Biochemical and Biophysical Research Communications
○ Elsevier BV
Preprints posted in the last 30 days, ranked by how well they match Biochemical and Biophysical Research Communications's content profile, based on 78 papers previously published here. The average preprint has a 0.06% match score for this journal, so anything above that is already an above-average fit.
Limerick, A.; Chu, C. Y.; Turner, J. S.; Brautigan, D. L.; Xu, W.; Fu, Z.
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BackgroundKATNIP (Katanin-interacting protein), also known as KIAA0556, is one of the human genes with pathogenic variants linked to Joubert syndrome, an archetypal neurodevelopmental ciliopathy. KATNIP is a scaffolding protein with a critical role in ciliogenesis. In this study, we characterized the ciliopathy phenotypes due to KATNIP gene deletion. ResultsWe produced a Katnip null mouse model using CRISPR-Cas12a (Cpf1). The null heterozygotes appeared normal while the homozygotes died around postnatal day 9, showing severe hydrocephalus and deficiency in neuroprogenitor cell proliferation. Katnip-deficient cells in the brain have a higher rate of cilia formation and longer cilia than wild type cells. ConclusionKATNIP loss of function gives rise to hydrocephalus found in Joubert syndrome. The results indicate that KATNIP restricts ciliogenesis and cilia extension and supports proliferation of neuroprogenitor cells in the brain.
Shivakumar, A.; Hunt, A. G.; Chakrabarti, M.
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Hemp (Cannabis sativa) produces a wide array of medicinally significant compounds, including cannabidiol (CBD). These compounds are predominantly synthesized in female hemp inflorescences. The proposed research utilizes next-generation sequencing-based transcriptome analysis using a 3{square}-end-directed approach to identify differentially expressed genes between male and female hemp plants at the early vegetative stage. 886 differentially expressed genes (DEGs) were identified, a majority of which were upregulated in males compared to females. We hypothesized that alternative RNA processing contributes to sex-specific gene expression. To this end, 932 genes were identified that exhibited significant changes in poly(A) site usage when comparing males and females. These genes were much more likely to be differentially expressed, supportive of this hypothesis. Males tend to have longer 3 UTRs with canonical motifs found in the Near-Upstream Elements (NUE), compared to the shorter 3 UTRs in females, which have A-rich motifs near the cleavage site. This suggests that polyadenylation remodels hemp mRNAs with distal poly(A) sites being preferred in males. To further investigate when this sex-specific gene expression program is established, RNA was isolated from plants at various developmental stages, such as developing seeds, four-day-old seedlings, and different developmental stages up to four weeks after sowing. Diagnostic male-specific genes were analyzed using RT/PCR. The results indicate that sex-specific gene expression is not evident in seeds but rather is set during or after germination. SignificanceO_LIHemp males tend to have longer 3 UTRs with canonical motifs found in the Near-Upstream Elements (NUE), compared to the shorter 3 UTRs in females, which have A-rich motifs near the cleavage site. C_LIO_LIThe sex-specific gene expression program is not yet established in mature seed but is set in the time between germination and 4 days of growth. C_LI
Bueno, C.; Martinez-Morga, M.; Rodriguez-Lozano, F. J.; Garcia-Bernal, D.; Martinez, S.; Moraleda, J. M.; Blanquer, M.
