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1.
Heliyon ; 10(14): e34073, 2024 Jul 30.
Article in English | MEDLINE | ID: mdl-39092244

ABSTRACT

Cancer and diabetes represent significant challenges in the field of biomedicine, with major and global impacts on public health. Acacia nilotica, commonly called 'gum arabic tree,' is recognized for its unique biomedical properties. The current study aimed to investigate the pharmacological potential of A. nilotica-based zinc-oxide nanoparticles (ZnO-NPs) in comparison to the ethanol and methanol-based extracts against cancer, diabetes, and oxidative stress. Green synthesis of ZnO-NPs was performed using barks of Acacia nilotica. Different techniques for the characterization of ZnO-NPs, including UV-Visible spectroscopy, Scanning Electron Microscopy, Fourier Transmission Infrared (FT-IR) spectroscopy, and X-ray Diffraction (XRD), were utilized. The morphological analysis of ZnO-NPs revealed that the fine NPs have mean particle sizes of 15 ± 1.5 nm. For the solvent based-extraction, leaves and barks were utilized and dissolved into ethanol and methanol for further processing. The MTT assay revealed that the optimum concentration of ZnO-NPs to inhibit the proliferation of liver cancer cell line HepG2 was 100 µg/mL where 67.0 % inhibition was observed; and both ethanol- and methanol-based extracts showed optimum inhibition at 100 µg/mL. The DPPH assay further demonstrated that 250 µg/mL of ZnO-NPs and 1000 µg/mL of both ethanol- and methanol-based extracts, as the optimum concentration for antioxidant activity (with 73.1 %, 68.9 % and 68.2 % inhibition respectively). The α-Glucosidase inhibition assay revealed that 250 µg/mL of ZnO-NPs and 10 µg/mL of both ethanol- and methanol-based extracts as the optimum concentration for antidiabetic activity (with 95 %, 93.7 % and 93.4 % inhibition respectively). The study provided interesting insights into the efficacy and reliability of ZnO-NPs for potential pharmacological application. Further research should be focused on examining specific pathways and the safety of ZnO-NPs in comparison to solvent-based extracts.

2.
Food Chem ; 458: 140184, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38968708

ABSTRACT

The public health concern of antibiotic residues in animal-origin food has been a long-standing issue. In this work, we present a novel method for antibiotic detection, leveraging optical weak value amplification and harnessing an indirect competitive inhibition assay, which significantly boosts the system's sensitivity in identifying small molecule antibiotics. We chose chloramphenicol as a model compound and mixed it with chloramphenicol-bovine serum albumin conjugates to bind to the chloramphenicol antibody competitively. We achieved a broad linear detection range of up to 3.24 ng/mL and a high concentration resolution of 33.20 pg/mL. To further validate the universality of our proposed detection methodology, we successfully applied it to testing gibberellin and tetracycline. Moreover, we conducted regeneration experiments and real-sample correlation studies. This study introduces a novel strategy for the label-free optical sensing of small molecule antibiotics, greatly expanding the range of applications for sensors utilizing optical weak value amplification.

3.
Biochim Biophys Acta Biomembr ; : 184367, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38969202

ABSTRACT

The natural product curcumin and some of its analogs are known inhibitors of the transmembrane enzyme sarco/endoplasmic reticulum calcium ATPase (SERCA). Despite their widespread use, the curcuminoids' binding site in SERCA and their relevant interactions with the enzyme remain elusive. This lack of knowledge has prevented the development of curcuminoids into valuable experimental tools or into agents of therapeutic value. We used the crystal structures of SERCA in its E1 conformation in conjunction with computational tools such as docking and surface screens to determine the most likely curcumin binding site, along with key enzyme/inhibitor interactions. Additionally, we determined the inhibitory potencies and binding affinities for a small set of curcumin analogs. The predicted curcumin binding site is a narrow cleft in the transmembrane section of SERCA, close to the transmembrane/cytosol interface. In addition to pronounced complementarity in shape and hydrophobicity profiles between curcumin and the binding pocket, several hydrogen bonds were observed that were spread over the entire curcumin scaffold, involving residues on several transmembrane helices. Docking-predicted interactions were compatible with experimental observations for inhibitory potencies and binding affinities. Based on these findings, we propose an inhibition mechanism that assumes that the presence of a curcuminoid in the binding site arrests the catalytic cycle of SERCA by preventing it from converting from the E1 to the E2 conformation. This blockage of conformational change is accomplished by a combination of steric hinderance and hydrogen-bond-based cross-linking of transmembrane helices that require flexibility throughout the catalytic cycle.

