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1.
Curr Microbiol ; 81(8): 245, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940852

RESUMO

Garlic (Allium sativum L.), particularly its volatile essential oil, is widely recognized for medicinal properties. We have evaluated the efficacy of Indian Garlic Essential Oil (GEO) for antimicrobial and antibiofilm activity and its bioactive constituents. Allyl sulfur-rich compounds were identified as predominant phytochemicals in GEO, constituting 96.51% of total volatile oils, with 38% Diallyl trisulphide (DTS) as most abundant. GEO exhibited significant antibacterial activity against eleven bacteria, including three drug-resistant strains with minimum inhibitory concentrations (MICs) ranging from 78 to 1250 µg/mL. In bacterial growth kinetic assay GEO effectively inhibited growth of all tested strains at its ½ MIC. Antibiofilm activity was evident against two important human pathogens, S. aureus and P. aeruginosa. Mechanistic studies demonstrated that GEO disrupts bacterial cell membranes, leading to the release of nucleic acids, proteins, and reactive oxygen species. Additionally, GEO demonstrated potent antioxidant activity at IC50 31.18 mg/mL, while its isolated constituents, Diallyl disulphide (DDS) and Diallyl trisulphide (DTS), showed effective antibacterial activity ranging from 125 to 500 µg/mL and 250-1000 µg/mL respectively. Overall, GEO displayed promising antimicrobial and antibiofilm activity against enteric bacteria, suggesting its potential application in the food industry.


Assuntos
Antibacterianos , Antioxidantes , Biofilmes , Alho , Testes de Sensibilidade Microbiana , Óleos Voláteis , Alho/química , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Antioxidantes/farmacologia , Antioxidantes/química , Antibacterianos/farmacologia , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia , Compostos Alílicos/farmacologia , Compostos Alílicos/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/química , Sulfetos/farmacologia , Bactérias/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Dissulfetos/farmacologia , Índia , Óleos de Plantas/farmacologia , Óleos de Plantas/química , Humanos , Extratos Vegetais/farmacologia , Extratos Vegetais/química
2.
Cytokine ; 154: 155871, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35436657

RESUMO

Elicitation of the tumor-eliminating immune response is a major challenge, as macrophages- constituting a major component of solid tumor mass- play important roles in development, maintenance and tumor regression. The macrophage-expressed Toll-Like Receptors (TLRs) enhance macrophage function and their ability to activate T cells via secretion of cytokines, which may help in tumor regression. IL-27, a member of the IL-12 family of cytokines, is shown to exhibit anti-tumor and anti-angiogenic activities. Herein, we developed B16BL6 melanoma model in C75BL/6 mouse to dissect the crosstalk between TLRs and IL-27 in tumors. We report existence of a novel TLR- IL-27 feed-forward loop, whereby TLRs and IL-27 up-regulated each other's expression, which we found perturbed during melanoma tumorigenesis. Intra-tumoral injection of Imiquimod, a TLR7/8 ligand, reduced the tumor burden; the anti-tumor effect was reversed upon IL-27 and IL-27R silencing by intra-tumorally administered, lentivirally expressed IL-27 and IL-27R shRNA. The reduced tumor growth was accompanied by significantly fewer Treg cells but increased IFN-γ and granzyme B expression by CD8+ T cells. These data indicate the preventative role for TLR-induced IL-27 in aggressive and highly invasive melanoma.


Assuntos
Interleucina-27 , Melanoma Experimental , Receptores Toll-Like , Animais , Linfócitos T CD8-Positivos/metabolismo , Citocinas/metabolismo , Interleucina-27/metabolismo , Interleucinas , Melanoma Experimental/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Receptores Toll-Like/metabolismo
3.
Malar J ; 21(1): 32, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35109868

