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Biology subjects

Manzoor, S.

Publications and source records attributed to Manzoor, S..

11 recordsLinked to original sources

Green Synthesized Zinc Oxide Nanoparticles from Azadirachta indica Exhibit Enhanced Antibacterial, Antioxidant and Cytotoxic Activities

Green synthesis of zinc oxide nanoparticles (ZnO NPs) offers a sustainable strategy for developing multifunctional antimicrobial nanomaterials. In this study, ZnO NPs were synthesized using Azadirachta indica leaf extract and characterized by UV-vis spectroscopy, FTIR, XRD, SEM, and GC-MS. The nanoparticles exhibited a characteristic absorption peak at 352 nm, a direct band gap of 3.07 eV, and hexagonal wurtzite crystallinity with an average crystallite size of approximately 32 nm. The biosynthesized ZnO NPs showed concentration-dependent antibacterial activity against Erwinia carotovora, producing inhibition zones of up to 25.9 mm. Mechanistic studies revealed significant membrane damage, evidenced by 4.77-fold and 5.62-fold increases in extracellular protein and amino acid leakage, respectively, with marked alterations in bacterial protein profiles detected by SDS-PAGE. The nanoparticles also exhibited strong antioxidant activity, achieving 89.4% DPPH radical scavenging, and induced dose-dependent cytotoxicity in HepG2 cells with an estimated IC50 of 124.8 g/mL. These findings demonstrate that neem mediated ZnO nanoparticles possess potent antibacterial activity through membrane disruption while exhibiting promising antioxidant properties, highlighting their potential as eco-friendly nanomaterials for the management of bacterial soft rot and other phytopathogenic diseases.

microbiology↗

In Vivo 4D Oxy-Wavelet MRI as a Non-Invasive Biomarker of Brain Mitochondrial Function across the Lifespan

Mitochondria are essential for cellular energy production and are particularly critical for brain development and function. Neurons rely predominantly on oxidative phosphorylation for energy production, rendering the brain highly vulnerable to mitochondrial dysfunction. Consequently, impaired mitochondrial function contributes to a broad spectrum of neurological and systemic disorders, making mitochondria attractive therapeutic targets. Despite this importance, there is currently no non-invasive, spatially resolved method to assess mitochondrial function in the intact living brain. Here, we establish a non-invasive functional MRI approach--4D Oxy-wavelet MRI--to probe in vivo mitochondrial electron transport chain (ETC) function in a spatially specific manner across the lifespan, from fetal to adult brains. This method employs a low-rank k-t sub-Nyquist acquisition strategy to achieve simultaneous structural and functional imaging with high spatial (78 m) and temporal ([~]14 ms) resolution, enabling motion-robust imaging in multi-fetal mouse pregnancies. Mitochondrial ETC function is interrogated by measuring oxygen homeostasis responses to brief hypoxic challenges, analyzed using computational time-frequency wavelet profiling. We validate this approach in mouse models of mitochondrial respiratory chain disease and late-onset Alzheimers disease, from in utero fetuses to adults, and demonstrate reproducibility and specificity using pharmacological hyperemia and ETC complex I inhibition. We further show parallel wavelet responses in placenta and fetal brain, enabling multi-organ interrogation of the placenta-brain axis. Finally, we present first-in-human feasibility data, supporting translational potential for non-invasive assessment of mitochondrial function in living brains across the lifespan.

bioengineering↗

A host ATPase essential for rhinovirus replication is an antiviral target with a high barrier to resistance

Rhinoviruses are the leading cause of acute respiratory illnesses and comprise more than 170 types that constantly circulate in humans worldwide. Beyond common colds, rhinoviruses can trigger severe symptoms, particularly in young children, older adults and people with asthma or chronic obstructive pulmonary disease. Despite their clinical and socio-economic impact, no approved vaccine or antiviral treatment exist. Here, we uncovered the interaction of the host AAA+ ATPase RUVBL1/2 with rhinovirus non-structural protein 2C and we demonstrated that RUVBL1/2 is strictly and specifically required for the replication of the viral RNA of the most prevalent and pathogenic rhinovirus species. Pharmacological inhibition of RUVBL1/2 ATPase activity efficiently inhibited rhinovirus replication in a human nasal epithelium model, even post-infection. Moreover, serial viral passaging in the presence of a RUVBL1/2 inhibitor did not lead to the emergence of resistance. These findings reveal an unexpected and strong host dependency with promising potential for antiviral targeting.