4.
Microorganisms ; 12(6)2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38930523

ABSTRACT

Babesia duncani (B. duncani), a protozoan parasite prevalent in North America, is a significant threat for human health. Given the regulatory role of pyruvate kinase I (PyK I) in glycolytic metabolism flux and ATP generation, PyK I has been considered the target for drug intervention for a long time. In this study, B. duncani PyK I (BdPyK I) was successfully cloned, expressed, and purified. Polyclonal antibodies were confirmed to recognize the native BdPyK I protein (56 kDa) using Western blotting. AlphaFold software predicted the three-dimensional structure of BdPyK I, and molecular docking with small molecules was conducted to identify potential binding sites of inhibitor on BdPyK I. Moreover, inhibitory effects of six inhibitors (tannic acid, apigenin, shikonin, PKM2 inhibitor, rosiglitazone, and pioglitazone) on BdPyK I were examined under the optimal enzymatic conditions of 3 mM PEP and 3 mM ADP, and significant activity reduction was found. Enzyme kinetics and growth inhibition assays further confirmed the reliability of these inhibitors, with PKM2 inhibitor, tannic acid, and apigenin exhibiting the highest selectivity index as specific inhibitors for B. duncani. Subsequently, key amino acid residues were mutated in both BdPyK I and Homo sapiens pyruvate kinase I (HPyK I), and two differential amino acid residues (isoleucine and phenylalanine) were identified between HPyK I and BdPyK I through PyK activity detection experiments. These findings lay foundation for understanding the role of PyK I in the growth and development of B. duncani, providing insights for babesiosis prevention and drug development.

5.
Article in English | MEDLINE | ID: mdl-38857317

ABSTRACT

Zearalenone (ZEN), a nonsteroidal estrogenic mycotoxin, causes enormous economic losses in the food and feed industries. Simple, rapid, low-cost, and quantitative analysis of ZEN is particularly urgent in the fields of food safety and animal husbandry. Using the bioluminescent bacterium Photobacterium phosphoreum T3, we propose a bioluminescence inhibition assay to evaluate ZEN levels quickly. The limit of detection (LOD), limit of quantification (LOQ), and quantitative working range of this bioluminescence inhibition assay were 0.1 µg/mL, 5 µg/mL, and 5-100 µg/mL, respectively. The concentration-response curve of the bioluminescence inhibition rate and ZEN concentration was plotted within the range 5 to 100 µg/mL, as follows: y = 0.0069x2 - 0.0190x + 7.9907 (R2 = 0.9943, y is luminescence inhibition rate, x is ZEN concentration). First, we used the bioluminescence inhibition assay to detect the remaining ZEN in samples treated with purified lactonohydrolase ZHD101. The bioluminescence inhibition assay results showed a strong correlation with the HPLC analysis. Furthermore, we successfully evaluated the overall toxicity of samples treated with purified peroxidase Prx and H2O2 using the P. phosphoreum T3 bioluminescence inhibition assay. The results indicate that the degradation products of ZEN created by purified peroxidase Prx and H2O2 showed little toxicity to P. phosphoreum T3. In this study, a simple, rapid, and low-cost assay method of zearalenone by bioluminescent P. phosphoreum T3 was developed. The bioluminescence inhibition assay could be used to estimate the efficiency of enzymatic degradation of ZEN.