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BackgroundDirect conversion of human somatic cells into functional neurons could offer a faster way to generate patient-specific neurons for use in regenerative medicine, disease modelling, and drug development. Although it has been reported that neuronal direct reprogramming bypasses the intermediate pluripotent state, no reports have included time-lapse experiments, potentially overlooking transient intermediate states. Recent studies have shown that the conversion of human mesenchymal stromal cells (hMSCs) into neuron-like cells involves a transition through a transient intermediate state. Therefore, further research is needed to fully understand the process by which human somatic cells can become neurons without cell division. In this study we investigates whether direct neuronal reprogramming of human bone marrow-derived MSC (hBM-MSCs), dental pulp-derived MSC (hDP-MSCs), and adult human dermal fibroblasts (HDFa), involves a transient intermediate state, and sought to further validate the neuronal identity of hMSC-derived induced neurons. MethodsIn this study, we conducted time-lapse experiments to observe the transformation of hBM-MSCs, hDP-MSCs and HDFa, into neurons using a small-molecule-based direct reprogramming protocol. Cellular and ultrastructural changes were further characterized by confocal and electron microscopy. ResultsDirect conversion of hBM-MSCs, hDP-MSCs and HDFa into neuron-like cells occurred rapidly and in absence of cell division. Time-lapse analyses revealed that reprogramming proceeds through a transient intermediate state characterized by distinct morphological changes and dynamic nuclear remodelling. Furthermore, we found that neuron-like cells derived from hBM-MSCs and hDP-MSCs exhibit neuronal polarization, expressed specific neuronal and synaptic markers, formed interconnected cellular networks, and exhibited functional plasticity, providing further evidence that hMSCs can become functional neurons. ConclusionsThis study provides clear evidence that the direct neuronal reprogramming process involves a transition through an intermediate, transient state. Our findings also provide further evidence that hMSCs can become functional neurons. In summary, our work provides new insights into the direct neuronal reprogramming process, which is essential for advancing both developmental biology and regenerative medicine.
Catarina Silva-Almeida, C.; Mee, P. J. J.; Esquiva Diaz, M.; Ali, W.; Ho, S.; Pickup, M.; Webb, S.; Rajesh, D.
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Pluripotent stem cells derived from livestock species represent valuable systems for studying early mammalian development and for establishing renewable, well-defined cell sources; however, direct comparative characterization of distinct pluripotent stem cell platforms in sheep remains limited. In this study, we established and evaluated two ovine pluripotent stem cell types: reprogrammed induced pluripotent stem cells (siPSCs) and embryonic disc-derived stem cells (sEDSCs). Both siPSCs and sEDSCs exhibited core features of pluripotency, including compact colony morphology, alkaline phosphatase activity, expression of key pluripotency-associated markers, and maintenance of a normal ovine karyotype. Flow cytometry and quantitative RT-PCR analyses revealed broadly overlapping yet distinguishable pluripotency marker expression profiles between the two cell types. Functional pluripotency was confirmed by embryoid body formation and in vitro differentiation into derivatives of all three germ layers. To further assess lineage-specific differentiation competence and compare functional outputs relevant to mesodermal differentiation, both pluripotent stem cell types were directed towards the adipogenic lineage. While siPSCs and sEDSCs were each capable of adipogenic differentiation, differences in differentiation efficiency and marker expression were observed. Together, these findings demonstrate that ovine siPSCs and sEDSCs share core pluripotency characteristics while retaining distinct molecular and functional properties, providing a robust comparative framework for studies of ovine pluripotency, lineage specification, and stem cell biology.
Kostareva, O. S.; Eliseeva, I. A.; Buyan, A. I.; Lyabin, D. N.; Tishchenko, S. V.; Mikhaylina, A. O.
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Nucleobindin 1 (NUCB1) is a multifunctional conserved protein located in Golgi luminal, nucleus, extracellular and cytosolic pools. NUCB1 is multidomain protein comprised of a signal peptide, a DNA-binding domain, a leucine zipper and Ca2+ -binding domain. The multiple domains and localization of NUCB1 potentiates its interactions with various partners, such as DNA, Gi3 protein, cyclooxygenase 2, LRP10 and RNA suggests its importance in the regulation of many cellular events. We revealed that NUCB1 contains three RNA-binding regions and able to interact with two RNA fragments. It was suggested possible variants of the participation of NUCB1 in the interaction of the two partially complementary RNAs. The RNA-binding properties of the NUCB1 were also confirmed in vivo experiments.
Eberand, B. M.; Hao, H.; Cielesh, M.; Muthukrishnan, K.; Kambanis, L.; Ayoub, A.; Kong, Y.; Fenwick, J.; Heilbronn, L.; Payne, R. J.; Passam, F. H.; Haltiwanger, R. S.; Larance, M.
