 Oct 05;15(1):355.
    PMID: 36199150 DOI: 10.1186/s13071-022-05464-8
    Phlebotomine sand flies are proven or suspected vectors of several pathogens of importance, including leishmaniasis, bartonellosis and sand fly fevers. Although sand flies have a worldwide distribution, there has been limited research published on sand flies and sand fly-borne pathogens throughout the Greater Mekong Sub-region (GMS). This review followed the PRISMA guidelines to determine the biodiversity and presence of phlebotomine sand flies and their associated pathogens in the GMS, specifically Cambodia, Thailand, the Lao People's Democratic Republic (Laos), Malaysia and Vietnam. A total of 1472 records were identified by searching electronic databases, scanning reference lists of articles and consulting experts in the field. After screening of title and abstracts, 178 records remained and were further screened for original data (n = 34), not having regional data (n = 14), duplication of data (n = 4), records not available (n = 4) and no language translation available (n = 2). A total of 120 studies were then included for full review, with 41 studies on sand fly-related disease in humans, 33 studies on sand fly-related disease in animals and 54 entomological studies focused on sand flies (5 papers contained data on > 1 category), with a majority of the overall data from Thailand. There were relatively few studies on each country, with the exception of Thailand, and the studies applied different methods to investigate sand flies and sand fly-borne diseases, impacting the ability to conduct meaningful meta-analysis. The findings suggest that leishmaniasis in humans and the presence of sand fly vectors have been reported across several GMS countries over the past 100 years, with local transmission in humans confirmed in Thailand and Vietnam. Additionally, local Mundinia species are likely transmitted by biting midges. Findings from this study provide a framework for future investigations to determine the geographic distribution and risk profiles of leishmaniasis and other associated sand fly-borne disease throughout the GMS. It is recommended that researchers expand surveillance efforts across the GMS, with an emphasis placed on entomological surveys, syndromic and asymptomatic monitoring in both humans and animals and molecular characterization of sand flies and sand fly-borne pathogens, particularly in the understudied countries of Cambodia, Vietnam and Laos.
    Matched MeSH terms: Leishmania*
  5. Levaique H, Pamlard O, Apel C, Bignon J, Arriola M, Kuhner R, et al.
    Molecules, 2021 Mar 11;26(6).
    PMID: 33799883 DOI: 10.3390/molecules26061551
    Leishmaniasis is a vector-borne disease caused by the protozoan parasite Leishmania found in tropical and sub-tropical areas, affecting 12 million people around the world. Only few treatments are available against this disease and all of them present issues of toxicity and/or resistance. In this context, the development of new antileishmanial drugs specifically directed against a therapeutic target appears to be a promising strategy. The GDP-Mannose Pyrophosphorylase (GDP-MP) has been previously shown to be an attractive therapeutic target in Leishmania. In this study, a chemical library of 5000 compounds was screened on both L. infantum (LiGDP-MP) and human (hGDP-MP) GDP-MPs. From this screening, oncostemonol D was found to be active on both GDP-MPs at the micromolar level. Ten alkyl-resorcinol derivatives, of which oncostemonols E and J (2 and 3) were described for the first time from nature, were then evaluated on both enzymes as well as on L. infantum axenic and intramacrophage amastigotes. From this evaluation, compounds 1 and 3 inhibited both GDP-MPs at the micromolar level, and compound 9 displayed a three-times lower IC50 on LiGDP-MP, at 11 µM, than on hGDP-MP. As they displayed mild activities on the parasite, these compounds need to be further pharmacomodulated in order to improve their affinity and specificity to the target as well as their antileishmanial activity.
    Matched MeSH terms: Leishmania/drug effects; Leishmania/pathogenicity; Leishmaniasis/drug therapy*
  6. Zahedi SN, Hejazi SH, Boshtam M, Amini F, Fazeli H, Sarmadi M, et al.
    Acta Parasitol, 2021 Mar;66(1):53-59.
    PMID: 32676917 DOI: 10.1007/s11686-020-00251-w
    PURPOSE: Leishmaniasis, a widespread parasitic disease, is a public health concern that is endemic in more than 90 countries. Owing to the drug resistance and also undesirable complications, designing new therapeutic methods are essential. C-reactive protein (CRP) is an acute phase protein of plasma with several immune modulatory functions. This study aimed to evaluate the effect of human recombinant CRP (hrCRP) on treating cutaneous leishmaniasis in mice models.

