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1.
FASEB J ; 38(6): e23572, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38512139

RESUMO

Asthma is characterized by airway remodeling and hyperreactivity. Our earlier studies determined that the nitric oxide (NO)-soluble guanylyl cyclase (sGC)-cGMP pathway plays a significant role in human lung bronchodilation. However, this bronchodilation is dysfunctional in asthma due to high NO levels, which cause sGC to become heme-free and desensitized to its natural activator, NO. In order to determine how asthma impacts the various lung segments/lobes, we mapped the inflammatory regions of lungs to determine whether such regions coincided with molecular signatures of sGC dysfunction. We demonstrate using murine models of asthma (OVA and CFA/HDM) that the inflamed segments of these murine lungs can be tracked by upregulated expression of HO1 and these regions in turn overlap with regions of heme-free sGC as evidenced by a decreased sGC-α1ß1 heterodimer and an increased response to heme-independent sGC activator, BAY 60-2770, relative to naïve uninflamed regions. We also find that NO generated from iNOS upregulation in the inflamed segments has a higher impact on developing heme-free sGC as increasing iNOS activity correlates linearly with elevated heme-independent sGC activation. This excess NO works by affecting the epithelial lung hemoglobin (Hb) to become heme-free in asthma, thereby causing the Hb to lose its NO scavenging function and exposing the underlying smooth muscle sGC to excess NO, which in turn becomes heme-free. Recognition of these specific lung segments enhances our understanding of the inflamed lungs in asthma with the ultimate aim to evaluate potential therapies and suggest that regional and not global inflammation impacts lung function in asthma.


Assuntos
Asma , Heme Oxigenase-1 , Heme , Animais , Humanos , Camundongos , Alérgenos , Heme Oxigenase-1/metabolismo , Inflamação , Óxido Nítrico , Guanilil Ciclase Solúvel
2.
J Biomol Struct Dyn ; : 1-15, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38321949

RESUMO

Toxin-antitoxin (TA) modules, initially discovered on bacterial plasmids and subsequently identified within chromosomal contexts, hold a pivotal role in the realm of bacterial physiology. Among these, the pioneering TA system, ccd (Control of Cell Death), primarily localized on the F-plasmid, is known for its orchestration of plasmid replication with cellular division. Nonetheless, the precise functions of such systems within bacterial chromosomal settings remain a compelling subject that demands deeper investigation. To bridge this knowledge gap, our study focuses on exploring ccdABXn2, a chromosomally encoded TA module originating from the entomopathogenic bacterium Xenorhabdus nematophila. We meticulously delved into the system's genomic assignments, structural attributes, and functional interplay. Our findings uncovered intriguing patterns-CcdB toxin homologs exhibited higher conservation levels compared to their CcdA antitoxin counterparts. Moreover, we constructed secondary as well as tertiary models for both the CcdB toxin and CcdA antitoxin using threading techniques and subsequently validated their structural integrity. Our exploration extended to the identification of key interactions, including the peptide interaction with gyrase for the CcdB homolog and CcdB toxin interactions for the CcdA homolog, highlighting the intricate TA interaction network. Through docking and simulation analyses, we unequivocally demonstrated the inhibition of replication via binding the CcdB toxin to its target, DNA gyrase. These insights provide valuable knowledge about the metabolic and physiological roles of the chromosomally encoded ccdABXn2 TA module within the context of X. nematophila, significantly enhancing our comprehension of its functional significance within the intricate ecosystem of the bacterial host.Communicated by Ramaswamy H. Sarma.

3.
Heliyon ; 10(1): e23693, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38187285

RESUMO

A novel and distinct mutant with a phenotype, aeroplane wing (ae) is reported for the first time in the urban malaria vector Anopheles stephensi. The main aim of this study was to establish the mode of inheritance of the ae gene performing genetic crossings between the mutants and wild types. These mutants show extended open wings that are visible to naked eyes in both the sexes. Mutants were first noticed in a nutritionally stressed isofemale colony. Strategic genetic crosses revealed that the ae gene is a recessive, autosomal, and monogenic trait having full penetrance with uniform expression in its adult stage. Egg morphometric analysis confirmed that these mutants were intermediate variant. No significant differences were observed in the wing venation and size of ae mutants compared to their control parental lines. Further cytogenetic analysis on the ovarian polytene chromosome of ae mutant showed an inversion (3Li) on the 3L arm like its parental line. This ae mutant would be a prominent marker and could be useful to study the functions of related specific genes within its genome.

