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1.
Cell Immunol ; 399-400: 104826, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38669897

RESUMO

Infectious diseases like leishmaniasis, malaria, HIV, tuberculosis, leprosy and filariasis are responsible for an immense burden on public health systems. Among these, leishmaniasis is under the category I diseases as it is selected by WHO (World Health Organization) on the ground of diversity and complexity. High cost, resistance and toxic effects of Leishmania traditional drugs entail identification and development of therapeutic alternative. Since the natural infection elicits robust immunity, consistence efforts are going on to develop a successful vaccine. Clinical trials have been conducted on vaccines like Leish-F1, F2, and F3 formulated using specific Leishmania antigen epitopes. Current strategies utilize individual or combined antigens from the parasite or its insect vector's salivary gland extract, with or without adjuvant formulation for enhanced efficacy. Promising animal data supports multiple vaccine candidates (Lmcen-/-, LmexCen-/-), with some already in or heading for clinical trials. The crucial challenge in Leishmania vaccine development is to translate the research knowledge into affordable and accessible control tools that refines the outcome for those who are susceptible to infection. This review focuses on recent findings in Leishmania vaccines and highlights difficulties facing vaccine development and implementation.


Assuntos
Leishmania , Vacinas contra Leishmaniose , Leishmaniose , Desenvolvimento de Vacinas , Humanos , Vacinas contra Leishmaniose/imunologia , Animais , Leishmania/imunologia , Leishmaniose/imunologia , Leishmaniose/prevenção & controle , Desenvolvimento de Vacinas/métodos , Antígenos de Protozoários/imunologia , Ensaios Clínicos como Assunto
2.
Front Cell Dev Biol ; 12: 1356421, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495618

RESUMO

Signal regulatory protein-α (SIRPα, SHPS-1, CD172a) expressed on myeloid cells transmits inhibitory signals when it engages its counter-receptor CD47 on an adjacent cell. Elevated CD47 expression on some cancer cells thereby serves as an innate immune checkpoint that limits phagocytic clearance of tumor cells by macrophages and antigen presentation to T cells. Antibodies and recombinant SIRPα constructs that block the CD47-SIRPα interaction on macrophages exhibit anti-tumor activities in mouse models and are in ongoing clinical trials for treating several human cancers. Based on prior evidence that engaging SIRPα can also alter CD47 signaling in some nonmalignant cells, we compared direct effects of recombinant SIRPα-Fc and a humanized CD47 antibody that inhibits CD47-SIRPα interaction (CC-90002) on CD47 signaling in cancer stem cells derived from the MDA-MB- 231 triple-negative breast carcinoma cell line. Treatment with SIRPα-Fc significantly increased the formation of mammospheres by breast cancer stem cells as compared to CC-90002 treatment or controls. Furthermore, SIRPα-Fc treatment upregulated mRNA and protein expression of ALDH1 and altered the expression of genes involved in epithelial/mesenchymal transition pathways that are associated with a poor prognosis and enhanced metastatic activity. This indicates that SIRPα-Fc has CD47-mediated agonist activities in breast cancer stem cells affecting proliferation and metastasis pathways that differ from those of CC-90002. This SIRPα-induced CD47 signaling in breast carcinoma cells may limit the efficacy of SIRPα decoy therapeutics intended to stimulate innate antitumor immune responses.

3.
Biol Psychiatry ; 95(3): 220-230, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37673411

RESUMO

BACKGROUND: Both psychostimulant use and engagement with probabilistic schedules of reward sensitize the mesocorticolimbic dopamine (DA) system. Such behaviors may act synergistically to explain the high comorbidity between stimulant use and gambling disorder. The salient audiovisual stimuli of modern electronic gambling may exacerbate the situation. METHODS: To probe these interactions, we sensitized ventral tegmental area DA neurons via chronic chemogenetic stimulation while rats (n = 134) learned a rat gambling task in the presence or absence of casino-like cues. The same rats then learned to self-administer cocaine. In a separate cohort (n = 25), we confirmed that our chemogenetic methods sensitized the locomotor response to cocaine and potentiated phasic excitability of ventral tegmental area DA neurons through in vivo electrophysiological recordings. RESULTS: In the absence of cues, sensitization promoted risk taking in both sexes. When rewards were cued, sensitization expedited the development of a risk-preferring phenotype in males while attenuating cue-induced risk taking in females. CONCLUSIONS: While these results provide further confirmation that ventral tegmental area DA neurons critically modulate risky decision making, they also reveal stark sex differences in the decisional impact that dopaminergic signals exert when winning outcomes are cued. As previously observed, risky decision making on the cued rat gambling task increased as both males and females learned to self-administer cocaine. The combination of DA sensitization and win-paired cues while gambling led to significantly greater cocaine taking, but these rats did not show any increase in risky choice as a result. Therefore, cocaine and heavily cued gambles may partially substitute for each other once the DA system has been rendered labile through sensitization, thereby compounding addiction risk across modalities.