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O-fucosylation plays an essential role in controlling protein folding, secretion and protein-protein interactions within the extracellular space. Recently, we identified a new form of protein O-fucosylation occurring on the N-terminal Elastin Microfibril Interaction (EMI) domain of several secreted proteins, mediated by two previously uncharacterized protein O-fucosyltransferases, POFUT3 (FUT10) and POFUT4 (FUT11). As all POFUT enzymes (POFUT1-4) are highly specific for the three-dimensional (3D) structure of their substrate protein domains, we postulated that structural homologues of these domains in other proteins may also be O-fucosylated. Here, we employed iterative protein structural homology searches as a novel strategy for identifying EMI-like domains that may serve as potential substrates for POFUT3/4. We discovered that microfibrillar-associated protein 2 and 5 (MFAP2/MFAP5) contain EMI-like domains and are O-fucosylated at high stoichiometry in human tissues. Unexpectedly, we showed that only POFUT3 is both necessary and sufficient for MFAP2/MFAP5 O-fucosylation, despite POFUT4 also having strong protein-protein interactions with MFAP2/MFAP5. Finally, we determined that O-fucosylation of MFAP2/MFAP5 is required for their efficient secretion, similar to other EMI domain-containing proteins. Together, these data demonstrate the power of sensitive structural homology analysis in identifying new enzyme-substrate relationships and protein-protein interactions.
Gautam, A. K.; umarao, P.; Gourinath, S.
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The Rho family of small GTPases plays a critical role in regulating actin cytoskeleton dynamics during endocytic processes in E. histolytica, including phagocytosis, pinocytosis, and trogocytosis. These proteins act as molecular switches, transitioning between inactive GDP-bound and active GTP-bound states, with guanine nucleotide exchange factors (GEFs) catalyzing this transition. Among the GEFs, EhFP10--a FYVE-domain-containing protein harbouring Dbl homology (DH) and pleckstrin homology (PH) domain was observed in phagocytosis along with seven functionally characterized Rho GTPases (EhRho1, EhRho2, EhRho4, EhRho5, EhRho6, EhRho8, and EhRho13). To study the specificity of FP10, a combination of GEF activity, binding affinity, and molecular dynamics simulations was used to characterize the interactions between EhFP10 and seven Rho GTPases systematically. The results revealed EhRho2 as the most specific and high-affinity interactor of EhFP10, with the highest nucleotide exchange rate and lowest dissociation constant (KD = 0.58 {micro}M). Structural modeling, sequence alignment, and interaction mapping further demonstrated that EhRho2 retains critical contact residues--such as Glu33, Arg4, and Leu69--that are variably absent in other isoforms, correlating with decreased GEF responsiveness. Molecular dynamics simulations and cross-correlation analyses supported the presence of a stable and coordinated interaction interface in the EhFP10-EhRho2 complex, distinguishing it from less active complexes. These findings indicate a highly selective GEF-GTPase module in E. histolytica, analogous to those in higher eukaryotes. The results uncover a potential regulatory mechanism specific to pathogenic amoebae and present EhFP10-EhRho2 as a novel therapeutic target for disrupting cytoskeleton-mediated processes crucial to virulence.
Yu, J.; Li, H.-Z.; Wang, J.-J.; Liu, Y.-L.; Guo, Z.-Y.
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The mucosal chemoattractant C-X-C motif chemokine ligand 17 (CXCL17) was recently identified as a ligand for the orphan G protein-coupled receptor 25 (GPR25). Although CXCL17 orthologs have been identified in fishes, amphibians, and mammals, their presence in reptiles and birds remains unclear. In this study, we employed bioinformatic searches based on gene synteny and sequence features to identify CXCL17 orthologs in public databases. We identified functional CXCL17 orthologs in 46 reptilian species, including lizards, snakes, turtles, and alligators. In contrast, we found only non-functional gene relics in 22 bird species, suggesting the avian lineage lost functional CXCL17 during evolution. A recombinant reptilian CXCL17 from the loggerhead turtle (Caretta caretta), termed Cc-CXCL17, directly bound to and efficiently activated its corresponding receptor, Cc-GPR25, in a C-terminal fragment-dependent manner. Activation of Cc-GPR25 by Cc-CXCL17 also induced chemotactic movement of transfected human embryonic kidney (HEK) 293T cells. In cross-species activity assays, CXCL17s from human and tropical clawed frog could activate Cc-GPR25 albeit with lower potency, but fish orthologs lacked this activity; all tested CXCL17s had no detectable activity towards chicken GPR25, but Cc-CXCL17 had low activity towards mallard GPR25. Our findings demonstrate the presence of functional CXCL17 orthologs in extant reptiles and provide evidence for their evolutionary loss in birds, offering new insights into the phylogenetic distribution of the newly identified CXCL17-GPR25 signaling system.