microbiology↗

NUAK2 is a therapeutically tractable regulator of RNA splicing and tumor progression in neuroendocrine prostate cancer

Prostate cancer remains a leading cause of cancer-related mortality in men, with aggressive, treatment-emergent androgen receptor (AR)-indifferent subtypes, including double-negative prostate cancer (DNPC) and neuroendocrine prostate cancer (NEPC), posing major clinical challenges due to limited therapeutic options. NUAK family kinase 2 (NUAK2), an AMPK-related kinase, has been implicated in tumor growth and metastatic progression; however, its functional significance and therapeutic potential in advanced prostate cancer remain largely unexplored. Here, we identify NUAK2 as a therapeutically actionable kinase dependency in AR-indifferent prostate cancer. Transcriptomic analyses across independent patient cohorts demonstrated progressive upregulation of NUAK2 with disease progression, with the highest expression in NEPC. Immunohistochemical analysis of clinical specimens further confirmed elevated NUAK2 protein expression in NEPC relative to prostate adenocarcinoma. Genetic loss- and gain-of-function studies established NUAK2 as a functional dependency that promotes tumor cell proliferation, clonogenic growth, and tumor growth in vivo. Mechanistically, integrated proteomic analyses revealed that NUAK2 associates with spliceosomal and RNA-processing machinery, while NUAK2 perturbation induced widespread alterations in pre-mRNA splicing programs involving genes linked to mitotic regulation and oncogenic signaling. Pharmacologic studies identified trilaciclib (G1T-28), a clinically approved CDK4/6 inhibitor, as a functionally relevant NUAK2 inhibitor that directly engages NUAK2, suppresses tumor growth, and enhances the efficacy of platinum-based chemotherapy across multiple preclinical models. Collectively, these findings uncover NUAK2 as a previously unrecognized regulator of RNA splicing and therapeutic vulnerability in AR-indifferent prostate cancer and provide a rationale for repurposing G1T-28 and developing NUAK2-directed therapeutic strategies for aggressive, treatment-refractory prostate cancer.

cancer biology↗

Identification of novel therapeutic inhibitors against E6 and E7 oncogenes of HPV-16 associated with cervical cancer

BackgroundHuman Papilloma Virus type 16 (HPV-16) is highly oncogenic with the E6 and E7 oncogenes playing crucial roles in the pathogenesis of HPV-related cervical carcinogenesis. Targeting these oncoproteins with specific inhibitors offers a promising approach for therapeutic intervention. ObjectiveThis study aimed to identify potential inhibitors of the HPV-16 E6 and E7 oncoproteins through an in silico approach, providing a foundation for the development of targeted therapies against HPV associated malignancies. MethodologyWe performed virtual screening on a library of 1000 compounds to identify promising candidates. Subsequent molecular docking studies were conducted to assess the binding affinities of the promising candidates. The top-scoring compounds for oncoproteins were then subjected to molecular dynamics simulations to evaluate their stability and interaction profiles. ResultsThe virtual screening identified 14 promising candidates followed by docking studies. Among these Galangin was identified as a promising inhibitor for the E6 oncogene, while Neoechinulin showed potential as an inhibitor of the E7 oncogene. ConclusionOur findings suggest Galangin and Neoechinulin with high potential as therapeutic inhibitors of HPV-16 E6 and E7 oncogenes respectively. These inhibitors could contribute significantly to the development of targeted therapies against HPV associated malignancies. However, further in vitro and in vivo investigations are required to use these phytochemicals as antiviral agents against HPV-16.

cancer biology↗

Mitigation of Fetal Irradiation Injury from Mid-Gestation Total Body Radiation with Mitochondrial-Targeted GS-Nitroxide JP4-039