    METHODS: hrCRP was expressed in E. coli Rosetta-gami and extracted from the SDS-PAGE gel. Male BALB/c mice were inoculated subcutaneously at the base of their tails by 1 × 105 stationary-phase of Leishmania major promastigotes (MHRO/IR/75/ER) suspended in sterile phosphate buffered saline (PBS). Nodules and subsequently, ulcers developed 14 days post-injection. 1.5 µg of the purified protein was administered on lesions of pre-infected mice by Leishmania major in the intervention group for five consecutive days.

    RESULTS: The mean area of the lesions was decreased by about seven folds in the intervention group as compared to the control group after two weeks of the treatment (p = 0.024). The results were verified by the real-time polymerase chain reaction so that the parasite burden was determined 27 times in the control group as compared to the intervention group (p = 0.02). Two weeks after treatment, the conversion of the lesions to scars in the intervention group was observed.

    CONCLUSION: The results indicate a potential therapeutic role for hrCRP in improving cutaneous leishmaniasis due to Leishmania major in mice models. The healing was in a stage-dependent manner.

    Matched MeSH terms: Leishmania major*
  7. Khan TA, Al Nasr IS, Mujawah AH, Koko WS
    Trop Biomed, 2021 Mar 01;38(1):135-141.
    PMID: 33797536 DOI: 10.47665/tb.38.1.023
    Leishmaniasis and toxoplasmosis are parasitic protozoal diseases that pose serious health concerns, especially for immunocompromised people. Leishmania major and Toxoplasma gondii are endemic in Saudi Arabia and are particularly common in the Qassim Region. The present work was conducted to evaluate the in vitro antileishmanial and antitoxoplasmal activity of methanolic extracts and phytochemical fractions from two plants, Euphorpia retusa and Pulicaria undulata, which are ethnobotanical agents used to treat parasitic infection. Whole E. retusa and P. undulata plants were extracted with methanol and fractionated using petroleum ether, chloroform, ethyl acetate, n-butanol, and water and then were tested in vitro against L. major promastigote and the amastigote stages of T. gondii; the cytotoxicity of the extracts was tested against Vero cell line. The methanolic extracts of E. retusa and P. undulata exhibited promising antitoxoplasmal activity against T. gondii with EC50 values 5.6 and 12.7 μg mL-1, respectively. The chloroform fraction of P. undulata was the most potent, exhibiting an EC50 of 1.4 μg mL-1 and SI value of 12.1. It was also the most active fraction against both L. major promastigotes and amastigotes, exhibiting an EC50 of 3.9 and 3.8 μg mL-1 and SI values 4.4 and 4.5, respectively. The chloroform fraction from P. undulata is a very good candidate for the isolation of active antitoxoplasmal and antileishmanial ingredients; therefore, further phytochemical analysis for active compound isolation is highly recommended.
    Matched MeSH terms: Leishmania major/drug effects*
  8. Procházková M, Füzik T, Grybchuk D, Falginella F, Podešvová L, Yurchenko V, et al.
    J Virol, 2020 Nov 18.
    PMID: 33208443 DOI: 10.1128/JVI.01957-20
    Leishmania parasites cause a variety of symptoms, including mucocutaneous leishmaniasis, which results in the destruction of the mucous membranes of the nose, mouth, and throat. The species of Leishmania carrying Leishmania RNA virus 1 (LRV1), from the family Totiviridae, are more likely to cause severe disease and are less sensitive to treatment than those that do not contain the virus. Although the importance of LRV1 for the severity of leishmaniasis was discovered a long time ago, the structure of the virus remained unknown. Here, we present a cryo-electron microscopy reconstruction of the virus-like particle of LRV1 determined to a resolution of 3.65 Å. The capsid has icosahedral symmetry and is formed by 120 copies of a capsid protein assembled in asymmetric dimers. RNA genomes of viruses from the family Totiviridae are synthetized, but not capped at the 5' end, by virus RNA-polymerases. To protect viral RNAs from degradation, capsid proteins of totivirus L-A cleave the 5' caps of host mRNAs, creating decoys to overload the cellular RNA quality control system. Capsid proteins of LRV1 form positively charged clefts, which may be the cleavage sites for the 5' cap of Leishmania mRNAs. Capsid proteins of LRV1 contain a putative RNA binding site distinct from that of the related L-A virus. The structure of the LRV1 capsid enables the rational design of compounds targeting the putative de-capping site. Such inhibitors may be developed into a treatment for mucocutaneous leishmaniasis caused by LRV1-positive species of LeishmaniaIMPORTANCE Twelve million people worldwide suffer from leishmaniasis, resulting in more than thirty thousand deaths annually. The disease has several variants that differ in their symptoms. The mucocutaneous form, which leads to disintegration of the nasal septum, lips, and palate, is predominantly caused by Leishmania parasites carrying Leishmania RNA virus 1 (LRV1). Here, we present the structure of the LRV1 capsid determined using cryo-electron microscopy. Capsid proteins of a related totivirus L-A protect viral RNAs from degradation by cleaving the 5' caps of host mRNAs. Capsid proteins of LRV1 may have the same function. We show that the LRV1 capsid contains positively charged clefts that may be sites for the cleavage of mRNAs of Leishmania cells. The structure of the LRV1 capsid enables the rational design of compounds targeting the putative mRNA cleavage site. Such inhibitors may be used as treatments for muco-cutaneous leishmaniasis.