4.
bioRxiv ; 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38076947

RESUMO

Asthma is characterized by airway remodeling and hyperreactivity. Our earlier studies determined that the Nitric Oxide (NO)-soluble Guanylyl Cyclase (sGC)-cGMP pathway plays a significant role in human lung bronchodilation. However this bronchodilation is dysfunctional in asthma due to high NO levels which cause sGC to become heme-free and desensitized to its natural activator, NO. In order to determine how asthma impacts the various lung segments/lobes we mapped the inflammatory regions of lungs to determine whether such regions coincided with molecular signatures of sGC dysfunction. We demonstrate using models of mouse asthma (OVA, CFA/HDM) that the inflammed segments of the mouse asthma lungs can be tracked by upregulated expression of HO1 and these regions in-turn overlap with regions of heme-free sGC as evidenced by a decreased sGC-α1ß1 heterodimer and an increased response to heme-independent sGC activator, BAY 60-2770 relative to naïve uninflamed regions. We also find that NO generated from iNOS upregulation in the inflamed segments has a higher impact in developing heme-free sGC as increasing iNOS activity correlates linearly with elevated heme-independent sGC activation. This excess NO works by affecting the epithelial lung hemoglobin (Hb) to become heme-free in asthma thereby causing the Hb to lose its NO scavenging function and exposing the underlying smooth muscle sGC to excess NO, which in-turn becomes heme-free. Recognition of these specific lung segments enhance our understanding of the inflammed lungs in asthma with the ultimate aim to evaluate potential therapies and suggests that regional and not global inflammation impacts lung function in asthma.

5.
Reprod Sci ; 30(11): 3359-3371, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37286756

RESUMO

Infertility affects 15% of global population. This study was designed to search out the most effective dose of chloroform fraction of hydro-ethanolic extract of Hygrophila auriculata seed to ameliorate cyproterone acetate (CPA)-treated male subfertility. The rats were made subfertile by CPA at the dose of 2.5 mg/100gm body weight for 45 days. The male subfertility represented by low sperm concentration, less motile, less viable, and less hypo osmotic tail swelled spermatozoa in CPA-treated group. Serum LH, FSH, and testosterone levels were significantly decreased in CPA-treated group in respect to control. Androgenic key enzyme Δ5,3ß-HSD, 17ß-HSD activities and gene expression pattern were also decreased significantly in respect to control. These antispermatogenic and antiandrogenic activities of CPA were significantly recovered after the treatment of Hygrophila auriculata at the dose of 2.5 mg, 5mg, and 10 mg/100gm body weight. CPA also generate oxidative free radical that indicated by altered catalase, superoxide dismutase, and peroxidase activities and protein expression pattern along with conjugated diene and thiobarbituric acid reactive substance levels in testis. Expression pattern of Bax and Bcl2 genes were deviated from control after CPA treatment. Significant diminution of body weight, organo-somatic indices, and SGOT, SGPT activities were observed in CPA-treated group. All these biomarkers significantly recovered towards control after the treatment of Hygrophila auriculata at different doses. More significant recovery was observed in 5 mg and 10 mg of chloroform fraction-treated group and 5 mg dose, i.e., the minimum therapeutic dose to recover the CPA-induced subfertility.


Assuntos
Acanthaceae , Infertilidade Masculina , Humanos , Masculino , Ratos , Animais , Acetato de Ciproterona/efeitos adversos , Acetato de Ciproterona/metabolismo , Testosterona , Clorofórmio/efeitos adversos , Clorofórmio/metabolismo , Sementes , Testículo/metabolismo , Infertilidade Masculina/metabolismo , Peso Corporal , Estresse Oxidativo
6.
Parasit Vectors ; 16(1): 79, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36855157