Victims of a radiation terrorist event will include pregnant women and unborn fetuses. Mitochondrial dysfunction and oxidative stress are key pathogenic factors of fetal irradiation injury. The goal of this preclinical study is to investigate the efficacy of mitigating fetal irradiation injury by maternal administration of the mitochondrial-targeted gramicidin S (GS)- nitroxide radiation mitigator, JP4-039. Pregnant female C57BL/6NTac mice received 3 Gy total body ionizing irradiation (TBI) at mid-gestation embryonic day 13.5 (E13.5). Using novel time- and-motion-resolved 4D in utero magnetic resonance imaging (4D-uMRI), we found TBI caused extensive injury to the fetal brain that included cerebral hemorrhage, loss of cerebral tissue, and hydrocephalus with excessive accumulation of cerebrospinal fluid (CSF). Histopathology of the fetal mouse brain showed broken cerebral vessels and elevated apoptosis. Further use of novel 4D Oxy-wavelet MRI capable of probing in vivo mitochondrial function in intact brain revealed significant reduction of mitochondrial function in the fetal brain after 3Gy TBI. This was validated by ex vivo Oroboros mitochondrial respirometry. Maternal administration JP4-039 one day after TBI (E14.5), which can pass through the placental barrier, significantly reduced fetal brain radiation injury and improved fetal brain mitochondrial respiration. This also preserved cerebral brain tissue integrity and reduced cerebral hemorrhage and cell death. As JP4-039 administration did not change litter sizes or fetus viability, together these findings indicate JP4-039 can be deployed as a safe and effective mitigator of fetal radiation injury from mid-gestational in utero ionizing radiation exposure. One Sentence SummaryMitochondrial-targeted gramicidin S (GS)-nitroxide JP4-039 is safe and effective radiation mitigator for mid-gestational fetal irradiation injury.

developmental biology↗

The Host-specific Microbiota is Required for Diet-Specific Metabolic Homeostasis

In complex mammals, the importance and host-specificity of microbial communities have been demonstrated through their positive effects on host immune fitness or performance. However, whether host metabolic physiology homeostasis depends on a specific bacterial community exclusive to the host remains unclear. Here, we show that the coevolved host-specific microbiota is required to maintain diet-specific flexible and sufficient metabolic homeostasis through a high colonization rate, modulating gut metabolites, and related targets. Using germ-free (GF) mice, we tested whether the fitness benefiting the host metabolic phenotype of microbiota was host-specific. We demonstrated that GF mice associated with exogenous microbiota (human microbiota (HM)), which exhibited different and reduced gut microbial species diversity, significantly elevated metabolic rate, and exhibited metabolic insufficiency, all characteristics of GF mice. Strikingly, the absence of the host-specific microbiome attenuated high-fat diet-specific metabolism features. Different diets caused different metabolic changes in only host-specific microbiota-associated mice, not the host-microbiota mismatched mice. While RNA sequencing revealed subtle changes in the expression of genes in the liver, GF mice and HM mice showed considerably altered expression of genes associated with metabolic physiology compared to GF mice associated with host-specific microbiota. The effect of diet outweighed microbiota in the liver transcriptome. These changes occurred in the setting of decreased luminal short-chain fatty acids (SCFAs) and the secondary bile acid (BAs) pool and downstream gut signaling targets in HM and GF mice, which affects whole-body metabolism. These data indicate that a foreign microbial community provides little metabolic benefit to the host when compared to a host-specific microbiome, due to the colonization selection pressure and microbiota-derived metabolites dysfunction. Overall, microbiome fitness effects on the host metabolic phenotype were host-specific. Understanding the impact of the host-specificity of the microbiome on metabolic homeostasis may provide important insights for building a better probiotic. HighlightsO_LIMicrobiome fitness effects on the host metabolic phenotype were host-specific in mammals. C_LIO_LIHuman microbiota-associated mice exhibited lower host metabolic fitness or performance, and similar functional costs in GF mice. C_LIO_LIDifferent diets cause different metabolic changes only in host-specific microbiota-associated mice, not the host-microbiota mismatched mice. C_LIO_LIThe defective gut microbiota in host-specific microbiota, microbial metabolites and related targets likely drive the metabolic homeostasis. C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=132 SRC="FIGDIR/small/565654v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@16a864org.highwire.dtl.DTLVardef@1894996org.highwire.dtl.DTLVardef@3e5429org.highwire.dtl.DTLVardef@77bfb_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

Gut Microbes and the Liver Circadian Clock Partition Glucose and Lipid Metabolism