    Matched MeSH terms: Leishmania; Leishmaniasis, Mucocutaneous; Leishmaniasis, Cutaneous; Leishmaniavirus
  9. Taha M, Sain AA, Ali M, Anouar EH, Rahim F, Ismail NH, et al.
    Bioorg Chem, 2020 06;99:103819.
    PMID: 32325334 DOI: 10.1016/j.bioorg.2020.103819
    Leishmaniasis has affected a wider part of population around the globe. Most often, the existing regiments to battle against leishmaniasis are inadequate and limited. In our ongoing efforts to develop new leishmanicidal agents, we have synthesized a series of novel and symmetrical bis-Schiff base-disulfide hybrids 1-27. Intermediate disulfide was synthesized from corresponding 2-aminothiol followed by reacting the coupled adduct with various aromatic aldehydes. All these compounds showed outstanding inhibition when compared with standard (Table 1). Out of twenty seven analogues, twenty two analogues i.e. 1-5, 7-13, 17-21, 23-27 analogues showed excellent inhibitory potential with EC50 values ranging from 0.010 ± 0.00 to 0.096 ± 0.01 μM while five compounds i.e. 6, 14-16, and 22 showed good inhibitory potential with EC50 values ranging from 0.10 ± 0.00 to 0.137 ± 0.01 μM when compared with the standard Amphotericin B. Structure-activity relationship has been established while molecular docking studies were performed to pin the binding interaction of active molecules. This study will help to develop new antileishmanial lead compounds.
    Matched MeSH terms: Leishmania/drug effects*
  10. Al Nasr IS
    Trop Biomed, 2020 Mar 01;37(1):15-23.
    PMID: 33612714
    The organisms of the genus Leishmania are flagellated protozoan parasites and are the causative agents of leishmaniasis. This disease is a major health problem, especially in tropical countries. Currently, cutaneous leishmaniasis is treated by chemotherapy using pentavalent antimonials, but these drugs have serious organo-toxicity, drug resistance on several occasions, and low efficiency in controlling the infection. The present work is carried out to evaluate the in vitro antileishmanial activity of methanolic extracts and phytochemical fractions of two plants ethnobotanically used against leishmaniasis and skin infection, Calotropis procera and Rhazya stricta leaves against Leishmania major promastigote and amastigote stages and cytotoxicity against the Vero cell line. The leaves of C. procera and R. stricta were extracted with methanol and fractionated by petroleum ether, chloroform, ethyl acetate, n-butanol, and water. The methanolic extracts of the leaves of C. procera and R. stricta exhibited antileishmanial activity against L. major promastigotes with IC50 values of 66.8 and 42.4 µg mL-1, respectively. While their CC50 2.3 and 298 µg mL-1 and their SI 0.03 and 7.03 respectively. However, the fractionations of the methanolic extract of C. procera leaves revealed antiparasitic activity against both L. major promastigote and amastigote stages in vitro, which significantly increased with polarity with the exception of n-butanol. Hence the best activity was revealed by the water fraction (IC50 of 26.3 and 29.0 µg mL-1) for the two stages. In conclusion, further phytochemical investigation should be performed for the C. procera water extract in terms of antileishmanial active ingredient isolation that may enhance the possibility of avoiding toxic substances and overcome the low SI (1.1 and 1.01).