Subject(s)
Photobacterium , Zearalenone , Zearalenone/analysis , Zearalenone/metabolism , Photobacterium/drug effects , Luminescent Measurements , Luminescence , Food Contamination/analysis
6.
Heliyon ; 10(10): e30715, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38774337

ABSTRACT

Ascorbic acid plays a significant role in regulation of various bodily functions with high concentrations in immune cells and being involved in connective tissue maintenance. Commonly it is detected through various colorimetric methods. In this study, we propose a one-step simple method based on the inhibitory activity of ascorbic acid on horseradish peroxidase and hydrogen peroxide. The detection is observed by colorimetric changes to TMB (3,3',5,5' tetramethylbenzidine). The enzyme inhibition unit was optimized with a high level of linearity (r2 = 0.9999) and the level of detection and level of quantification were found to be 1.35 nM and 4.08 nM, respectively with higher sensitive compared to the HPLC method (11 µM). Both intra and inter-assays showed high correlations at different AA concentrations. (r2 > 0.9999). Similar results were also observed for vitamin C tablets, ascorbate salts, fruits, and market products (r2 = 0.999). There was negligible effect of interference by citric acid, lactic acid, tartaric acids, and glucose with high recoveries (>98%) at 1 mg/mL to 0.0078 mg/mL concentration ranges. The recovery error (RE%) was found to be less than 10%. Our detection method is distinguished by its simplicity, nano-level of detection, reproducibility, and potential application and adaptability as a point-of-use test.

7.
Front Cell Infect Microbiol ; 14: 1396786, 2024.
Article in English | MEDLINE | ID: mdl-38746786

ABSTRACT

Antimalarial resistance to the first-line partner drug piperaquine (PPQ) threatens the effectiveness of artemisinin-based combination therapy. In vitro piperaquine resistance is characterized by incomplete growth inhibition, i.e. increased parasite growth at higher drug concentrations. However, the 50% inhibitory concentrations (IC50) remain relatively stable across parasite lines. Measuring parasite viability of a drug-resistant Cambodian Plasmodium falciparum isolate in a parasite reduction ratio (PRR) assay helped to better understand the resistance phenotype towards PPQ. In this parasite isolate, incomplete growth inhibition translated to only a 2.5-fold increase in IC50 but a dramatic decrease of parasite killing in the PRR assay. Hence, this pilot study reveals the potential of in vitro parasite viability assays as an important, additional tool when it comes to guiding decision-making in preclinical drug development and post approval. To the best of our knowledge, this is the first time that a compound was tested against a drug-resistant parasite in the in vitro PRR assay.


Subject(s)
Antimalarials , Drug Resistance , Inhibitory Concentration 50 , Malaria, Falciparum , Plasmodium falciparum , Quinolines , Plasmodium falciparum/drug effects , Plasmodium falciparum/growth & development , Quinolines/pharmacology , Antimalarials/pharmacology , Humans , Malaria, Falciparum/drug therapy , Malaria, Falciparum/parasitology , Parasitic Sensitivity Tests , Pilot Projects , Artemisinins/pharmacology
8.
Foods ; 13(10)2024 May 07.
Article in English | MEDLINE | ID: mdl-38790740

ABSTRACT

Despite the rapid and dynamic evolution of research into dietary polyphenols, there is still a knowledge gap regarding their bioaccessibility since it could be influenced by the chemical and nutritional compositions of the food matrix. This study aimed to describe the impact of food thickeners (xanthan gum, guar gum, ß-glucan, pectin) on the bioactivity of flavonoids from saffron floral by-products in model beverages before and after thermal processing. The different beverage formulas were characterized in terms of polyphenolic composition using HPLC-DAD-ESI-MSn and rheological properties. The impact of food thickeners and thermal processing on the inhibition of digestive enzymes was also determined. The model beverages mainly presented glycosylated flavonols (of kaempferol, quercetin, and isorhamnetin), with a reduced content in some heat-treated samples. The inhibitory effect on α-amylase was only detected in heat-treated beverages, showing the formulation without any thickener to have the greatest inhibitory effect. Finally, the presence of saffron floral by-products in the beverages showed a tendency to decrease the flow consistency index (K) and an increase in the flow behavior index (n), most probably driven by the aggregation of phenolics with thickeners. Therefore, this research provides new insights into the development of flavonoid-rich beverages in order to ensure that they exert the expected beneficial effects after their ingestion.