Assuntos
Cocaína , Jogo de Azar , Humanos , Ratos , Masculino , Feminino , Animais , Sinais (Psicologia) , Neurônios Dopaminérgicos , Cocaína/farmacologia , Dopamina , Área Tegmentar Ventral , Tomada de Decisões/fisiologia
4.
Biol Trace Elem Res ; 202(4): 1477-1502, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37523058

RESUMO

Hypertension (HT) is a medical condition arising due to increase in blood pressure (BP) prevalent worldwide. The balanced dietary intakes of macro-elements and micro-elements including Na, K, Ca, Mg, Zn, and Cu have been described to maintain BP in humans by regulating the osmolarity of blood, cells/tissues, prevention of generation of oxidative and nitrosative stress (OANS), and endothelial damage through their functioning as important components of renin-angiotensin-aldosterone system (RAAS), antioxidant enzyme defense system, and maintenance of blood vascular-endothelial and vascular smooth muscle cell (VSMC) functions. However, inadequate/excess dietary intakes of Na/K, Ca/Mg, and Zn/Cu along with higher Pb and As exposures recognized to induce HT through common mechanisms including the followings: endothelial dysfunctions due to impairment of vasodilatation, increased vasoconstriction and arterial stiffness, blood clotting, inflammation, modification of sympathetic activity and higher catecholamine release, increased peripheral vascular resistance, and cardiac output; increased OANS due to reduced and elevated activities of extracellular superoxide dismutase and NAD(P)H oxidase, less nitric oxide bioavailability, decrease in cGMP and guanylate cyclase activity, increase in intracellular Ca2+ ions in VSMCs, and higher pro-inflammatory cytokines; higher parathyroid and calcitriol hormones; activation/suppression of RAAS resulting imbalance in blood Na+, K+, and water regulated by renin, angiotensin II, and aldosterone through affecting natriuresis/kaliuresis/diuresis; elevation in serum cholesterol and LDL cholesterol, decrease in HDL cholesterol due to defect in lipoprotein metabolism. The present study recommends the need to review simple dietary mineral intervention studies/supplementation trials before keeping their individual dietary excess intakes/exposures in consideration because their interactions lead to elevation and fall of their concentrations in body affecting onset of HT.


Assuntos
Hipertensão , Oligoelementos , Humanos , Chumbo , Oligoelementos/farmacologia , Sódio , Íons , Zinco
5.
J Ethnopharmacol ; 321: 117394, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37967777