    Matched MeSH terms: Leishmania major/drug effects*
  11. Lasing T, Phumee A, Siriyasatien P, Chitchak K, Vanalabhpatana P, Mak KK, et al.
    Bioorg Med Chem, 2020 01 01;28(1):115187.
    PMID: 31761725 DOI: 10.1016/j.bmc.2019.115187
    In a search for potent antileishmanial drug candidates, eighteen rhodacyanine analogues bearing fluorine or perfluoroalkyl substituents at various positions were synthesized. These compounds were tested for their inhibitory activities against Leishmania martiniquensis and L. orientalis. This 'fluorine-walk' analysis revealed that the introduction of fluorine atom at C-5, 6, 5', or 6' on the benzothiazole units led to significant enhancement of the activity, correlating with the less negative reduction potentials of the fluorinated analogues confirmed by the electrochemical study. On the other hand, CF3 and OCF3 groups were found to have detrimental effects, which agreed with the poor aqueous solubility predicted by the in silico ADMET analysis. In addition, some of the analogues including the difluorinated species showed exceptional potency against the promastigote and axenic amastigote stages (IC50 = 40-85 nM), with the activities surpassing both amphotericin B and miltefosine.
    Matched MeSH terms: Leishmania/drug effects*
  12. Taha M, Uddin I, Gollapalli M, Almandil NB, Rahim F, Farooq RK, et al.
    BMC Chem, 2019 Dec;13(1):102.
    PMID: 31410413 DOI: 10.1186/s13065-019-0617-4
    We have synthesized new series of bisindole analogs (1-27), characterized by 1HNMR and HR-EI-MS and evaluated for their anti-leishmanial potential. All compounds showed outstanding inhibitory potential with IC50 values ranging from 0.7 ± 0.01 to 13.30 ± 0.50 µM respectively when compared with standard pentamidine with IC50 value of 7.20 ± 0.20 µM. All analogs showed greater potential than standard except 10, 19 and 23 when compared with standard. Structure activity relationship has been also established for all compounds. Molecular docking studies were carried out to understand the binding interaction of active molecules.
    Matched MeSH terms: Leishmania
  13. Abdelhaleem AA, Elamin EM, Bakheit SM, Mukhtar MM
    Trop Biomed, 2019 Dec 01;36(4):866-873.
    PMID: 33597459
    This study was aimed to identify and characterize Leishmania amastigote, and axenic form antigens. Two in vitro techniques were used to change leishmania parasite isolates from promastigote form to amastigotes and amastigote like (axenic) forms. The main strategy relied upon in vitro infection of murine macrophages cell line J774 with leishmania promastigote, at 37°C with 5% CO2, while the second technique relied upon the culture of promastigote at 37°C with low pH (5.5), and 5-10% CO2. Proteins were extracted and fractionated utilizing 12% Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (SDS PAGE). Antigens were recognized using both immune dot blot and western blot procedures. PCR was performed for recognition of leishmania parasites in infected J774 macrophages. L. major was quicker in infectivity of macrophages cell line than L. donovani. Shared proteins ranging from 26-116 kDa were identified by SDS PAGE in all stages. Immune Dot-blot method showed positive outcomes, while western blot identified an exceptional antigen band of 16 kDa in amastigote, this unique band could be of value in diagnosis and vaccination of leishmaniasis. PCR results confirmed presence of both isolates demonstrating that coinfection is conceivable, and no indications of hereditary recombination at kinetoplast DNA (kDNA) were identified in macrophages simultaneously infected by L. major and L. donovani.
    Matched MeSH terms: Leishmania/immunology; Leishmania/isolation & purification*; Leishmania donovani; Leishmania major
  14. Zin NNINM, Rahimi WNAWM, Bakar NA
    Malays J Med Sci, 2019 Nov;26(6):19-34.