9.
Vaccine ; 42(16): 3621-3629, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38704253

ABSTRACT

Recent data indicate increasing disease burden and importance of Plasmodium vivax (Pv) malaria. A robust assay will be essential for blood-stage Pv vaccine development. Results of the in vitro growth inhibition assay (GIA) with transgenic P. knowlesi (Pk) parasites expressing the Pv Duffy-binding protein region II (PvDBPII) correlate with in vivo protection in the first PvDBPII controlled human malaria infection (CHMI) trials, making the PkGIA an ideal selection tool once the precision of the assay is defined. To determine the precision in percentage of inhibition in GIA (%GIA) and in GIA50 (antibody concentration that gave 50 %GIA), ten GIAs with transgenic Pk parasites were conducted with four different anti-PvDBPII human monoclonal antibodies (mAbs) at concentrations of 0.016 to 2 mg/mL, and three GIAs with eighty anti-PvDBPII human polyclonal antibodies (pAbs) at 10 mg/mL. A significant assay-to-assay variation was observed, and the analysis revealed a standard deviation (SD) of 13.1 in the mAb and 5.94 in the pAb dataset for %GIA, with a LogGIA50 SD of 0.299 (for mAbs). Moreover, the ninety-five percent confidence interval (95 %CI) for %GIA or GIA50 in repeat assays was calculated in this investigation. The error range determined in this study will help researchers to compare PkGIA results from different assays and studies appropriately, thus supporting the development of future blood-stage malaria vaccine candidates, specifically second-generation PvDBPII-based formulations.


Subject(s)
Antibodies, Protozoan , Antigens, Protozoan , Malaria Vaccines , Plasmodium knowlesi , Plasmodium vivax , Protozoan Proteins , Receptors, Cell Surface , Malaria Vaccines/immunology , Plasmodium knowlesi/immunology , Plasmodium knowlesi/genetics , Protozoan Proteins/immunology , Protozoan Proteins/genetics , Plasmodium vivax/immunology , Antigens, Protozoan/immunology , Antigens, Protozoan/genetics , Humans , Receptors, Cell Surface/immunology , Receptors, Cell Surface/genetics , Antibodies, Protozoan/immunology , Antibodies, Protozoan/blood , Malaria, Vivax/prevention & control , Malaria, Vivax/immunology , Antibodies, Monoclonal/immunology , Vaccine Development/methods , Animals
10.
Heliyon ; 10(8): e29433, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38644870