Fedorova, A. M.; Milentyeva, I. S.; Asyakina, L. K.; Prosekov, A. Y.
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This paper presents the results of a structural analysis of chlorogenic acid isolated from a 70% ethanol extract of red clover (Trifolium pratense) callus culture. X-ray phase analysis showed that the sample was crystalline and single-phase and crystallized in an orthorhombic unit cell with the following parameters: a = 36.7548(5) [A], b = 11.0770(3) [A], c = 7.7947(2) [A], V = 3173.46(11) [A]3, R-Bragg = 0.347 %, Rexp = 4.75 %, Rwp = 5.83 %, Rp = 4.39 %, GOF = 1.23 %. NMR spectroscopy data (1H, 13C{1H}, 2D 1H1H-COSY, 1H13C-HSQC, 1H13C-HMBC) confirmed that the chemical structure and purity of the sample fully corresponded to chlorogenic acid, with no chemical impurities detected. Complete proton and carbon atom assignments are provided.
Shi, W. O.; MacMackin-Ingle, T.; Perez, M. W.; Griffith, W. P.; Chen, L.; Seshu, J.; Renthal, R.
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A proteomic analysis of Ixodes scapularis nymph saliva identified 252 proteins, including six tubular lipid-binding proteins (TULIPs). Comparing nymphs fed on mice that were uninfected or infected with Borrelia burgdorferi, twelve salivary proteins showed significant differences in the amounts detected, including XP_040079658.2, which we refer to as TULIP2. Considering the known immunity-related functions of some TULIPs, we expressed and purified TULIP2 from Escherichia coli and analyzed its interaction with B. burgdorferi lipids. The purification of TULIP2 from E. coli presented many obstacles, due to insolubility, which is consistent with previous reports from studies of other TULIP family members. The binding results showed specificity for B. burgdorferi lipids, with evidence for cholesteryl {beta}-galactoside as a major binding target. Molecular modeling of TULIP2 did not show any strong lipid binding sites. We used molecular dynamics simulation of TULIP2 to explore its conformational landscape by thermal unfolding. The earliest unfolding intermediate opened a hydrophobic pocket to which cholesteryl {beta}-galactoside was predicted to bind strongly. We propose that a specific lipid bilayer interaction with TULIP2 triggers the opening of the ligand-binding site.
Taylor, A. L.; Snyder, N. W.; Bartman, C. R.
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Coenzyme A is an essential cofactor synthesized from pantothenate, cysteine, and ATP, and is involved in numerous processes of cellular metabolism through its ability to carry activated acyl groups. Coenzyme A participates in catabolism of carbohydrate, fat and amino acids; biosynthesis of fatty acids, cholesterol and heme; and protein modification including acetylation and 4-phosphopantetheinylation. Despite CoAs critical functions, the regulation of CoA levels and the rate of CoA synthesis in different cell types and disease states are not well understood. One reason for this gap is that many acyl-CoA species are analytically challenging to measure due to factors including instability, poor ionization, and the wide range of biochemical properties conferred by different acyl chain lengths. In addition, most current methods do not support analysis of CoA isotopic labeling, which is required to quantify CoA synthesis rate or to measure absolute concentration using isotope-labeled internal standards. Here, we describe a method to quantify the concentration and isotopic labeling of total CoA, defined as the sum of CoASH plus all acyl-CoA species. Acyl-CoA species are hydrolyzed using sodium hydroxide to remove acyl chains, then CoA is derivatized on the thiol with N-ethylmaleimide (NEM). Following protein precipitation and solid phase extraction, samples are analyzed by liquid chromatography-mass spectrometry. This method is linear in a wide range that captures mouse tissue CoA levels, with accuracy within 15% error and precision below 15% relative standard deviation for both pure standards and tissue samples. We applied this method to measure total CoA concentration in five tissues from male and female mice, and total CoA synthesis rate in mouse liver via infusion of 13C-15N-pantothenate. Overall, this method offers a tractable approach to measure total CoA concentration and isotopic labeling to enable study of total CoA synthesis rates and concentrations in health and disease.