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Plasmodium falciparum multi-drug resistant (MDR) strains are a great challenge to global health care. This predicament implies the urgent need to discover novel antimalarial drugs candidate from alternative natural sources. The Himalaya constitute a rich repository of medicinal plants which have been used traditionally in the folklore medicine since ages and having no scientific evidence for their activity. Crambe kotschyana Boiss. and Eremurus himalaicus Baker are used for their antipyretic and hepatoprotective properties in Kinnaur district of Himachal Pradesh, India. AIM OF THE STUDY: This study would investigate the antiplasmodial efficacy of C. kotschyana and E. himalaicus extracts, their fractions and active components using in vitro, in vivo and in silico approaches to provide a scientific insight into their activity. METHODS: The methanol extracts of C. kotschyana (CKME) and E. himalaicus (EHME) were prepared by maceration followed by fractionation using ethyl acetate. The isolation of flavonoid glycosides isorhamnetin-3, 7-di-O-glucoside from C. kotschyana and luteolin-6-C-glucoside (isoorientin) from E. himalaicus was carried out by antiplasmodial activity-guided isolation. In vitro antimalarial activity was assessed by WHO method while in vitro cytotoxicity was ascertained employing the MTT assay. Molecular docking and molecular dynamics simulation were performed using the Glide module of Schrödinger Software and Gromacs-2022 software package respectively. In vivo curative activity was assessed by Ryley and Peters method. RESULTS: The methanol extracts of both the plants illustrated the best antiplasmodial activity followed by the ethyl acetate fractions. Iso-orientin (IC50 6.49 µg/ml) and Isorhamnetin-3,7-di-O-glucoside (IC50 9.22 µg/ml) illustrated considerable in vitro activity even against P. falciparum resistant strain. Extracts/fractions as well as the isolated compounds were found to be non-toxic with CC50 > 640 µg/ml. Molecular docking studies were performed with these 2 O-glucosides against four malaria targets to understand the binding pose of these molecules and the results suggested that these molecules have selectivity for lactate dehydrogenase enzyme. CKME and EHME exhibited curative activity in vivo along with increase in Mean Survival Time of mice. CONCLUSION: The research delineated the scientific evidence that both the therapeutic herbs possessed antimalarial activity and notably, bioactive compounds responsible to exhibit the antimalarial activity have been isolated, identified and characterized. Further studies are underway to assess the antiplasmodial efficacy of isolated compounds alone and in combination with standard antimalarials.


Assuntos
Antimaláricos , Malária Falciparum , Malária , Parasitos , Animais , Camundongos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Antimaláricos/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/química , Metanol/uso terapêutico , Simulação de Acoplamento Molecular , Malária/tratamento farmacológico , Plasmodium falciparum , Malária Falciparum/tratamento farmacológico , Glucosídeos/uso terapêutico
6.
bioRxiv ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37808833

RESUMO

Extramedullary erythropoiesis is not expected in healthy adult mice, but erythropoietic gene expression was elevated in lineage-depleted spleen cells from cd47-/- mice. Expression of several genes associated with early stages of erythropoiesis was elevated in mice lacking CD47 or its signaling ligand thrombospondin-1, consistent with previous evidence that this signaling pathway inhibits expression of multipotent stem cell transcription factors in spleen. In contrast, cells expressing markers of committed erythroid progenitors were more abundant in cd47-/- spleens but significantly depleted in thbs1-/- spleens. Single cell transcriptome and flow cytometry analyses indicated that loss of CD47 is associated with accumulation and increased proliferation in spleen of Ter119-CD34+ progenitors and Ter119+CD34- committed erythroid progenitors with elevated mRNA expression of Kit, Ermap, and Tfrc. Induction of committed erythroid precursors is consistent with the known function of CD47 to limit the phagocytic removal of aged erythrocytes. Conversely, loss of thrombospondin-1 delays the turnover of aged red blood cells, which may account for the suppression of committed erythroid precursors in thbs1-/- spleens relative to basal levels in wild type mice. In addition to defining a role for CD47 to limit extramedullary erythropoiesis, these studies reveal a thrombospondin-1-dependent basal level of extramedullary erythropoiesis in adult mouse spleen.

7.
Semin Cell Dev Biol ; 155(Pt B): 22-31, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-37258315

RESUMO

Thrombospondin-1 is a secreted matricellular glycoprotein that modulates cell behavior by interacting with components of the extracellular matrix and with several cell surface receptors. Its presence in the extracellular matrix is induced by injuries that cause thrombospondin-1 release from platelets and conditions including hyperglycemia, ischemia, and aging that stimulate its expression by many cell types. Conversely, rapid receptor-mediated clearance of thrombospondin-1 from the extracellular space limits its sustained presence in the extracellular space and maintains sub-nanomolar physiological concentrations in blood plasma. Roles for thrombospondin-1 signaling, mediated by specific cellular receptors or by activation of latent TGFß, have been defined in T and B lymphocytes, natural killer cells, macrophages, neutrophils, and dendritic cells. In addition to regulating physiological nitric oxide signaling and responses of cells to stress, studies in mice lacking thrombospondin-1 or its receptors have revealed important roles for thrombospondin-1 in regulating immune responses in infectious and autoimmune diseases and antitumor immunity.