ABSTRACT

Nanoparticles have different shapes and sizes between the range of 1-100 nm, which show advantages for stabilizing compounds, higher carrier capacity, and lower costs. Metal nanoparticles such as copper, gold, silver, and zinc are favorable components for various applications due to their interesting properties. In the present study, nanoparticles were synthesized by reduction with flower extracts of Bauhinia variegate & Saussurea lappa that were used to stabilize the copper nanoparticles. Furthermore, the characterization of plants synthesized copper nanoparticles was carried out through UV-visible dynamic light scattering. Additionally, morphological characterization of nanoparticles was confirmed by scanning electron microscopy and energy dispersive X-ray spectroscopy confirmed the elemental composition of copper nanoparticles. Powder X-ray diffraction was conducted for the analysis of crystallinity, purity, and crystal size of plant-synthesized copper nanoparticles. The average particle size was evaluated and exhibited the particle size at the peak of 8.721 nm and 98.03 nm for flower extracts of Bauhinia variegate & Saussurea lappa copper nanoparticles. The Fourier Transform Infrared spectrum was taken to scrutinize the various functional groups that were responsible for the reduction of the copper ions. The antimicrobial results against the bacterial strains with the positive test results of the zone of inhibition were for Bauhinia variegate (17 mm, 18 mm, 19 mm, and 18 mm) and Saussurea lappa (17 mm, 19 mm, 18 mm, and 18 mm) respectively for plants synthesized copper nanoparticles against the Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia and Pseudomonas aeruginosa. Lipase inhibition assay and Amylase inhibition assay with different concentrations (20 µg/mL to 100 µg/mL) for Bauhinia variegate & Saussurea lappa (12.34 %-59.67 % and 10.50 %-47.01 %) and (34.52 %-89.02 % and 22.34 %-56.45 %) confirmed the anti-obesity and anti-diabetic activities of plants extract synthesized copper nanoparticles.

11.
Heliyon ; 10(8): e29460, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38665554

ABSTRACT

This research aimed to enhance dermal delivery and optimize depigmentation therapy by designing mesoporous silica nanoparticles (MSNs) encapsulating azelaic acid (AZA) within a gel matrix. The MSNs were prepared using the sol-gel method. After subsequent processes, including acid extraction and drug loading, were then elucidated through PDI, size, zeta-potential, entrapment efficiency, nitrogen adsorption assay, FE-SEM, thermogravimetric analysis, differential scanning calorimetry, Fourier transform infrared spectroscopy, X-ray diffraction, and tyrosinase inhibition assay, were employed to assess the formulation. In-vitro stability tests for both AZA-MSN gel (AZCG) and AZA-loaded mesoporous silica gel (AZMG) were conducted at 8 °C, 25 °C, 40 °C, and 40 °C + 75 % RH, encompassing assessments of color, liquefaction, pH, and conductivity. Our findings showed a notable entrapment efficiency of 93.46 % for AZA-MSNs, with FE-SEM illustrating porous spherical MSNs. The particle size of AZA-MSNs was determined to be 211.9 nm, with a pore size of 2.47 nm and XRD analysis confirmed the amorphous state of AZA within the MSN carriers. Rheology examination indicated a non-Newtonian flow, while ex-vivo rat skin permeation studies conducted in a phosphate buffer (pH = 5.5) demonstrated a biphasic release pattern with 85.53 % cumulative drug permeation for AZA-MSNs. Overall, the study endorse the potential of AZA-MSNs as an efficacious and stable formulation for AZA delivery, highlighting their promise in addressing pigmentation concerns compared to conventional approaches.

12.
Int J Biol Macromol ; 267(Pt 1): 131326, 2024 May.
Article in English | MEDLINE | ID: mdl-38569988

ABSTRACT

Aspartate kinase (AK), an enzyme from the Wolbachia endosymbiont of Brugia malayi (WBm), plays a pivotal role in the bacterial cell wall and amino acid biosynthesis, rendering it an attractive candidate for therapeutic intervention. Allosteric inhibition of aspartate kinase is a prevalent mode of regulation across microorganisms and plants, often modulated by end products such as lysine, threonine, methionine, or meso-diaminopimelate. The intricate and diverse nature of microbial allosteric regulation underscores the need for rigorous investigation. This study employs a combined experimental and computational approach to decipher the allosteric regulation of WBmAK. Molecular Dynamics (MD) simulations elucidate that ATP (cofactor) and ASP (substrate) binding induce a closed conformation, promoting enzymatic activity. In contrast, the binding of lysine (allosteric inhibitor) leads to enzyme inactivation and an open conformation. The enzymatic assay demonstrates the optimal activity of WBmAK at 28 °C and a pH of 8.0. Notably, the allosteric inhibition study highlights lysine as a more potent inhibitor compared to threonine. Importantly, this investigation sheds light on the allosteric mechanism governing WBmAK and imparts novel insights into structure-based drug discovery, paving the way for the development of effective inhibitors against filarial pathogens.