RESUMO

BACKGROUND: Vector management programs rely on knowledge of the biology and genetic make-up of mosquitoes. Anopheles stephensi is a major invasive urban malaria vector, distributed throughout the Indian subcontinent and Middle East, and has recently been expanding its range in Africa. With the existence of three biological forms, distinctly identifiable based on the number of ridges on eggs and varying vectorial competence, An. stephensi is a perfect species for developing isofemale lines, which can be tested for insecticide susceptibility and vectorial competence of various biological forms. METHODS: We describe key steps involved in establishment and validation of isofemale lines. Isofemale colonies were further used for the characterization of insecticide susceptibility and differential vector competence. The results were statistically evaluated through descriptive and inferential statistics using Vassar Stat and Prism GraphPad software packages. RESULTS: Through a meticulous selection process, we overcame an initial inbreeding depression and found no significant morphometric differences in wings and egg size between the parental and respective isofemale lines in later generations. IndCh and IndInt strains showed variations in resistance to different insecticides belonging to all four major classes. We observed a significant change in vectorial competence between the respective isofemale and parental lines. CONCLUSIONS: Isofemale lines can be a valuable resource for characterizing and enhancing several genotypic and phenotypic traits. This is the first detailed report of the establishment of two isofemale lines of type and intermediate biological forms in Anopheles stephensi. The work encompasses characterization of fitness traits among two lines through a transgenerational study. Furthermore, isofemale colonies were established and used to characterize insecticide susceptibility and vector competence. The study provides valuable insights into differential susceptibility status of the parental and isofemale lines to different insecticides belonging to the same class. Corroborating an earlier hypothesis, we demonstrate the high vector competence of the type form relative to the intermediate form using homozygous lines. Using these lines, it is now possible to study host-parasite interactions and identify factors that might be responsible for altered susceptibility and increased vector competence in An. stephensi biological forms that would also pave the way for developing better vector management strategies.


Assuntos
Anopheles , Inseticidas , Malária , Animais , Anopheles/genética , Inseticidas/farmacologia , Malária/prevenção & controle , Mosquitos Vetores/genética , Fenótipo
7.
Front Pharmacol ; 13: 983233, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36515436

RESUMO

Polytherapy with antiseizure medications (ASMs) is often used to control seizures in patients suffering from epilepsy, where about 30% of patients are pharmacoresistant. While drug combinations are intended to be beneficial, the consequence of CYP-dependent drug interactions on apoptotic protein levels and mitochondrial function in the epileptic brain remains unclear. We examined the interactions of ASMs given prior to surgery in surgically resected brain tissues and of three ASMs (lacosamide, LCM; oxcarbazepine, OXC; levetiracetam LEV) in isolated brain cells from patients with drug-resistant epilepsy (n = 23). We divided the patients into groups-those who took combinations of NON-CYP + CYP substrate ASMs, NON-CYP + CYP inducer ASMs, CYP substrate + CYP substrate or CYP substrate + CYP inducer ASMs-to study the 1) pro- and anti-apoptotic protein levels and other apoptotic signaling proteins and levels of reactive oxygen species (reduced glutathione and lipid peroxidation) in brain tissues; 2) cytotoxicity at blood-brain barrier epileptic endothelial cells (EPI-ECs) and subsequent changes in mitochondrial membrane potential in normal neuronal cells, following treatment with LCM + OXC (CYP substrate + CYP inducer) or LCM + LEV (CYP substrate + NON-CYP-substrate) after blood-brain barrier penetration, and 3) apoptotic and mitochondrial protein targets in the cells, pre-and post-CYP3A4 inhibition by ketoconazole and drug treatments. We found an increased BAX (pro-apoptotic)/Bcl-XL (anti-apoptotic) protein ratio in epileptic brain tissue after treatment with CYP substrate + CYP substrate or inducer compared to NON-CYP + CYP substrate or inducer, and subsequently decreased glutathione and elevated lipid peroxidation levels. Further, increased cytotoxicity and Mito-ID levels, indicative of compromised mitochondrial membrane potential, were observed after treatment of LCM + OXC in combination compared to LCM + LEV or these ASMs alone in EPI-ECs, which was attenuated by pre-treatment of CYP inhibitor, ketoconazole. A combination of two CYP-mediated ASMs on EPI-ECs resulted in elevated caspase-3 and cytochrome c with decreased SIRT3 levels and activity, which was rescued by CYP inhibition. Together, the study highlights for the first time that pro- and anti-apoptotic proteins levels are dependent on ASM combinations in epilepsy, modulated via a CYP-mediated mechanism that controls free radicals, cytotoxicity and mitochondrial activity. These findings lead to a better understanding of future drug selection choices offsetting pharmacodynamic CYP-mediated interactions.