Assuntos
Antígeno CD47 , Transdução de Sinais , Animais , Camundongos , Antígeno CD47/metabolismo , Transdução de Sinais/fisiologia , Matriz Extracelular/metabolismo , Trombospondinas
8.
Molecules ; 28(12)2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37375374

RESUMO

Leishmaniasis is a neglected tropical disease, and there is an emerging need for the development of effective drugs to treat it. To identify novel compounds with antileishmanial properties, a novel series of functionalized spiro[indoline-3,2'-pyrrolidin]-2-one/spiro[indoline-3,3'-pyrrolizin]-2-one 23a-f, 24a-f, and 25a-g were prepared from natural-product-inspired pharmaceutically privileged bioactive sub-structures, i.e., isatins 20a-h, various substituted chalcones 21a-f, and 22a-c amino acids, via 1,3-dipolar cycloaddition reactions in MeOH at 80 °C using a microwave-assisted approach. Compared to traditional methods, microwave-assisted synthesis produces higher yields and better quality, and it takes less time. We report here the in vitro antileishmanial activity against Leishmania donovani and SAR studies. The analogues 24a, 24e, 24f, and 25d were found to be the most active compounds of the series and showed IC50 values of 2.43 µM, 0.96 µM, 1.62 µM, and 3.55 µM, respectively, compared to the standard reference drug Amphotericin B (IC50 = 0.060 µM). All compounds were assessed for Leishmania DNA topoisomerase type IB inhibition activity using the standard drug Camptothecin, and 24a, 24e, 24f, and 25d showed potential results. In order to further validate the experimental results and gain a deeper understanding of the binding manner of such compounds, molecular docking studies were also performed. The stereochemistry of the novel functionalized spirooxindole derivatives was confirmed by single-crystal X-ray crystallography studies.


Assuntos
Antiprotozoários , Leishmania donovani , Simulação de Acoplamento Molecular , Micro-Ondas , Antiprotozoários/química , Camptotecina/farmacologia , Relação Estrutura-Atividade
9.
Clin Chem Lab Med ; 61(7): 1280-1287, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37043622

RESUMO

OBJECTIVES: Monitoring quality indicators (QIs) is an important part of laboratory quality assurance (QA). Here, the Canadian Society of Clinical Chemists (CSCC) Point of Care Testing (POCT) and QI Special Interest Groups describe a process for establishing and monitoring QIs for POCT glucose testing. METHODS: Key, error prone steps in the POCT glucose testing process were collaboratively mapped out, followed by risk assessment for each step. Steps with the highest risk and ability to detect a non-conformance were chosen for follow-up. These were positive patient identification (PPID) and repeat of critically high glucose measurements. Participating sites were asked to submit aggregate data for these indicators from their site(s) for a one-month period. The PPID QI was also included as part of a national QI monitoring program for which fifty-seven sites submitted data. RESULTS: The percentage of POCT glucose tests performed without valid PPID ranged from 0-87%. Sites without Admission-Discharge-Transfer (ADT) connectivity to POCT meters were among those with the highest percentage of POCT glucose tests performed without valid PPID. The percentage repeated critically high glucose measurements ranged from 0-50%, indicating low compliance with this recommendation. A high rate of discordance was also noted when critically high POCT glucose measurements were repeated, demonstrating the importance of repeat testing prior to insulin administration. CONCLUSIONS: Here, a process for establishing these QIs is described, with preliminary data for two QIs chosen from this process. The findings demonstrate the importance of QIs for identification and comparative performance monitoring of non-conformances to improve POCT quality.


Assuntos
Glucose , Sistemas Automatizados de Assistência Junto ao Leito , Indicadores de Qualidade em Assistência à Saúde , Canadá , Opinião Pública , Glucose/química , Testes Imediatos , Humanos
10.
Int J Mol Sci ; 24(3)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36768931