Subject(s)
Aspartate Kinase , Brugia malayi , Molecular Dynamics Simulation , Wolbachia , Brugia malayi/enzymology , Brugia malayi/microbiology , Allosteric Regulation , Animals , Aspartate Kinase/metabolism , Aspartate Kinase/genetics , Aspartate Kinase/chemistry , Symbiosis , Adenosine Triphosphate/metabolism , Lysine/chemistry , Lysine/metabolism
13.
Curr Med Chem ; 2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38591207

ABSTRACT

BACKGROUND/AIM: The global pandemic caused by the novel SARS-CoV-2 virus underscores the urgent need for therapeutic interventions. Targeting the virus's main protease (Mpro), crucial for viral replication, is a promising strategy. OBJECTIVE: The current study aims to discover novel inhibitors of Mpro. METHODS: The current study identified five natural compounds (myrrhanol B (C1), myrrhanone B (C2), catechin (C3), quercetin (C4), and feralolide (C5) with strong inhibitory potential against Mpro through virtual screening and computational methods, predicting their binding efficiencies and validated it using the in-vitro inhibition activity. The selected compound's toxicity was examined using the MTT assay on a human BJ cell line. RESULTS: Compound C1 exhibited the highest binding affinity, with a docking score of -9.82 kcal/mol and strong hydrogen bond interactions within Mpro's active site. A microscale molecular dynamics simulation confirmed the stability and tight fit of the compounds in the protein's active pocket, showing superior binding interactions. in vitro assays validated their inhibitory effects, with C1 having the most significant potency (IC50 = 2.85 µM). The non-toxic nature of these compounds in human BJ cell lines was also confirmed, advocating their safety profile. CONCLUSION: These findings highlight the effectiveness of combining computational and experimental approaches to identify potential lead compounds for SARS-CoV-2, with C1-C5 emerging as promising candidates for further drug development against this virus.

14.
Pathogens ; 13(3)2024 Feb 29.
Article in English | MEDLINE | ID: mdl-38535560

ABSTRACT

It is controversial how useful bioassays are for identifying the in vivo toxicity of hazardous environmental exposures. In this study, fruiting bodies of forest mushrooms (n = 46), indoor mold colonies (n = 412), fungal secondary metabolites (n = 18), xenobiotic chemicals such as biocides and detergents (n = 6), and methanol extracts of indoor dusts from urban buildings (n = 26) were screened with two different bioactivity assays: boar sperm motility inhibition (BSMI) and inhibition of cell proliferation (ICP) tests. For the forest mushrooms, the toxicity testing result was positive for 100% of poisonous-classified species, 69% of non-edible-classified species, and 18% of edible-classified species. Colonies of 21 isolates of Ascomycota mold fungal species previously isolated from water-damaged buildings proved to be toxic in the tests. Out of the fungal metabolites and xenobiotic chemicals, 94% and 100% were toxic, respectively. Out of the indoor dusts from moldy-classified houses (n = 12) and from dry, mold-free houses (n = 14), 50% and 57% were toxic, respectively. The bioassay tests, however, could not differentiate the samples from indoor dusts of moldy-classified buildings from those from the mold-free buildings. Xenobiotic chemicals and indoor dusts were more toxic in the BSMI assay than in the ICP assay, whereas the opposite results were obtained with the Ascomycota mold colonies and fungal secondary metabolites. The tests recognized unknown methanol-soluble thermoresistant substances in indoor settled dusts. Toxic indoor dusts may indicate a harmful exposure, regardless of whether the toxicity is due to xenobiotic chemicals or microbial metabolites.