8.
Sci Rep ; 12(1): 19079, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36351999

RESUMO

Identification of Plasmodium-resistance genes in malaria vectors remains an elusive goal despite the recent availability of high-quality genomes of several mosquito vectors. Anopheles stephensi, with its three distinctly-identifiable forms at the egg stage, correlating with varying vector competence, offers an ideal species to discover functional mosquito genes implicated in Plasmodium resistance. Recently, the genomes of several strains of An. stephensi of the type-form, known to display high vectorial capacity, were reported. Here, we report a chromosomal-level assembly of an intermediate-form of An. stephensi strain (IndInt), shown to have reduced vectorial capacity relative to a strain of type-form (IndCh). The contig level assembly with a L50 of 4 was scaffolded into chromosomes by using the genome of IndCh as the reference. The final assembly shows a heterozygous paracentric inversion, 3Li, involving 8 Mbp, which is syntenic to the extensively-studied 2La inversion implicated in Plasmodium resistance in An. gambiae involving 21 Mbp. Deep annotation of genes within the 3Li region in the IndInt assembly using the state-of-the-art protein-fold prediction and other annotation tools reveals the presence of a tumor necrosis factor-alpha (TNF-alpha) like gene, which is the homolog of the Eiger gene in Drosophila. Subsequent chromosome-wide searches revealed homologs of Wengen (Wgn) and Grindelwald (Grnd) genes, which are known to be the receptors for Eiger in Drosophila. We have identified all the genes in IndInt required for Eiger-mediated signaling by analogy to the TNF-alpha system, suggesting the presence of a functionally-active Eiger signaling pathway in IndInt. Comparative genomics of the three type-forms with that of IndInt, reveals structurally disruptive mutations in Eiger gene in all three strains of the type-form, suggesting compromised innate immunity in the type-form as the likely cause of high vectorial capacity in these strains. This is the first report of the presence of a homolog of Eiger in malaria vectors, known to be involved in cell death in Drosophila, within an inversion region in IndInt syntenic to an inversion associated with Plasmodium resistance in An. gambiae.


Assuntos
Anopheles , Malária , Plasmodium , Animais , Anopheles/genética , Mosquitos Vetores/genética , Fator de Necrose Tumoral alfa/genética , Plasmodium/genética , Inversão Cromossômica , Drosophila
9.
Front Neurol ; 13: 942643, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36188379

RESUMO

Objective: Seizure outcomes after brain surgery for drug-resistant epilepsy (DRE) are very heterogeneous and difficult to predict with models utilizing the current clinical, imaging, and electrophysiological variables. In this pilot study, we investigated whether genetic and molecular biomarkers (e.g., genomic, transcriptomic) can provide additional insight into differential response to surgery. Methods: Post-operative seizure-outcomes were collected at last follow-up (>6 months) for 201 adult patients with DRE who underwent surgery between 2004 and 2020. Resected tissue was sent for miRNA sequencing (n = 132) and mRNA sequencing (n = 135). Following the selection of 10 genes (SCN1A, NBEA, PTEN, GABRA1, LGL1, DEPDC5, IL1A, ABCB1, C3, CALHM1), we investigated SNPs in those 10 genes from previously acquired exome sequencing data (n = 106). Logistic regression was performed to test for associations between individual features (mRNAs, miRNAs, and SNPs) and post-operative seizure-outcome with an exploratory FDR P < 0.25 as the threshold for significance. Post-operative time-to-seizure analyses were performed for each SNP using a Cox proportional hazards model. Results: The majority of patients (83%) had temporal lobe epilepsy. Mean age at surgery was 38.3 years, and 56% were female. Three SNPs (rs10276036, rs11975994, rs1128503) in multi-drug resistance gene, ABCB1, were associated with post-operative seizure outcomes. Patients with alternate alleles in ABCB1 were more likely to be seizure-free at last follow-up (52-56% reduction in seizure recurrence; FDR P = 0.24). All three SNPs were in linkage disequilibrium and highly correlated with each other. Median post-operative time-to-seizure was 63 months for patients with 2 alternate alleles, 24-33 months with 1 alternate allele, and 10-11 months with 0 alternate alleles. These SNPs improved outcome prediction beyond MRI and sex alone. No independent miRNAs or mRNAs were significantly associated with seizure-outcome (P > 0.05). However, pathway analysis identified "cancer drug resistance by drug efflux" (mir-154 and mir-379) as enriched (P = 0.02), supporting the role of drug response genes in post-operative seizure recurrence. Significance: ABCB1 may have a role in epileptogenesis and surgery outcomes independent of its drug efflux activity necessitating further investigation. SNPs in ABCB1 may serve as independent predictors of post-operative outcome.