Anderson, N.; Todd, K.; Casiano, M.; Maheswaran, N.; Blankenberger, A.; Singh, A.; Relich, R. F.; Tilston-Lunel, N. L.; Vornhagen, J.
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Klebsiella pneumoniae (Kp) is a common antibiotic-resistant pathogen that colonizes the gastrointestinal tract and can disseminate to peripheral sites, causing a range of infections including bacteremia, urinary tract infections, and pneumonia. Intestinal colonization with Kp is a risk factor for subsequent infection, as the colonizing strain frequently corresponds to the infecting isolate. Accordingly, targeting Kp prior to dissemination at the site of colonization through decolonization strategies offers a promising approach to mitigate infection risk. In this study, we evaluated the repurposing of existing drugs with previously uncharacterized antibacterial activity as candidates for Kp decolonization. To this end, we screened an antiviral compound library for their activity against Kp. We identified and validated six compounds with previously uncharacterized activity against Kp. Then, we screened a library of clinical Kp strains against a subset of these compounds and found that their activity was strain-specific to degrees that differed based on the compound. Finally, we tested the activity of these compounds in conditions relevant to the human gut. We determined the activity of these candidates was dependent on biological context. Collectively, these findings support further investigation of antiviral drugs as potential gut decolonization therapies for Kp.
Aoki, M.; Tsuchida, A.; Tamura, K.; Baba, O.; Yoshitake, K.; Furukawa, F.
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In many oviparous animals, egg yolk is the sole source of nutrition until feeding begins, and carbohydrates are present in only small amounts in the yolk. Glucose plays an important role in the developmental processes of various animals. In addition, gluconeogenesis has been reported to occur in the yolk syncytial layer (YSL) of cartilaginous fish and teleosts. In contrast, the role of gluconeogenesis in tetrapods remains unclear. In this study, we used Xenopus tropicalis, an anuran amphibian, which lacks YSL, and therefore provide an opportunity to examine the evolutionary conservation of gluconeogenic mechanisms among vertebrates. In X. tropicalis, liquid chromatography/mass spectrometry revealed that glucose levels increased before liver formation. Subsequent tracer experiments using 13C-labeled metabolic substrates detected gluconeogenesis activity from glycerol and lactate. Expression analyses showed that gluconeogenic genes are expressed in the epidermis and endoderm. Consistently, G0 knockout of fbp1, a key gluconeogenic gene, resulted in a significant reduction in glucose levels, affecting brain development. These findings first demonstrate that gluconeogenesis supports development of X. tropicalis. To the best of our knowledge, gluconeogenesis in developing epidermis has not been reported, highlighting previously unrecognized diversity in tissue-specific metabolism during vertebrate development. Comparative analyses across species will provide further insights into the evolution and functional significance of embryonic gluconeogenesis and nutrient metabolism.
Hoff, H.; Ijaz, S.; Echeverry, F. A.; Tetenborg, S.; Lin, Y.-P.; O'Brien, J.; Verselis, V.; Pereda, A. E.
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Electrical transmission is mediated by intercellular channels that cluster into structures known as gap junctions (GJ). In vertebrates, GJ channels are encoded by the gene family of connexin (Cx) proteins that assemble as hexamers, termed hemichannels, in the pre- and postsynaptic membranes, and that subsequently dock to form GJ channels. Auditory contacts on the fish Mauthner cells serve as model to study the properties and organization of vertebrate electrical synapses. Electrical transmission at these synapses is mediated by multiple co-existing GJs at which the presence of intercellular channels is regulated by a molecular scaffold. Zebrafish contain four homologs of the neuronal Cx36: Cx35.5 and Cx35.1 (gjd2a and b, respectively), and Cx34.1 and Cx34.7 (gjd1a and b). Cx mutations suggested that GJs are formed by heterotypic channels made of presynaptic Cx35.5 and postsynaptic Cx34.1. Using transgenic fish in which Cxs were tagged, we found that a second Cx, Cx34.7, is present together with Cx34.1 on the postsynaptic side at some but not all GJs at these terminals. When exogenously expressed, both Cx34.1 and Cx34.7 formed heterotypic functional channels with Cx35.5, each with substantially different voltage-dependent properties, indicating they can serve differential functions. However, we previously demonstrated that electrical transmission is lost in Cx34.1 but not Cx34.7 null mutants, suggesting that Cx34.7 cannot compensate for the loss of Cx34, despite the intrinsic ability of Cx34.1 and Cx34.7 to create functional channels. The findings reveal an unanticipated functional organization in the electrical synapse, where Cx34.1 is obligatory and Cx34.7 accessory, roles that appear to be defined by the postsynaptic molecular scaffold, with two postsynaptic Cxs possibly assembling under specific functional contexts. Thus, our results indicate that electrical synapses share an organizational motif with chemical synapses, akin to how they combine postsynaptic receptor types to modify synaptic function.