Circadian rhythms govern glucose homeostasis, and their dysregulation leads to complex metabolic diseases. Gut microbes also exhibit diurnal rhythms that influence host circadian networks and metabolic processes, yet underlying mechanisms remain elusive. Here, we show hierarchical, bi-directional communication between the liver circadian clock, gut microbes, and glucose homeostasis in mice. The liver clock, but not the forebrain clock, requires gut microbes to drive glucose clearance and gluconeogenesis. Liver clock dysfunctionality expands proportions and abundances of oscillating microbial features by two-fold relative to controls. The liver clock is the primary driver of differential and rhythmic hepatic expression of glucose and fatty acid metabolic pathways. Absent the liver clock, gut microbes provide secondary cues that dampen these rhythms, resulting in reduced utilization of lipids as fuel relative to carbohydrates. Together, the liver clock transduces signals from gut microbes necessary to regulate glucose and lipid metabolism and meet energy demands over 24 hours. HighlightsThe liver circadian clock is autonomous from the central clock in metabolic regulation Liver clock and gut microbes interact to direct hepatic glucose and lipid metabolism Reciprocating host-microbe interactions drive rhythmic hepatic transcription Perturbed liver Bmal1 results in chaotic downstream oscillators and metabolism

physiology↗

An Endogenously activated antiviral state restricts SARS-CoV-2 infection in differentiated primary airway epithelial cells

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of the coronavirus disease-19 (COVID-19) pandemic, was identified in late 2019 and went on to cause over 3.3 million deaths in 15 months. To date, targeted antiviral interventions against COVID-19 are limited. The spectrum of SARS-CoV-2 infection ranges from asymptomatic to fatal disease. However, the reasons for varying outcomes to SARS-CoV-2 infection are yet to be elucidated. Here we show that an endogenously activated interferon lambda (IFN{lambda}) pathway leads to resistance against SARS-CoV-2 infection. Using a well-differentiated primary nasal epithelial cell (WD-PNEC) model from multiple adult donors, we discovered that susceptibility to SARS-CoV-2 infection, but not respiratory syncytial virus (RSV) infection, varied. One of four donors was resistant to SARS-CoV-2 infection. High baseline IFN{lambda} expression levels and associated interferon stimulated genes correlated with resistance to SARS-CoV-2 infection. Inhibition of the JAK/STAT pathway in WD-PNECs with high endogenous IFN{lambda} secretion resulted in higher SARS-CoV-2 titres. Conversely, prophylactic IFN{lambda} treatment of WD-PNECs susceptible to infection resulted in reduced viral titres. An endogenously activated IFN{lambda} response, possibly due to genetic differences, may be one explanation for the differences in susceptibility to SARS-CoV-2 infection in humans. Importantly, our work supports the continued exploration of IFN{lambda} as a potential pharmaceutical against SARS-CoV-2 infection.

immunology↗

Interrupting reactivation of immunological memory reprograms allergy and averts anaphylaxis

IgE production against innocuous antigens can lead to life-threatening reactions such as anaphylaxis. While IgE levels drastically decline with strict allergen avoidance, the ability to regenerate IgE can persist for a lifetime, as is the case for peanut allergy. The mechanism by which IgE regenerates remains unresolved. A novel culture system and application of single-cell RNA-sequencing, elucidated the transcriptomic signature of human peanut-reactive B and T cells and revealed IL-4/IL-13 as a signaling pathway critical for the IgE recall response. Indeed, interruption of this pathway not only prevented IgE production and anaphylaxis, but also reprogrammed the pathogenic response against peanut. This investigation advances our understanding of the mechanism that regenerates IgE in food allergy and spotlights IL-4/IL-13 blockade as a therapeutic with disease-transforming potential. One Sentence SummarySingle-cell transcriptomics of allergic memory responses reveals how to teach the immune system to forget.

immunology↗

Comparative primary paediatric nasal epithelial cell culture differentiation and RSV-induced cytopathogenesis following culture in two commercial media.

The culture of differentiated human airway epithelial cells allows the study of pathogen-host interactions and innate immune responses in a physiologically relevant in vitro model. As the use of primary cell culture has gained popularity the availability of the reagents needed to generate these cultures has increased. In this study we assessed two different media, Promocell and PneumaCult, during the differentiation and maintenance of well-differentiated primary nasal epithelial cell cultures (WD-PNECs). We compared and contrasted the consequences of these media on WD-PNEC morphological and physiological characteristics and their responses to respiratory syncytial virus (RSV) infection. We found that cultures generated using PneumaCult resulted in greater total numbers of smaller, tightly packed, pseudostratified cells. However, cultures from both media resulted in similar proportions of ciliated and goblet cells. There were no differences in RSV growth kinetics, although more ciliated cells were infected in the PneumaCult cultures. There was also significantly more IL-29/IFN{lambda}1 secreted from PneumaCult compared to Promocell cultures. In conclusion, the type of medium used for the differentiation of primary human airway epithelial cells impacts experimental results.

cell biology↗