15.
Front Immunol ; 15: 1355983, 2024.
Article in English | MEDLINE | ID: mdl-38380319

ABSTRACT

Introduction: First described by Wallis et al. in 2001 for the assessment of TB drugs, the direct mycobacterial growth inhibition assay (MGIA) offers a tractable ex vivo tool measuring the combined influences of host immunity, strain virulence and intervention effects. Over the past 13 years, we have led efforts to adapt the direct MGIA for the assessment of TB vaccines including optimisation, harmonisation and validation of BCG vaccine-induced responses as a benchmark, as well as assay transfer to institutes worldwide. Methods: We have performed a systematic review on the primary published literature describing the development and applications of the direct MGIA from 2001 to June 2023 in accordance with the PRISMA reporting guidelines. Results: We describe 63 studies in which the direct MGIA has been applied across species for the evaluation of TB drugs and novel TB vaccine candidates, the study of clinical cohorts including those with comorbidities, and to further understanding of potential immune correlates of protection from TB. We provide a comprehensive update on progress of the assay since its conception and critically evaluate current findings and evidence supporting its utility, highlighting priorities for future directions. Discussion: While further standardisation and validation work is required, significant advancements have been made in the past two decades. The direct MGIA provides a potentially valuable tool for the early evaluation of TB drug and vaccine candidates, clinical cohorts, and immune mechanisms of mycobacterial control. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42023423491.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis , Humans , BCG Vaccine , Tuberculosis/microbiology , Tuberculosis Vaccines
16.
Tuberculosis (Edinb) ; 146: 102494, 2024 May.
Article in English | MEDLINE | ID: mdl-38367368

ABSTRACT

Human tuberculosis (TB) is caused by various members of the Mycobacterium tuberculosis (Mtb) complex. Differences in host response to infection have been reported, illustrative of a need to evaluate efficacy of novel vaccine candidates against multiple strains in preclinical studies. We previously showed that the murine lung and spleen direct mycobacterial growth inhibition assay (MGIA) can be used to assess control of ex vivo mycobacterial growth by host cells. The number of mice required for the assay is significantly lower than in vivo studies, facilitating testing of multiple strains and/or the incorporation of other cellular analyses. Here, we provide proof-of-concept that the murine MGIA can be applied to evaluate vaccine-induced protection against multiple Mtb clinical isolates. Using an ancient and modern strain of the Mtb complex, we demonstrate that ex vivo bacillus Calmette-Guérin (BCG)-mediated mycobacterial growth inhibition recapitulates protection observed in the lung and spleen following in vivo infection of mice. Further, we provide the first report of cellular and transcriptional correlates of BCG-induced growth inhibition in the lung MGIA. The ex vivo MGIA represents a promising platform to gain early insight into vaccine performance against a collection of Mtb strains and improve preclinical evaluation of TB vaccine candidates.


Subject(s)
Mycobacterium bovis , Mycobacterium tuberculosis , Tuberculosis Vaccines , Tuberculosis , Mice , Humans , Animals , BCG Vaccine , High-Throughput Screening Assays , Tuberculosis/microbiology
17.
Pathogens ; 13(2)2024 Feb 11.
Article in English | MEDLINE | ID: mdl-38392900

ABSTRACT

Influenza D virus (IDV) is a novel orthomyxovirus initially isolated from pigs exhibiting influenza-like disease in the USA. Since then, IDV has been detected worldwide in several host species, including livestock animals, whilst specific antibodies have been identified in humans, raising concerns about interspecies transmission and zoonotic risks. Few data regarding the seroprevalence of IDV in small ruminants have been available to date. In this study, we assessed the prevalence of antibodies against IDV in ovine serum samples in Sicily, Southern Italy. Six hundred serum samples, collected from dairy sheep herds located in Sicily in 2022, were tested by haemagglutination inhibition (HI) and virus neutralization (VN) assays using reference strains, D/660 and D/OK, representative of two distinct IDV lineages circulating in Italy. Out of 600 tested samples, 168 (28.0%) tested positive to either IDV strain D/660 or D/OK or to both by HI whilst 378 (63.0%) tested positive to either IDV strain D/660 or D/OK or to both by VN. Overall, our findings demonstrate that IDV circulates in ovine dairy herds in Sicily. Since IDV seems to have a broad host range and it has zoonotic potential, it is important to collect epidemiological information on susceptible species.