10.
Int J Mol Sci ; 23(9)2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35563330

RESUMO

The glucocorticoid receptor (GR) at the blood−brain barrier (BBB) is involved in the pathogenesis of drug-resistant epilepsy with focal cortical dysplasia (FCD); however, the roles of GR isoforms GRα and GRß in the dysplastic brain have not been revealed. We utilized dysplastic/epileptic and non-dysplastic brain tissue from patients who underwent resective epilepsy surgery to identify the GRα and GRß levels, subcellular localization, and cellular specificity. BBB endothelial cells isolated from the dysplastic brain tissue (EPI-ECs) were used to decipher the key BBB proteins related to drug regulation and BBB integrity compared to control and transfected GRß-overexpressed BBB endothelial cells. GRß was upregulated in dysplastic compared to non-dysplastic tissues, and an imbalance of the GRα/GRß ratio was significant in females vs. males and in patients > 45 years old. In EPI-ECs, the subcellular localization and expression patterns of GRß, Hsp90, CYP3A4, and CYP2C9 were consistent with GRß+ brain endothelial cells. Active matrix metalloproteinase levels and activity increased, whereas claudin-5 levels decreased in both EPI-ECs and GRß+ endothelial cells. In conclusion, the GRß has a major effect on dysplastic BBB functional proteins and is age and gender-dependent, suggesting a critical role of brain GRß in dysplasia as a potential biomarker and therapeutic target in epilepsy.


Assuntos
Epilepsia , Receptores de Glucocorticoides , Barreira Hematoencefálica , Encéfalo/metabolismo , Encéfalo/patologia , Células Endoteliais/metabolismo , Epilepsia/tratamento farmacológico , Epilepsia/metabolismo , Feminino , Glucocorticoides/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Receptores de Glucocorticoides/efeitos dos fármacos , Receptores de Glucocorticoides/metabolismo
11.
Sci Rep ; 12(1): 3610, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-35246568

RESUMO

Anopheles stephensi is the most menacing malaria vector to watch for in newly urbanising parts of the world. Its fitness is reported to be a direct consequence of the vector adapting to laying eggs in over-head water tanks with street-side water puddles polluted by oil and sewage. Large frequent inversions in the genome of malaria vectors are implicated in adaptation. We report the genome assembly of a strain of An. stephensi of the type-form, collected from a construction site from Chennai (IndCh) in 2016. The genome reported here with a L50 of 4, completes the trilogy of high-resolution genomes of strains with respect to a 16.5 Mbp 2Rb genotype in An. stephensi known to be associated with adaptation to environmental heterogeneity. Unlike the reported genomes of two other strains, STE2 (2R+b/2Rb) and UCI (2Rb/2Rb), IndCh is found to be homozygous for the standard form (2R+b/2R+b). Comparative genome analysis revealed base-level details of the breakpoints and allowed extraction of 22,650 segregating SNPs for typing this inversion in populations. Whole genome sequencing of 82 individual mosquitoes from diverse geographical locations reveal that one third of both wild and laboratory populations maintain the heterozygous genotype of 2Rb. The large number of SNPs can be tailored to 1740 exonic SNPs enabling genotyping directly from transcriptome sequencing. The genome trilogy approach accelerated the study of fine structure and typing of an important inversion in An. stephensi, putting the genome resources for this understudied species on par with the extensively studied malaria vector, Anopheles gambiae. We argue that the IndCh genome is relevant for field translation work compared to those reported earlier by showing that individuals from diverse geographical locations cluster with IndCh, pointing to significant convergence resulting from travel and commerce between cities, perhaps, contributing to the survival of the fittest strain.