RESUMO

Elevated expression of CD47 in some cancers is associated with poor survival related to its function as an innate immune checkpoint when expressed on tumor cells. In contrast, elevated CD47 expression in cutaneous melanomas is associated with improved survival. Previous studies implicated protective functions of CD47 expressed by immune cells in the melanoma tumor microenvironment. RNA sequencing analysis of responses induced by CD3 and CD28 engagement on wild type and CD47-deficient Jurkat T lymphoblast cells identified additional regulators of T cell function that were also CD47-dependent in mouse CD8 T cells. MYCN mRNA expression was upregulated in CD47-deficient cells but downregulated in CD47-deficient cells following activation. CD47 also regulated alternative splicing that produces two N-MYC isoforms. The CD47 ligand thrombospondin-1 inhibited expression of these MYCN mRNA isoforms, as well as induction of the oncogenic decoy MYCN opposite strand (MYCNOS) RNA during T cell activation. Analysis of mRNA expression data for melanomas in The Cancer Genome Atlas identified a significant coexpression of MYCN with CD47 and known regulators of CD8 T cell function. Thrombospondin-1 inhibited the induction of TIGIT, CD40LG, and MCL1 mRNAs following T cell activation in vitro. Increased mRNA expression of these T cell transcripts and MYCN in melanomas was associated with improved overall survival.


Assuntos
Antígeno CD47 , Melanoma , Camundongos , Animais , Antígeno CD47/metabolismo , Proteína Proto-Oncogênica N-Myc/genética , Linfócitos T CD8-Positivos , Expressão Gênica , Melanoma/genética , RNA Mensageiro/genética , Trombospondinas/genética , Microambiente Tumoral
11.
J Neurosci ; 43(6): 979-992, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36623876

RESUMO

Impulse control and/or gambling disorders can be triggered by dopamine agonist therapies used to treat Parkinson's disease, but the cognitive and neurobiological mechanisms underlying these adverse effects are unknown. Recent data show that adding win-paired sound and light cues to the rat gambling task (rGT) potentiates risky decision-making and impulsivity via the dopamine system, and that changing dopaminergic tone has a greater influence on behavior while subjects are learning task contingencies. Dopamine agonist therapy may therefore be potentiating risk-taking by amplifying the behavioral impact of gambling-related cues on novel behavior. Here, we show that ropinirole treatment in male rats transiently increased motor impulsivity but robustly and progressively increased choice of the high-risk/high-reward options when administered during acquisition of the cued but not uncued rGT. Early in training, ropinirole increased win-stay behavior after large unlikely wins on the cued rGT, indicative of enhanced model-free learning, which mediated the drug's effect on later risk preference. Ex vivo cFos imaging showed that both chronic ropinirole and the addition of win-paired cues suppressed the activity of dopaminergic midbrain neurons. The ratio of midbrain:prefrontal cFos+ neurons was lower in animals with suboptimal choice patterns and tended to predict risk preference across all rats. Network analyses further suggested that ropinirole induced decoupling of the dopaminergic cells of the VTA and nucleus accumbens but only when win-paired cues were present. Frontostriatal activity uninformed by the endogenous dopaminergic teaching signal therefore appeared to perpetuate risky choice, and ropinirole exaggerated this disconnect in synergy with reward-paired cues.SIGNIFICANCE STATEMENT D2/3 receptor agonists, used to treat Parkinson's disease, can cause gambling disorder through an unknown mechanism. Ropinirole increased risky decision-making in rats, but only when wins were paired with casino-inspired sounds and lights. This was mediated by increased win-stay behavior after large unlikely wins early in learning, indicating enhanced model-free learning. cFos imaging showed that ropinirole suppressed activity of midbrain dopamine neurons, an effect that was mimicked by the addition of win-paired cues. The degree of risky choice rats exhibited was uniquely predicted by the ratio of midbrain dopamine:PFC activity. Depriving the PFC of the endogenous dopaminergic teaching signal may therefore drive risky decision-making on-task, and ropinirole acts synergistically with win-paired cues to amplify this.


