Introduction: Carboxypeptidase, a member of the metallopeptidase M32 family, catalyses the C-terminal hydrolysis of a variety of peptides and proteins in the presence of metal ions.
Objective: To characterize Leishmania donovani carboxypeptidase (LdCP) in miltefosine (MIL) drug-resistant parasites.
Methods: We performed the MTT assay and cell cycle analysis to confirm the MIL resistance of clinical isolates.
() promastigotes secrete exosomes that are crucial in host-pathogen interactions and intercellular communication by carrying parasite-specific molecules. Although the composition of cargos in exosomes is known, the effects of the unique metabolic repertoire on immunometabolism rewiring of macrophage polarization are poorly understood. Interestingly, we found the enrichment of polyamines (PAs) such as spermidine and putrescine in the -exosomes.
View Article and Find Full Text PDFVisceral leishmaniasis (VL) is referred to as the most severe and fatal type of leishmaniasis basically caused by and . The most effective method for preventing the spread of the disease is vaccination. Till today, there is no promising licensed vaccination for human VL.
View Article and Find Full Text PDFCandida albicans, a polymorphic opportunistic pathogen of humans, can exist in different morphological forms like yeast, hyphae, pseudohyphae, chlamydospores, and white and opaque cells. Proteomic analysis of opaque form of C. albicans ATCC 10231 is carried out in the present study using microflow liquid chromatography-tandem mass spectrometry and validated using expression analysis of selected genes using reverse transcription quantitative real-time PCR and mitochondrial membrane potential assay.
View Article and Find Full Text PDFAAPS PharmSciTech
January 2023
The utility of andrographolide (AN) in visceral leishmaniasis (VL) and cutaneous leishmaniasis (CL) is limited owing to poor solubility, hindered permeation, and unstable structure under physiological conditions. The present study mainly focuses on synthesizing of andrographolide-Soya-L-α-phosphatidyl choline (ANSPC) complex in ethanol and its characterization using various spectral and analytical techniques. Results from FT-IR, H NMR, ROSEY, and in silico docking techniques suggest ANSPC complex formation due to inter-molecular interaction between the hydrophilic head of SPC and hydroxyl group of AN present at 24th position.
View Article and Find Full Text PDFVisceral leishmaniasis (VL) is the deadliest form of leishmaniasis without a safer treatment option. This study implies drug repurposing to find a novel antileishmanial compound, namely febrifugine dihydrochloride (FFG) targeting Leishmania antioxidant system. Starting with virtual screening revealed the high binding affinity and lead likeness of FFG against the trypanothione reductase (TR) enzyme of Leishmania donovani, followed by experimental validation.
View Article and Find Full Text PDFObesity is one of the foremost risk factors in coronavirus infection resulting in severe illness and mortality as the pandemic progresses. Obesity is a well-known predisposed chronic inflammatory condition. The dynamics of obesity and its impacts on immunity may change the disease severity of pneumonia, especially in acute respiratory distress syndrome, a primary cause of death from SARS-CoV-2 infection.
View Article and Find Full Text PDFResistance to antileishmanial drugs such as sodium stibogluconate (SSG), amphotericin B (Amp-B), and miltefosine is on the rise, and alternate strategies for effective treatment have gained importance in recent years. Although nanoparticle (NP)-based composite drugs that have emerged recently have been found to be effective, the associated toxicity limits their usage. Bimetallic NPs produced through reduction with medicinal plant extracts are proposed to overcome the toxicity of the NPs.
View Article and Find Full Text PDFThe emergence of drug-resistant Leishmania is the major challenge to management of visceral leishmaniasis (VL) in areas in which this parasite is endemic. Miltefosine has been widely used against VL, but the emergence of resistant strains could impose a significant threat in the near future. The present study used high-throughput proteomics to determine whether proteins are differentially expressed in miltefosine-resistant (BHU875) and -sensitive (DD8) Leishmania donovani strains.
View Article and Find Full Text PDFLeptin, a pleiotropic protein has long been recognized to play an important role in the regulation of energy homeostasis, metabolism, neuroendocrine function, and other physiological functions through its effects on the central nervous system (CNS) and peripheral tissues. Leptin is secreted by adipose tissue and encoded by the obese () gene. Leptin acts as a central mediator which regulates immunity as well as nutrition.
View Article and Find Full Text PDFObjective: Present in silico study was carried out to explore the mode of inhibition of Leishmania donovani dihydrofolate reductase-thymidylate synthase (Ld DHFR-TS) enzyme by Withaferin-A, a withanolide isolated from Withania somnifera. Withaferin-A (WA) is known for its profound multifaceted properties, but its antileishmanial activity is not well understood. The parasite's DHFR-TS enzyme is diverse from its mammalian host and could be a potential drug target in parasites.
View Article and Find Full Text PDFApoptosis is a physiological cell death process essential for development, tissue homeostasis, and for immune defense of multicellular animals. Inhibitors of apoptosis proteins (IAPs) regulate apoptosis in response to various cellular assaults. Using both genetic and pharmacological approaches we demonstrate here that the IAPs not only support opportunistic survival of intracellular human pathogens like but also control plasticity of iNOS+ M1 macrophage during the course of infection and render them refractory for immune stimulation.