18.
Int J Immunopathol Pharmacol ; 38: 3946320231223004, 2024.
Article in English | MEDLINE | ID: mdl-38217433

ABSTRACT

The symptoms of celery allergy are mainly presented as oral allergy symptom, but there are several case reports of patients who experienced anaphylaxis. Defensin (Api g 7), as a novel allergen in celery root, was described in 2022 r. The female patient had a history of several episodes of dyspnea and cough, associated with ingestion of spice mixes containing dried celery. Up to the point of hospitalization, there were no objective tests, either sIgE or skin prick tests, that would confirm celery sensitization. During hospitalization, patient had a positive double-blind placebo-controlled food challenge with cooked celery. The patient was sensitized to mugwort defensin Art v 1. An inhibition assay with celery allergen extract was performed to prove cross-sensitization between Art v 1 and celery allergen responsible for symptoms in the patient. In conclusion, Api g 7 is an important celery allergen that can be responsible for severe reactions. Its cross-reactivity with Art v 1 is characteristic. Negative diagnostic tests with celery do not exclude Api g 7 sensitization.


Subject(s)
Anaphylaxis , Food Hypersensitivity , Humans , Female , Anaphylaxis/diagnosis , Food Hypersensitivity/diagnosis , Pollen , Plant Proteins/adverse effects , Allergens , Defensins , Skin Tests/adverse effects
19.
Int J Biol Macromol ; 259(Pt 2): 129314, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38211912

ABSTRACT

Protein kinases have emerged as major contributors to various diseases. They are currently exploited as a potential target in drug discovery because they play crucial roles in cell signaling, growth, and regulation. Their dysregulation is associated with inflammatory disorders, cancer, and neurodegenerative diseases. Pyruvate dehydrogenase kinase 3 (PDK3) has become an attractive drug target in cancer therapeutics. In the present study, we investigated the effective role of thymol in PDK3 inhibition due to the high affinity predicted through molecular docking studies. Hence, to better understand this inhibition mechanism, we carried out a 100 ns molecular dynamics (MD) simulation to analyse the dynamics and stability of the PDK3-thymol complex. The PDK3-thymol complex was stable and energetically favourable, with many intramolecular hydrogen bond interactions in the PDK3-thymol complex. Enzyme inhibition assay showed significant inhibition of PDK3 by thymol, revealing potential inhibitory action of thymol towards PDK3 (IC50 = 2.66 µM). In summary, we established thymol as one of the potential inhibitors of PDK3, proposing promising therapeutic implications for severe diseases associated with PDK3 dysregulation. This study further advances our understanding of thymol's therapeutic capabilities and potential role in cancer treatment.


Subject(s)
Neoplasms , Thymol , Humans , Pyruvate Dehydrogenase Acetyl-Transferring Kinase/chemistry , Thymol/pharmacology , Molecular Docking Simulation , Protein Kinases/metabolism , Neoplasms/drug therapy
20.
Micromachines (Basel) ; 14(12)2023 Dec 08.
Article in English | MEDLINE | ID: mdl-38138386

ABSTRACT

The present work is a review of the research on using hydrogels based on natural biodegradable polymers, starch, and gelatin for enzyme immobilization. This review addresses the main properties of starch and gelatin that make them promising materials in biotechnology for producing enzyme preparations stable during use and storage and insensitive to chemical and physical impacts. The authors summarize their achievements in developing the preparations of enzymes immobilized in starch and gelatin gels and assess their activity, stability, and sensitivity for use as biorecognition elements of enzyme inhibition-based biosensors.

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