Assuntos
Agonistas de Dopamina , Doença de Parkinson , Ratos , Masculino , Animais , Agonistas de Dopamina/farmacologia , Dopamina/farmacologia , Sinais (Psicologia) , Ratos Long-Evans , Recompensa , Comportamento de Escolha/fisiologia , Tomada de Decisões/fisiologia
12.
J Cell Commun Signal ; 17(3): 485-493, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36689135

RESUMO

Matricellular proteins comprise several families of secreted proteins that function in higher animals at the interface between cells and their surrounding extracellular matrix. Targeted gene disruptions that result in loss of viability in mice have revealed critical roles for several matricellular proteins in murine embryonic development, including two members of the cellular communication network (CCN) gene family. In contrast, mice lacking single or multiple members of the thrombospondin (THBS) gene family remain viable and fertile. The frequency of loss of function mutants, identified using human deep exome sequencing data, provided evidence that some of the essential genes in mice, including Ccn1, are also essential genes in humans. However, a deficit in loss of function mutants in humans indicated that THBS1 is also highly loss-intolerant. In addition to roles in embryonic development or adult reproduction, genes may be loss-intolerant in humans because their function is needed to survive environmental stresses that are encountered between birth and reproduction. Laboratory mice live in a protected environment that lacks the exposures to pathogens and injury that humans routinely face. However, subjecting Thbs1-/- mice to defined stresses has provided valuable insights into functions of thrombospondin-1 that could account for the loss-intolerance of THBS1 in humans. Stress response models using transgenic mice have identified protective functions of thrombospondin-1 in the cardiovascular system (red) and immune defenses (blue) that could account for its intolerance to loss of function mutants in humans.

13.
Mini Rev Med Chem ; 23(8): 898-916, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36545713

RESUMO

One of the most fatal infectious diseases, malaria, still poses a threat to about half of the world's population and is the leading cause of death worldwide. The use of artemisinin-based combination therapy has helped to significantly reduce the number of deaths caused by malaria, but the emergence of drug resistance threatens to undo this gain. In a bid to boost adherence, several new combination therapies with effectiveness against drug-resistant parasites are currently being tested in clinical settings. Nevertheless, notwithstanding these gains, malaria must be completely eradicated by a concerted international effort on several fronts. Quinoline-based compounds were the cornerstone of malaria chemotherapy until recently when resistance to these drugs severely hampered efforts to achieve a "Zero Malaria" world. The inappropriate use of available antimalarials is one of the factors responsible for resistance development and treatment failure, warranting the search for new chemical entities and alternative approaches to combat this threat. A vast number of solutions have emerged and one of them, quinoline-hybridization, is an effective method for introducing structural diversity, resulting in molecules with improved biological activities, reduced drug resistance, fewer drug-drug interactions, and improved safety and pharmacokinetic profiles. Choosing the ideal target combination and achieving a balanced activity toward them while preserving drug-like properties are the key challenges in the development of molecular hybrids. This review examines the highlights of quinoline hybridization, with some of the hybrids exhibiting remarkable in vitro and in vivo activities, emphasizing that it is a useful method for developing new anti-malarial lead compounds.


Assuntos
Antimaláricos , Malária Falciparum , Malária , Quinolinas , Humanos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Antimaláricos/química , Malária/tratamento farmacológico , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Resistência a Medicamentos , Terapia Combinada , Plasmodium falciparum , Malária Falciparum/tratamento farmacológico
14.
Phytochemistry ; 206: 113525, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36442578

RESUMO

Naturally occurring pentacyclic triterpenoids and their semisynthetic analogues have engrossed increasing attention for their anticancer potential and exhibiting promising role in discovery of new anticancer agents. Present study include the semi synthetic modifications of Lantadenes from the weed Lantana carama and their structures delineation by FT-IR, 1H-NMR, 13C-NMR & mass spectroscopy. All the compounds were scrutinized for in vitro cytotoxicity, ligand receptor interaction and in vivo anticancer studies. Most of the novel analogues displayed potent antiproliferative activity against A375 & A431 cancer cell lines and found superior to parent Lantadenes. In particular, 3ß-(4-Methoxybenzoyloxy)-22ß-senecioyloxy-olean-12-en-28-oic acid was found to be most suitable compound, with IC50 value of 3.027 µM aganist A375 cell line having least docking score (-69.40 kcal/mol). Promising anticancer potential of the lead was further indicated by significant reduction in tumor volume and burden in two stage carcinoma model. These findings suggests that the Lantadene derivatives may hold promising potential for the intervention of skin cancers.