Wu, T.; Li, C.
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The genus Trichiurus is the most economically valuable fish in the family Trichiuridae, currently recognized to include 10 valid species. However, historically numerous morphologically similar congeners have been erroneously assigned as synonyms or subspecies of T. lepturus. In this study, we examined 16 hairtail specimens collected from the southern waters of Java Island, Indonesia. Integrated morphological and mitochondrial phylogenetic analyses (COX1 and 16S rRNA), compared against global Trichiurus sequences, revealed that these specimens form an independent lineage that diverged early from other congeners. Consequently, we describe this lineage as a previously undescribed cryptic species. Diagnostic characters include: first anal-fin spine below 36th-37th dorsal-fin rays; anus below 35th-36th dorsal-fin rays; anteriormost tip of supraoccipital well posterior to posterior distal margin of eye; anterior margin of the pectoral-fin spine non-serrated; fangs on both jaws with barb-like processes; upper jaw long, mean 16.6% (15.5-17.6%) of preanal length; snout short, 12.0% (10.9-13.1%) of preanal length; eye small, diameter 5.3% (4.3-5.7%) of preanal length; and absence of hyperostosis on dorsal cranium. We herein propose the name Trichiurus javaensis sp. nov., and provide a formal morphological description and diagnostic characterization of this species.
Xu, Z. q.; Gao, X.; Sun, J.; Jiang, M.; Zhu, J.; Geng, Y.; Jin, S.; Wang, Y.; Xu, Y. J.
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The activation of thermogenesis in brown adipose tissue (BAT) represents a pivotal target for ameliorating disorders of glucose and lipid metabolism. This study sought to elucidate the regulatory effects of quercetin on thermogenesis and glucose-lipid metabolism within brown adipocytes, alongside its underlying molecular mechanisms. The findings demonstrated that quercetin markedly upregulated the expression of uncoupling protein 1 (UCP1), a critical thermogenic protein in brown adipocytes, thereby enhancing cellular thermogenic capacity and effectively mitigating glucose and lipid metabolism disorders. Subsequent mechanistic investigations confirmed that quercetin activated the COX2-PGE2-EP4-UCP1 signaling axis by augmenting the stability of cyclooxygenase 2 (COX2) protein, thus mediating its thermogenic-promoting and metabolism-improving effects. This study identifies quercetin as a potential therapeutic agent for the improvement of glucose and lipid metabolism disorders, uncovers a novel molecular mechanism through which quercetin regulates brown adipocyte thermogenesis, and provides a theoretical and experimental foundation for the application of quercetin in the prevention and treatment of obesity and related metabolic diseases.
Welle, van der, R. E. N.; Jark, R.; Jans, J. J. M.; Verhoeven-Duif, N. M.; Klumperman, J.
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The tight regulation of iron homeostasis is of great importance for cellular health. An increase in intracellular iron levels results in the formation of free radicals, which damages macromolecules and membranes, eventually resulting in cell death by Ferroptosis. Recently, we showed that patients with mutations in VPS41 display a severe neurodegenerative phenotype with iron deposition in the brain. VPS41 is well known as subunit of the HOPS complex required for fusion of late endosomes and autophagosomes with lysosomes. However, VPS41 has also been identified as inhibitor of Ferroptosis and regulator of redox homeostasis. How VPS41 exerts these functions and if these are dependent on the HOPS complex is unknown. Here we show that depletion of VPS41 results in increased intracellular iron levels, ROS formation and mitochondrial fission. Our findings indicate an important role for VPS41 in the regulation of iron homeostasis and mitochondrial fission and suggest Ferroptosis as a possible cause for neurodegeneration in VPS41 patients.