View Article and Find Full Text PDFVisceral leishmaniasis (VL) is responsible for several deaths in malnourished children accompanied by diminished circulating leptin and impaired cell-mediated immunity. Typically, leptin deficiency is associated with the Th2 polarization that markedly coincides with the pathogenesis of VL. The aim of the present study was to unravel the prophylactic role of leptin in malnutrition-coupled VL mice.
View Article and Find Full Text PDFVisceral leishmaniasis (VL) causes fatal life-threatening disease, if left untreated. The current drugs have various limitations; hence, natural products from medicinal plants are being focused in search of new drugs to treat leishmaniasis. The aim of the present study was to evaluate the antileishmanial and immunomodulatory activities of F5 and F6 alcoholic fractions from leaves and purified withaferin-A in -infected peritoneal macrophages and BALB/c mice.
View Article and Find Full Text PDFABSTACT Artemisia nilagirica (Clarke) is a widely used medicinal herb in Indian traditional system of medicine. Therefore, the present study was designed to evaluate the effects of A. nilagirica extracts/fractions on inhibition of proliferation and apoptosis in a human monocytic leukemia (THP-1) cell line.
View Article and Find Full Text PDFVisceral leishmaniasis (VL) is caused by the protozoan parasite Leishmania donovani There are no vaccines and available drugs against leishmaniasis are toxic. Immunomodulators that specifically boost the anti-microbial activities of the immune cells could alleviate several of these limitations. Therefore, finding novel immunomodulators for VL therapy is a pressing need.
View Article and Find Full Text PDFVisceral leishmaniasis (VL) is an infectious disease responsible for several deaths in malnourished children due to impaired cell-mediated immunity, which is accompanied by low circulating leptin levels. The cytokine function of leptin is implicated for several immune regulation activities such as hematopoiesis, angiogenesis, innate and adaptive immunity. Its deficiency associated with polarization of Th2 response, which coincides with VL pathogenesis.
View Article and Find Full Text PDFWithaferin A is an abundant withanolide present in Withania somnifera leaves and to some extent in roots. It has been known for its profound anti-cancer properties, but its role in counteracting the Leishmania donovani infection has to be explored. Pteridine reductase 1 (PTR1) is involved in pteridine salvage and an important enzyme for the parasite growth, which could be targeted for the development of an efficient antileishmanial drug.
View Article and Find Full Text PDFThe toxicity and emergence of resistance to available chemical drugs against visceral leishmaniasis is evoking to explore herbal treatment. One such attempt with the Neem is being reported here. The current study is primarily focused to evaluate the anti-leishmanial effects of Neem leaf extracts.
View Article and Find Full Text PDFThe aim of this study was to isolate and evaluate the withanolides in inducing apoptotic like death in Leishmania donovani in vitro. Withanolides were fractionated and isolated from the leaves of Withania somnifera and LC-MS/MS analysis of two fractions namely, F5 and F6 of ethanolic extracts, obtained through column chromatography with silica gel, was performed. The antileishmanial effect of withanolides on L.
View Article and Find Full Text PDFIn this study we describe a rapid and novel method to assess the morphological stage differentiation in Leishmania donovani by flow cytometry (FCM). FCM is fast, accurate, and inexpensive to study the stage differentiation of promastigote into L. donovani axenic amastigote (LdAxAm).
View Article and Find Full Text PDFThe mechanisms underlying the failure to contain the growth of Leishmania parasites in human visceral leishmaniasis (VL) are not understood. L donovani amastigotes were quantified in cultured splenic aspirate cells to assess the function of IL-10 in lesional tissue ex vivo. In 67 patients with active VL, IL-10 neutralization promoted parasite killing in 73% and complete clearance in 30%, while 18% had more parasites and 9% did not change.
View Article and Find Full Text PDFSerial dilution of blood and spleen biopsy specimens, plated on Novy-MacNeal-Nicolle (NNN) blood agar using microtiter culture plates, is a sensitive and reproducible method for detection and growth of Leishmania parasites. Plates could be easily monitored, and growth could be rapidly detected. Moreover, parasite number may be estimated using this technique.
View Article and Find Full Text PDFVisceral leishmaniasis (VL) is a life-threatening disease characterized by uncontrolled parasitization of the spleen, liver, and bone marrow. Interleukin (IL)-10 has been implicated in the suppression of host immunity in human VL based on the elevated levels of IL-10 observed in plasma and lesional tissue, and its role in preventing clearance of Leishmania donovani in murine models of VL. The aim of this study was to identify the cellular source of IL-10 in human VL and determine if CD4(+)CD25(+) (Foxp3(high)) regulatory T (T reg) cells are associated with active disease.
View Article and Find Full Text PDFUsed with blood or serum, a new anti-K39 antibody immunochromatographic strip test (IT-Leish; DiaMed AG) proved sensitive (range, 99 to 100%) and specific (range, 95 to 100%) for the noninvasive serodiagnosis of visceral leishmaniasis in India. Used with serum, the IT-Leish test and the existing Kalazar Detect test (InBios International, Inc.) yielded comparable results for symptomatic infection and identified apparent subclinical infection in 15 to 32% of healthy residents in a region where visceral leishmaniasis is highly endemic.
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