Assuntos
Antineoplásicos , Lantana , Lantana/química , Espectroscopia de Infravermelho com Transformada de Fourier , Triterpenos Pentacíclicos , Linhagem Celular , Antineoplásicos/farmacologia
15.
Mol Pharm ; 20(1): 118-127, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36384279

RESUMO

Artemether oily injection is recommended for the treatment of severe malaria by the intramuscular route. The major limitations of the artemisinin combination therapy are erratic absorption from the injection site and high dosing frequency due to a very short elimination half-life of the drug. Advanced drug delivery systems have shown significant improvement in the current malaria therapy; the desired drug concentration within infected erythrocytes is yet the major challenge. Recently, we have reported the fabrication of artemether-loaded polymeric nanorods for intravenous malaria therapy which was found to be biocompatible with THP-1 monocytes and rat erythrocytes. The objective of the present study was the evaluation of pharmacokinetics, biodistribution, and antimalarial efficacy of artemether-loaded polymeric nanorods. Scanning electron microscopy and confocal microscopy studies revealed that both nanospheres and nanorods were adsorbed onto the surface of rat erythrocytes after an incubation of 10 min. After intravenous administration to rats, artemether nanorods showed higher plasma concentration and lower elimination rate of artemether when compared with nanospheres. The biodistribution studies showed that, at 30 min, the liver concentration of DiR-loaded nanospheres was higher than that of DiR-loaded nanorods after intravenous administration to BALB/c mice. The in vitro schizont inhibition study showed that both nanorods and nanospheres exhibited concentration-dependent parasitic inhibition, wherein at lower concentrations (2 ppm), nanorods were more effective than nanospheres. However, at higher concentrations, nanospheres were found to be more effective. Nanorods showed higher chemosuppression on day 5 and day 7 than nanospheres and free artemether when studied with the Plasmodium berghei mouse model. Moreover, the survival rate of P. berghei infected mice was also found to be higher after treatment with artemether nanoformulations when compared with free artemether. In conclusion, polymeric nanorods could be a promising next-generation delivery system for the treatment of malaria.


Assuntos
Antimaláricos , Malária , Nanotubos , Camundongos , Ratos , Animais , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Artemeter/uso terapêutico , Distribuição Tecidual , Malária/tratamento farmacológico , Malária/parasitologia
16.
Behav Neurosci ; 137(1): 41-51, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36395021

RESUMO

The main psychoactive compound within the cannabis plant, Δ9-tetrahydrocannabinol (THC), is thought to drive both the sensation of "high" and the cognitive impairments associated with cannabis consumption. Researchers keen to understand how cannabis impairs cognition have, therefore, studied the behavioral effects of systemic injections of THC in animal models. However, cannabis contains multiple other cannabinoids which may critically modulate the resulting cognitive effects. Users also typically eat or smoke cannabis, leading to concern over the translational validity of pure THC injections. We, therefore, tested whether acute oral administration of two different commercially available cannabis extracts, marketed as C. indica or C. sativa, decreased male Long-Evans rats' willingness to exert greater cognitive effort in order to maximize reward earned, as expected from previous experiments using injected THC. Both oils were matched for THC and cannabidiol content. While both cannabis products slowed response times at higher doses, only C. indica oil at the highest dose administered (10 mg/kg THC) decreased the number of trials on which rats chose to complete high-effort/high-reward trials. Repeated dosing with a medium dose of either cannabinoid product (3 mg/kg THC) did not influence choice. Ex vivo analyses confirmed comparable levels of brain THC after C. indica or C. sativa administration. Although controversial in the field, these results support the suggestion that products marketed as different cannabis cultivars have dissociable cognitive effects that may not resemble pure THC and emphasize the importance of the route of administration in experimental design. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Canabidiol , Cannabis , Ratos , Animais , Dronabinol/farmacologia , Esforço Físico , Ratos Long-Evans , Canabidiol/farmacologia , Cognição
17.
Med Microbiol Immunol ; 212(1): 35-51, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36399160