Assuntos
Anopheles , Malária , Animais , Anopheles/genética , Inversão Cromossômica , Índia , Mosquitos Vetores/genética , Água
12.
Mol Neurobiol ; 59(4): 2389-2406, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35084654

RESUMO

Focal cortical dysplasia (FCD) is associated with blood-brain barrier (BBB) dysfunction in patients with difficult-to-treat epilepsy. However, the underlying cellular and molecular factors in cortical dysplasia (CD) associated with progressive neurovascular challenges during the pro-epileptic phase, post-seizure, and during epileptogenesis remain unclear. We studied the BBB function in a rat model of congenital (in utero radiation-induced, first hit) CD and longitudinally examined the cortical brain tissues at baseline and the progressive neurovascular alterations, glucose transporter-1 (GLUT1) expression, and glucose metabolic activity at 2, 15, and 30 days following a second hit using pentylenetetrazole-induced seizure. Our study revealed through immunoblotting, immunohistochemistry, and biochemical analysis that (1) altered vascular density and prolongation of BBB albumin leakages in CD rats continued through 30 days post-seizure; (2) CD brain tissues showed elevated matrix metalloproteinase-9 levels at 2 days post-seizure and microglial overactivation through 30 days post-seizure; (3) BBB tight junction protein and GLUT1 levels were decreased and neuronal monocarboxylate transporter-2 (MCT2) and mammalian target of rapamycin (mTOR) levels were increased in the CD rat brain: (4) ATPase activity is elevated and a low glucose/high lactate imbalance exists in CD rats; and (5) the mTOR pathway is activated and MCT2 levels are elevated in the presence of high lactate during glucose starvation in vitro. Together, this study suggests that BBB dysfunction, including decreased GLUT1 expression and metabolic disturbance, may contribute to epileptogenesis in this CD rat model through multiple mechanisms that could be translated to FCD therapy in medically refractory epilepsy.


Assuntos
Epilepsia , Malformações do Desenvolvimento Cortical , Animais , Barreira Hematoencefálica/metabolismo , Glucose/metabolismo , Transportador de Glucose Tipo 1/metabolismo , Ácido Láctico , Mamíferos/metabolismo , Ratos , Convulsões , Serina-Treonina Quinases TOR/metabolismo
13.
Biomedicines ; 9(12)2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34944650

RESUMO

Due to the physiological and structural properties of the blood-brain barrier (BBB), the delivery of drugs to the brain poses a unique challenge in patients with central nervous system (CNS) disorders. Several strategies have been investigated to circumvent the barrier for CNS therapeutics such as in epilepsy, stroke, brain cancer and traumatic brain injury. In this review, we summarize current and novel routes of drug interventions, discuss pharmacokinetics and pharmacodynamics at the neurovascular interface, and propose additional factors that may influence drug delivery. At present, both technological and mechanistic tools are devised to assist in overcoming the BBB for more efficient and improved drug bioavailability in the treatment of clinically devastating brain disorders.

14.
Curr Res Microb Sci ; 2: 100047, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34841338

RESUMO

Toxin-antitoxin (TA) modules are ubiquitous gene loci among bacteria and are comprised of a toxin part and its cognate antitoxin part. Under normal physiological conditions, antitoxin counteracts the toxicity of the toxin whereas, during stress conditions, TA modules play a crucial role in bacterial physiology through involvement in the post-segregational killing, abortive infection, biofilms, and persister cell formation. Most of the toxins are proteinaceous that affect translation or DNA replication, although some other intracellular molecular targets have also been described. While antitoxins may be a protein or RNA, that generally neutralizes its cognate toxin by direct interaction or with the help of other signaling elements and thus helps in the TA module regulation. In this review, we have discussed the current state of the multifaceted TA (type I-VIII) modules by highlighting their classification and specific targets. We have also discussed the presence of TA modules in the various pathogens and their role in antibiotic persistence development as well as biofilm formation, by influencing the different cellular processes. In the end, assembling knowledge about ubiquitous TA systems from pathogenic bacteria facilitated us to propose multiple novel antibacterial strategies involving artificial activation of TA modules.