Rehan, S. S.; Kiran, A.; Yasmeen, G.; Altaf, A.; Maqbool, M. T.; Hadi, F.; Aftab, S.
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Freshwater algae represent an underexplored source of naturally occurring bioactive metabolites with potential applications in pharmaceutical and biomedical research. This study investigated the phytochemical composition, antioxidant capacity, and preliminary cytotoxic potential of ethanolic and n-hexane extracts of freshwater algal species collected at Jilani Park, Lahore, Pakistan. Algal species were identified morphologically by Dr. Ghazal Yasmeen (Institute of Botany, Punjab University, Lahore). Extracts were analyzed using gas chromatography-mass spectrometry (GC-MS) and qualitative phytochemical screening. Antioxidant activity was evaluated using DPPH radical scavenging, hydrogen peroxide scavenging, and reducing power assays. Cytotoxic potential was assessed using MTT and cell adhesion assays on HeLa and SF767 cell lines as preliminary indicators of bioactivity. GC-MS analysis identified 25 compounds, including sterols, fatty acid esters, terpenoids, phenolic compounds, and volatile metabolites. Phytochemical screening confirmed the presence of flavonoids, phenolics, tannins, and terpenoids in the extracts. Among the tested extracts, the n-hexane fraction demonstrated comparatively higher antioxidant activity across multiple assays. Ethanolic extracts showed moderate reductions in HeLa cell viability, whereas limited effects were observed in SF767 cells. These findings suggest that freshwater algae are promising natural reservoirs of antioxidant metabolites with potential relevance for future isolation and characterization of bioactive compounds for biomedical applications. Further purification and mechanistic studies are required to identify specific active constituents.
Qazi, B.; Vishwakarma, V.; Kumar, V.; Pant, G.; Mitra, K.; Tripathi, R. K.; Haldar, S.
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The influenza virus poses a significant global health threat due to its continuous evolution, immune evasion, and zoonotic spillover. The rise of drug resistance, reduced susceptibility to existing antiviral medications, and the limited effectiveness of annual vaccines underscore the need for new antiviral strategies. To infect, the influenza virus binds to sialic acid (SA)-containing molecules on host cell membranes through hemagglutinin (HA). Blocking this interaction represents a promising antiviral approach. Herein, we report that SA containing plasma membrane-derived vesicles (PMV) efficiently inhibits in vitro Influenza A virus (IAV) infection. Using orthogonal methods, we demonstrate that PMV derived from A549, MDCK, and HEK cells competitively bind to H1N1 (WSN) and H3N2 (X-31) IAV strains, block entry and infection in human respiratory epithelial cells in a dose-dependent manner, without causing significant toxicity. When the size of the vesicles was reduced through extrusion, the antiviral activity was enhanced, and this was found to be correlated with a size-dependent increase in hemagglutination inhibition and reduced IAV internalisation. Plasma membrane-derived vesicles may serve as a novel antiviral strategy against influenza virus infections due to their simple production method and conserved SA binding site on HA.
Fadipe, J.; Okamura, T.; Yoshimura, S. H.; Saito, A.
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Many mammalian cells restrict viral replication by utilizing various host restriction factors. We recently demonstrated that CCHC-type zinc-finger-containing protein 3 (ZCCHC3) suppresses human immunodeficiency virus type 1 (HIV-1) replication through multiple mechanisms. We also revealed that single-nucleotide polymorphisms (SNPs) in human ZCCHC3 affect its antiviral function; however, whether similar genetic and functional diversity is present in other species remains unknown. In this study, we investigated the genetic and functional diversity of ZCCHC3 in cynomolgus macaques, a critical animal model for HIV-1-related research. Sequencing analysis of eight independent ZCCHC3 clones per animal revealed substantial amino acid diversity among cynomolgus macaques. We selected 12 representative variants and examined their antiviral activity against several retroviral vectors derived from HIV-1, simian immunodeficiency virus, feline immunodeficiency virus, and murine leukemia virus. Moreover, using replication-competent HIV-1, we showed that selected cynomolgus macaque ZCCHC3 variants can affect both viral production and viral infectivity. These results suggest that the genetic and functional diversity of ZCCHC3 is not limited to humans and underscore the importance of considering ZCCHC3 variation in cynomolgus macaques when using them as animal models for HIV-1-related research.