RESUMO

Parasite of genus Leishmania viz. L. donovani and L. infantum cause visceral leishmaniasis (VL) or Kala-azar, systemic disease with significant enlargement of the liver and spleen, weight loss, anemia, fever and immunosuppression. The silent expansion of vectors, reservoir hosts and resistant strains is also of great concern in VL control. Considering all these issues, the present study focused on in vitro and in vivo antileishmanial screening of ellagic acid (EA) against L. donovani. The in vitro study was performed against the protozoan parasite L. donovani and a 50% inhibitory concentration was calculated. The DNA arrest in the sub-G0/G1 phase of the cell cycle was studied. In vivo studies included the assessment of parasite burden and immunomodulation in response to treatment of ellagic acid in BALB/c mice. The levels of Th1 and Th2 cytokines and isotype antibodies were assessed in different groups of mice. EA showed in vitro parasiticidal activity with IC50 18.55 µg/mL and thwarted cell-cycle progression at the sub-G0/G1 phase. Administration of ellagic acid to the BALB/c mice reported diminution of splenic and hepatic parasite burden coupled with an expansion of CD4+ and CD8+ T lymphocytes. EA further potentiated a protective immune response with augmentation of Th1 type immune response evidenced by elevation of serum IgG2a levels and DTH response. EA was reported to be safe and non-toxic to the THP-1 cell line as well as to the liver and kidneys of mice. These findings endorse the therapeutic potential of EA with significant immunomodulation and can serve as a promising agent against this debilitating parasitic disease.


Assuntos
Antiprotozoários , Leishmania donovani , Leishmaniose Visceral , Animais , Camundongos , Leishmania donovani/fisiologia , Ácido Elágico/farmacologia , Ácido Elágico/uso terapêutico , Modelos Animais de Doenças , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Camundongos Endogâmicos BALB C
18.
J Vector Borne Dis ; 60(4): 439-443, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38174524

RESUMO

Background & objectives: The affirmation about the prevalence of mosquito species at a particular place and time is very significant, not only to predict the danger of diseases or future outbreaks but also to control the vectors in time. Despite mosquitoes being medically important, the information about its faunal diversity is very scanty as far as Chandigarh in India and its nearby areas are concerned. So, this study was carried out to survey the mosquito fauna from areas in and around Chandigarh in northern India. Methods: Detailed mosquito surveys were carried out to explore the mosquito fauna from various habitats of developed urban areas, gardens, slums and surrounding villages of Chandigarh from June 2017-November 2019 using hand nets and oral aspirators. Results: A total of 34 mosquito species belonging to 8 genera viz; Anopheles, Aedes, Armigeres, Culex, Coquillet-tidia, Mansonia, Mimomyia and Verrallina were recorded, identified and preserved along with detailed collection data, of which eight are new records from Chandigarh. Interpretation & conclusion: The present checklist of mosquito fauna comprising 34 species provides information on the occurrence of mosquito vectors in Chandigarh and its adjoining areas which will be beneficial for the health authorities to adopt appropriate measures in time for the control of these vectors.


Assuntos
Aedes , Anopheles , Culex , Culicidae , Animais , Lista de Checagem , Índia , Mosquitos Vetores
20.
Oncoimmunology ; 11(1): 2111909, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36105746

RESUMO

CD47 has established roles in the immune system for regulating macrophage phagocytosis and lymphocyte activation, with growing evidence of its cell-intrinsic regulatory roles in natural killer and CD8+ T cells. CD47 limits antigen-dependent cytotoxic activities of human and murine CD8+ T cells, but its role in T cell activation kinetics remains unclear. Using in vitro and in vivo models, we show here that CD47 differentially regulates CD8+ T cell responses to short- versus long-term activation. Although CD47 was not required for T cell development in mice and early activation in vitro, short-term stimuli elevated pathogen-reactive gene expression and enhanced proliferation and the effector phenotypes of Cd47-deficient relative to Cd47-sufficient CD8+ T cells. In contrast, persistent TCR stimulation limited the effector phenotypes of Cd47 -/- CD8+ T cells and enhanced their apoptosis signature. CD8+ T cell expansion and activation in vivo induced by acute lymphocytic choriomeningitis virus (LCMV) infection did not differ in the absence of CD47. However, the frequency and effector phenotypes of Cd47-/- CD8+ T cells were constrained in chronic LCMV-infected as well as in mice bearing B16 melanoma tumors. Therefore, CD47 regulates CD8+ T cell activation, proliferation, and fitness in a context-dependent manner.


Assuntos
Ativação Linfocitária , Coriomeningite Linfocítica , Animais , Antígeno CD47/genética , Linfócitos T CD8-Positivos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
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