15.
J Food Biochem ; : e13859, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34258791

RESUMO

This study investigated the gastroprotective effect of Ayapana triplinervis leaves against indomethacin-induced gastric ulcer in male albino rat. Gastric ulceration was developed by single oral dose of indomethacin (30 mg/kg). Experimental rats were pretreated with omeprazole (positive control 20 mg/kg), hydromethanolic extract of A. triplinervis (200 mg/kg) for 28 days just before the indomethacin treatment. Free acidity, total acidity, pepsin activity and gastric volume, gastric pH, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) in stomach and serum prostaglandin E2 levels were assessed in control, ulcerated group and A. triplinervis pretreated groups. Oxidative stress biomarkers, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in serum also evaluated. All the parameters were deviated from control in indomethacin-treated group but significantly protected in A. triplinervis-pretreated group. The active ingredient(s) present in the A. triplinervis have antioxidant and gastroprotective properties that prevent the indomethacin-induced gastric ulcer. PRACTICAL APPLICATIONS: A. triplinervis has been widely consumed from earlier time as traditional medicine for the treatment of gastric problem and gastric ulcer in India. This is the first report that hydromethanolic extract of A. triplinervis has potent therapeutic properties against gastric ulcer. This work will provide a clue to the pharmaceutical industry to develop an effective gastroprotective agent.

17.
Arch Gynecol Obstet ; 303(2): 419-426, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32897400

RESUMO

OBJECTIVE: Many modifiable maternal behaviors and experiences before and during pregnancy are associated with adverse health outcomes. The relationship between a number of maternal and gestational disorders and perinatal outcomes (preterm birth, low birth weight and neonatal intensive care unit (NICU)) admission in the Central New York population is determined using the Statewide Perinatal Data System, in a retrospective population-based cohort study. METHODS: Singleton births excluding newborns with congenital anomalies among 165,739 women between 2004 and 2012 are included in this study. Multivariable logistic regression analysis is used to estimate odds ratios (OR) and 95% confidence intervals (CI) adjusted for maternal age, race, education, employment, parity, body mass index, smoking, drug use, depression, abortions, gender of child, prenatal care, and hospital level. RESULTS: Previous preterm birth and vaginal bleeding are independent high-risk factors for all three perinatal outcomes, pre-pregnancy diabetes (OR 4.95, 95% CI 4.34, 5.64) for preterm birth and (OR 7.45, 95% CI 6.58, 8.44) for NICU admission; and gestational hypertension (OR 4.35, 95% CI 4.03, 4.70) for low birth weight. Among infections, bacterial vaginosis is retained in the multivariable model as a risk factor for preterm and low birth weight while hepatitis C is a risk factor for NICU admission. CONCLUSIONS: Our findings suggest the continued importance of addressing the need to provide preconception and inter conception care for women since many modifiable risk factors are correlated and need to be addressed well before the woman becomes pregnant.


Assuntos
Hipertensão Induzida pela Gravidez/epidemiologia , Recém-Nascido de Baixo Peso , Unidades de Terapia Intensiva Neonatal/estatística & dados numéricos , Pré-Eclâmpsia/epidemiologia , Gravidez em Diabéticas/epidemiologia , Nascimento Prematuro/epidemiologia , Adulto , Peso ao Nascer , Estudos de Coortes , Feminino , Humanos , Recém-Nascido , Idade Materna , Paridade , Gravidez , Cuidado Pré-Natal , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
18.
Curr Comput Aided Drug Des ; 17(3): 402-411, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32586257

RESUMO

BACKGROUND: Xenorhabdus nematophila maintains species-specific mutual interaction with nematodes of Steinernema genus. Type II Toxin Antitoxin (TA) systems, the mazEF TA system controls stress and programmed cell death in bacteria. OBJECTIVE: This study elucidates the functional characterization of Xn-mazEF, a mazEF homolog in X. nematophila by computational and in vitro approaches. METHODS: 3D- structural models for Xn-MazE toxin and Xn-MazF antitoxin were generated, validated and characterized for protein - RNA interaction analysis. Further biological and cellular functions of Xn-MazF toxin were also predicted. Molecular dynamics simulations of 50ns for Xn- MazF toxin complexed with nucleic acid units (DU, RU, RC, and RU) were performed. The MazF toxin and complete MazEF operon were endogenously expressed and monitored for the killing of Escherichia coli host cells under arabinose induced tightly regulated system. RESULTS: Upon induction, E. coli expressing toxin showed rapid killing within four hours and attained up to 65% growth inhibition, while the expression of the entire operon did not show significant killing. The observation suggests that the Xn-mazEF TA system control transcriptional regulation in X. nematophila and helps to manage stress or cause toxicity leading to programmed death of cells. CONCLUSION: The study provides insights into structural and functional features of novel toxin, Xn- MazF and provides an initial inference on control of X. nematophila growth regulated by TA systems.