    PMID: 31908584 MyJurnal DOI: 10.21315/mjms2019.26.6.3
    Parasitic diseases represent one of the causes for significant global economic, environmental and public health impacts. The efficacy of currently available anti-parasitic drugs has been threatened by the emergence of single drug- or multidrug-resistant parasite populations, vector threats and high cost of drug development. Therefore, the discovery of more potent anti-parasitic drugs coming from medicinal plants such as Quercus infectoria is seen as a major approach to tackle the problem. A systematic review was conducted to assess the efficacy of Q. infectoria in treating parasitic diseases both in vitro and in vivo due to the lack of such reviews on the anti-parasitic activities of this plant. This review consisted of intensive searches from three databases including PubMed, Science Direct and Scopus. Articles were selected throughout the years, limited to English language and fully documented. A total of 454 potential articles were identified, but only four articles were accepted to be evaluated based on inclusion and exclusion criteria. Although there were insufficient pieces of evidence to account for the efficacy of Q. infectoria against the parasites, this plant appears to have anti-leishmanial, anti-blastocystis and anti-amoebic activities. More studies in vitro and in vivo are warranted to further validate the anti-parasitic efficacy of Q. infectoria.
    Matched MeSH terms: Leishmania
  15. Majid Shah S, Ullah F, Ayaz M, Sadiq A, Hussain S, Ali Shah AU, et al.
    Steroids, 2019 08;148:56-62.
    PMID: 31085212 DOI: 10.1016/j.steroids.2019.05.001
    The current study was aimed to evaluate the anti-leishmanial potentials of β-sitosterol isolated from Ifloga spicata. The anti-leishmanial potential of β-sitosterol is well documented against Leishmania donovani and Leishmania amazonensis but unexplored against Leishmania tropica. Structure of the compound was elucidated by FT-IR, mass spectrometry and multinuclear (1H and 13C) magnetic resonance spectroscopy. The compound was evaluated for its anti-leishmanial potentials against L. tropica KWH23 using in vitro anti-promastigote, DNA interaction, apoptosis, docking studies against leishmanolysin (GP63) and trypanothione reductase (TR) receptors using MOE 2016 software. β-sitosterol exhibited significant activity against leishmania promastigotes with IC50 values of 9.2 ± 0.06 μg/mL. The standard drug glucantaime showed IC50 of 5.33 ± 0.07 µg/mL. Further mechanistic studies including DNA targeting and apoptosis induction via acridine orange assay exhibited promising anti-leishmanial potentials for β-sitosterol. Molecular docking with leishmanolysin (GP63) and trypanothione reductase (TR) receptors displayed the binding scores of β-sitosterol with targets TR and GP63 were -7.659 and -6.966 respectively. The low binding energies -61.54 (for TR) and -33.24 (for GP63) indicate that it strongly bind to the active sites of target receptors. The results confirmed that β-sitosterol have considerable anti-leishmanial potentials and need further studies as potential natural anti-leishmanial agent against L. tropica.
    Matched MeSH terms: Leishmania tropica/drug effects*
  16. Lai JY, Klatt S, Lim TS
    Crit Rev Biotechnol, 2019 May;39(3):380-394.
    PMID: 30720351 DOI: 10.1080/07388551.2019.1566206
    Through the discovery of monoclonal antibody (mAb) technology, profound successes in medical treatment against a wide range of diseases have been achieved. This has led antibodies to emerge as a new class of biodrugs. As the "rising star" in the pharmaceutical market, extensive research and development in antibody production has been carried out in various expression systems including bacteria, insects, plants, yeasts, and mammalian cell lines. The major benefit of eukaryotic expression systems is the ability to carry out posttranslational modifications of the antibody. Glycosylation of therapeutic antibodies is one of these important modifications, due to its influence on antibody structure, stability, serum half-life, and complement recruitment. In recent years, the protozoan parasite Leishmania tarentolae has been introduced as a new eukaryotic expression system. L. tarentolae is rich in glycoproteins with oligosaccharide structures that are very similar to humans. Therefore, it is touted as a potential alternative to mammalian expression systems for therapeutic antibody production. Here, we present a comparative review on the features of the L. tarentolae expression system with other expression platforms such as bacteria, insect cells, yeasts, transgenic plants, and mammalian cells with a focus on mAb production.
    Matched MeSH terms: Leishmania/genetics*; Leishmania/immunology
  17. Almandil NB, Taha M, Rahim F, Wadood A, Imran S, Alqahtani MA, et al.
    Bioorg Chem, 2019 04;85:109-116.