Assuntos
Proteínas de Bactérias/fisiologia , Proteínas de Ligação a DNA/metabolismo , Endorribonucleases/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/fisiologia , Sistemas Toxina-Antitoxina/fisiologia , Apoptose/fisiologia , Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/genética , Endorribonucleases/genética , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Simulação de Dinâmica Molecular , Óperon/genética , Fatores de Tempo , Sistemas Toxina-Antitoxina/genética , Xenorhabdus
19.
Front Genet ; 11: 565626, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33312190

RESUMO

Malaria remains a major healthcare risk to growing economies like India, and a chromosome-level reference genome of Anopheles stephensi is critical for successful vector management and understanding of vector evolution using comparative genomics. We report chromosome-level assemblies of an Indian strain, STE2, and a Pakistani strain SDA-500 by combining draft genomes of the two strains using a homology-based iterative approach. The resulting assembly IndV3/PakV3 with L50 of 9/12 and N50 6.3/6.9 Mb had scaffolds long enough for building 90% of the euchromatic regions of the three chromosomes, IndV3s/PakV3s, using low-resolution physical markers and enabled the generation of the next version of genome assemblies, IndV4/PakV4, using HiC data. We have validated these assemblies using contact maps against publicly available HiC raw data from two strains including STE2 and another lab strain of An. stephensi from UCI and compare the quality of the assemblies with other assemblies made available as preprints since the submission of the manuscript. We show that the IndV3s and IndV4 assemblies are sensitive in identifying a homozygous 2Rb inversion in the UCI strain and a 2Rb polymorphism in the STE2 strain. Multiple tandem copies of CYP6a14, 4c1, and 4c21 genes, implicated in insecticide resistance, lie within this inversion locus. Comparison of assembled genomes suggests a variation of 1 in 81 positions between the UCI and STE2 lab strains, 1 in 82 between SDA-500 and UCI strain, and 1 in 113 between SDA-500 and STE2 strains of An. stephensi, which are closer than 1 in 68 variations among individuals from two other lab strains sequenced and reported here. Based on the developmental transcriptome and orthology of all the 54 olfactory receptors (ORs) to those of other Anopheles species, we identify an OR with the potential for host recognition in the genus Anopheles. A comparative analysis of An. stephensi genomes with the completed genomes of a few other Anopheles species suggests limited inter-chromosomal gene flow and loss of synteny within chromosomal arms even among the closely related species.

20.
Cells ; 9(11)2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-33120941

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel human coronavirus that has sparked a global pandemic of the coronavirus disease of 2019 (COVID-19). The virus invades human cells through the angiotensin-converting enzyme 2 (ACE2) receptor-driven pathway, primarily targeting the human respiratory tract. However, emerging reports of neurological manifestations demonstrate the neuroinvasive potential of SARS-CoV-2. This review highlights the possible routes by which SARS-CoV-2 may invade the central nervous system (CNS) and provides insight into recent case reports of COVID-19-associated neurological disorders, namely ischaemic stroke, encephalitis, encephalopathy, epilepsy, neurodegenerative diseases, and inflammatory-mediated neurological disorders. We hypothesize that SARS-CoV-2 neuroinvasion, neuroinflammation, and blood-brain barrier (BBB) dysfunction may be implicated in the development of the observed disorders; however, further research is critical to understand the detailed mechanisms and pathway of infectivity behind CNS pathogenesis.


Assuntos
Betacoronavirus/metabolismo , Barreira Hematoencefálica/fisiopatologia , Barreira Hematoencefálica/virologia , Infecções por Coronavirus/complicações , Doenças do Sistema Nervoso/complicações , Pneumonia Viral/complicações , Internalização do Vírus , Enzima de Conversão de Angiotensina 2 , Betacoronavirus/imunologia , COVID-19 , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Citocinas/metabolismo , Humanos , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , SARS-CoV-2
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