    PMID: 30605884 DOI: 10.1016/j.bioorg.2018.12.025
    New series of quinoline-based thiadiazole analogs (1-20) were synthesized, characterized by EI-MS, 1H NMR and 13C NMR. All synthesized compounds were subjected to their antileishmanial potential. Sixteen analogs 1-10, 12, 13, 16, 17, 18 and 19 with IC50 values in the range of 0.04 ± 0.01 to 5.60 ± 0.21 µM showed tremendously potent inhibition as compared to the standard pentamidine with IC50 value 7.02 ± 0.09 µM. Analogs 11, 14, 15 and 20 with IC50 8.20 ± 0.35, 9.20 ± 0.40, 7.20 ± 0.20 and 9.60 ± 0.40 µM respectively showed good inhibition when compared with the standard. Structure-activity relationships have been also established for all compounds. Molecular docking studies were performed to determine the binding interaction of the compounds with the active site target.
    Matched MeSH terms: Leishmania donovani/chemistry; Leishmania major/drug effects
  18. Khan AH, Noordin R
    Biotechnol Prog, 2019 03;35(2):e2752.
    PMID: 30457225 DOI: 10.1002/btpr.2752
    Homogeneously glycosylated proteins are essential for analyzing the structure of N-glycans, studying their consequences inside cells, and developing therapeutic glycoproteins. However, the isolation of glycoproteins with homogeneous glycans from human is difficult since glycoforms slightly differ from each other with respect to molecular weight and charge. Microbial expression systems have numerous benefits in expression technology and have gained great attention, because they are more adaptable to the biotechnology industry. While selecting an expression host, the glycosylation pattern must be taken into account, because glycosylation strongly depends on cellular production system and selected production clone. This review discussed the technological developments in glycoengineering of microbial expression systems for humanizing the glycosylation profile and highlighted the expression potential of Leishmania expression system. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2752, 2019.
    Matched MeSH terms: Leishmania/metabolism*
  19. Nor Azman NS, Hossan MS, Nissapatorn V, Uthaipibull C, Prommana P, Jin KT, et al.
    Exp Parasitol, 2018 Nov;194:67-78.
    PMID: 30268422 DOI: 10.1016/j.exppara.2018.09.020
    Treatment of drug resistant protozoa, bacteria, and viruses requires new drugs with alternative chemotypes. Such compounds could be found from Southeast Asian medicinal plants. The present study examines the cytotoxic, antileishmanial, and antiplasmodial effects of 11 ethnopharmacologically important plant species in Malaysia. Chloroform extracts were tested for their toxicity against MRC-5 cells and Leishmania donovani by MTT, and chloroquine-resistant Plasmodium falciparum K1 strain by Histidine-Rich Protein II ELISA assays. None of the extract tested was cytotoxic to MRC-5 cells. Extracts of Uvaria grandiflora, Chilocarpus costatus, Tabernaemontana peduncularis, and Leuconotis eugenifolius had good activities against L. donovani with IC50 
    Matched MeSH terms: Leishmania donovani/drug effects*
  20. Fischer K, Diederich S, Smith G, Reiche S, Pinho Dos Reis V, Stroh E, et al.
    PLoS One, 2018;13(4):e0194385.
    PMID: 29708971 DOI: 10.1371/journal.pone.0194385
    Hendra virus (HeV) and Nipah virus (NiV) belong to the genus Henipavirus in the family Paramyxoviridae. Henipavirus infections were first reported in the 1990's causing severe and often fatal outbreaks in domestic animals and humans in Southeast Asia and Australia. NiV infections were observed in humans in Bangladesh, India and in the first outbreak in Malaysia, where pigs were also infected. HeV infections occurred in horses in the North-Eastern regions of Australia, with singular transmission events to humans. Bats of the genus Pteropus have been identified as the reservoir hosts for henipaviruses. Molecular and serological indications for the presence of henipa-like viruses in African fruit bats, pigs and humans have been published recently. In our study, truncated forms of HeV and NiV attachment (G) proteins as well as the full-length NiV nucleocapsid (N) protein were expressed using different expression systems. Based on these recombinant proteins, Enzyme-linked Immunosorbent Assays (ELISA) were developed for the detection of HeV or NiV specific antibodies in porcine serum samples. We used the NiV N ELISA for initial serum screening considering the general reactivity against henipaviruses. The G protein based ELISAs enabled the differentiation between HeV and NiV infections, since as expected, the sera displayed higher reactivity with the respective homologous antigens. In the future, these assays will present valuable tools for serosurveillance of swine and possibly other livestock or wildlife species in affected areas. Such studies will help assessing the potential risk for human and animal health worldwide by elucidating the distribution of henipaviruses.
    Matched MeSH terms: Leishmania/metabolism
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