RESUMO

BACKGROUND: Regulatory T cells are known to play a key role to counter balance the protective immune response and immune mediated pathology. However, the role of naturally occurring regulatory cells CD4+CD25+Foxp3+ in malaria infection during the disease pathogenesis is controversial. Beside this, ICOS molecule has been shown to be involved in the development and function of regulatory T cell enhance IL-10 production. Therefore, possible involvement of the ICOS dependent regulatory CD4+ICOS+Foxp3+ T cells in resistance/susceptibility during malaria parasite is explored in this study. METHODS: 5 × 105 red blood cells infected with non-lethal and lethal parasites were inoculated in female Balb/c mice by intra-peritoneal injection. Infected or uninfected mice were sacrificed at early (3rd day post infection) and later stage (10th day post infection) of infection. Harvested cells were analysed by using flow cytometer and serum cytokine by Bioplex assay. RESULTS: Thin blood films show that percentages of parasitaemia increases with disease progression in infections with the lethal malaria parasite and mice eventually die by day 14th post-infection. Whereas in case of non-lethal malaria parasite, parasitaemia goes down by 7th day post infection and gets cleared within 13th day. The number of CD4+ ICOS+ T cells increases in lethal infection with disease progression. Surprisingly, in non-lethal parasite, ICOS expression decreases after day 7th post infection as parasitaemia goes down. The frequency of CD4+ICOS+FoxP3+ Tregs was significantly higher in lethal parasitic infection as compared to the non-lethal parasite. The level of IL-12 cytokine was remarkably higher in non-lethal infection compared to the lethal infection. In contrast, the level of IL-10 cytokines was higher in lethal parasite infection compared to the non-lethal parasite. CONCLUSION: Taken together, these data suggest that lethal parasite induce immunosuppressive environment, protecting from host immune responses and help the parasite to survive whereas non-lethal parasite leads to low frequencies of Treg cells seldom impede immune response that allow the parasite to get self-resolved.


Assuntos
Malária/etiologia , Linfócitos T Reguladores/fisiologia , Animais , Antígenos CD4/fisiologia , Citocinas/análise , Feminino , Citometria de Fluxo , Fatores de Transcrição Forkhead/fisiologia , Humanos , Proteína Coestimuladora de Linfócitos T Induzíveis/fisiologia , Interleucina-10/análise , Malária/diagnóstico , Malária/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Parasitemia/diagnóstico , Parasitemia/parasitologia , Fragmentos de Peptídeos/fisiologia , Plasmodium berghei , Plasmodium chabaudi , Plasmodium yoelii , Organismos Livres de Patógenos Específicos , Baço/citologia
4.
Arch Virol ; 166(8): 2187-2198, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34041610

RESUMO

Stephania hernandifolia (Nimukho), an ethnomedicinal herb from rural Bengal, has been used traditionally for the management of nerve, skin, urinary, and digestive ailments. Here, we attempted to confirm the antiviral potential of aqueous, methanol, and chloroform extracts of S. hernandifolia against herpes simplex virus type 1 (HSV-1), the causative agent of orolabial herpes in humans, and decipher its underlying mechanism of action. The bioactive extract was standardized and characterized by gas chromatography-mass spectroscopy, while cytotoxicity and antiviral activity were evaluated by MTT and plaque reduction assay, respectively. Two HSV strains, HSV-1F and the clinical isolate VU-09, were inhibited by the chloroform extract (CE) with a median effective concentration (EC50) of 4.32 and 4.50 µg/ml respectively, with a selectivity index (SI) of 11. Time-of-addition assays showed that pre-treatment of virus-infected cells with the CE and its removal before infection reduced the number of plaques without lasting toxicity to the cell, indicating that the CE affected the early stage in the viral life cycle. The number of plaques was also reduced by direct inactivation of virions and by the addition of CE for a short time following attachment of virions. These results together suggest that modification of either the virion surface or the cell surface by the CE inhibits virus entry into the host cell.


Assuntos
Herpes Simples/virologia , Herpesvirus Humano 1/fisiologia , Extratos Vegetais/farmacologia , Stephania/química , Animais , Chlorocebus aethiops , Clorofórmio/química , Cromatografia Gasosa-Espectrometria de Massas , Herpes Simples/tratamento farmacológico , Herpesvirus Humano 1/efeitos dos fármacos , Medicina Tradicional , Metanol/química , Modelos Biológicos , Extratos Vegetais/química , Células Vero , Ativação Viral/efeitos dos fármacos , Internalização do Vírus/efeitos dos fármacos
5.
Phytother Res ; 35(8): 4246-4257, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33817867

RESUMO

Coronavirus disease 2019 (COVID-19) triggered by a new viral pathogen, named severe acute respiratory syndrome Coronavirus-2 (SARS-CoV-2), is now a global health emergency. This debilitating viral pandemic not only paralyzed the normal daily life of the global community but also spread rapidly via global travel. To date there are no effective vaccines or specific treatments against this highly contagious virus; therefore, there is an urgent need to advocate novel prophylactic or therapeutic interventions for COVID-19. This brief opinion critically discusses the potential of Silymarin, a flavonolignan with diverse pharmacological activity having antiinflammatory, antioxidant, antiplatelet, and antiviral properties, with versatile immune-cytokine regulatory functions, that able to bind with transmembrane protease serine 2 (TMPRSS2) and induce endogenous antiviral cytokine interferon-stimulated gene 15, for the management of COVID-19. Silymarin inhibits the expression of host cell surface receptor TMPRSS2 with a docking binding energy corresponding to -1,350.61 kcal/mol and a full fitness score of -8.11. The binding affinity of silymarin with an impressive virtual score exhibits significant potential to interfere with SARS-CoV-2 replication. We propose in-depth pre-clinical and clinical review studies of silymarin for the development of anti-COVID-19 lead, based on its clinical manifestations of COVID-19 and multifaceted bioactivities.


Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , COVID-19 , Silimarina , Antivirais/farmacologia , Antivirais/uso terapêutico , COVID-19/prevenção & controle , Humanos , Pandemias , SARS-CoV-2/efeitos dos fármacos , Silimarina/farmacologia , Silimarina/uso terapêutico
6.
Rev Argent Microbiol ; 53(4): 281-286, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33608109

RESUMO

Increasing antimicrobial resistance among Staphylococcus aureus necessitates a new antimicrobial with a different site of action. We have isolated a novel cyclic peptide-1 (ASP-1) from Bacillussubtilis with potent activity against methicillin-resistant S. aureus (MRSA) at a minimum inhibitory concentration (MIC) of 8-64µg/ml. Scanning electron micrographs demonstrated drastic changes in the cellular architecture of ASP-1 treated cells of S. aureus ATCC 29213 and an MRSA clinical isolate at MICs, with damages to the cell wall, membrane lysis and probable leakage of cytoplasmic contents at minimum bactericidal concentrations. The ultrastructure alterations induced by ASP-1 have also been compared with those of oxacillin-treated MRSA cells at its MIC using scanning electron microscopy.


Assuntos
Antibacterianos , Staphylococcus aureus Resistente à Meticilina , Peptídeos Cíclicos/farmacologia , Antibacterianos/farmacologia , Bacillus subtilis/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/ultraestrutura , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura
7.
J Biol Chem ; 294(21): 8555-8563, 2019 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-30975902

RESUMO

The widespread availability and use of modern synthetic therapeutic agents have led to a massive decline in ethnomedical therapies. However, these synthetic agents often possess toxicity leading to various adverse effects. For instance, anti-tubercular treatment (ATT) is toxic, lengthy, and severely impairs host immunity, resulting in posttreatment vulnerability to reinfection and reactivation of tuberculosis (TB). Incomplete ATT enhances the risk for the generation of multidrug- or extensively drug-resistant (MDR or XDR, respectively) variants of Mycobacterium tuberculosis (M. tb), the TB-causing microbe. Therefore, a new therapeutic approach that minimizes these risks is urgently needed to combat this deadly disease and prevent future TB epidemics. Previously, we have shown that the phytochemical bergenin induces T helper 1 (Th1)- and Th17 cell-based protective immune responses and potently inhibits mycobacterial growth in a murine model of M. tb infection, suggesting bergenin as a potential adjunct agent to TB therapy. Here, we combined ATT therapy with bergenin and found that this combination reduces immune impairment and the length of treatment in mice. We observed that co-treatment with the anti-TB drug isoniazid and bergenin produces additive effects and significantly reduces bacterial loads compared with isoniazid treatment alone. The bergenin co-treatment also reduced isoniazid-induced immune impairment; promoted long-lasting, antigen-specific central memory T cell responses; and acted as a self-propelled vaccine. Of note, bergenin treatment significantly reduced the bacterial burden of a multidrug-resistant TB strain. These observations suggest that bergenin is a potent immunomodulatory agent that could be further explored as a potential adjunct to TB therapy.


Assuntos
Benzopiranos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Imunoterapia , Isoniazida/farmacologia , Mycobacterium tuberculosis/imunologia , Células Th1/imunologia , Células Th17/imunologia , Tuberculose Resistente a Múltiplos Medicamentos , Animais , Farmacorresistência Bacteriana Múltipla/imunologia , Camundongos , Células Th1/patologia , Células Th17/patologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/imunologia , Tuberculose Resistente a Múltiplos Medicamentos/patologia
8.
Microb Pathog ; 137: 103714, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31493502

RESUMO

Leprosy, once considered as poor man's disease may cause severe neurological complications and physical disabilities. Classification of leprosy depends upon the cell mediated and humoral immune responses of the host, from tuberculoid to lepromatous stage. Current therapy to prevent the disease is not only very lengthy but also consists of expensive multiple antibiotics in combination. Treatment and the duration depend on the bacillary loads, from six months in paucibacillary to a year in multibacillary leprosy. Although as per WHO recommendations, these antibiotics are freely available but still out of reach to patients of many rural areas of the world. In this review, we have focused on the nutritional aspect during the multi-drug therapy of leprosy along with the role of nutrition, particularly malnutrition, on susceptibility of Mycobacterium leprae and development of clinical symptoms. We further discussed the diet plan for the patients and how diet plans can affect the immune responses during the disease.


Assuntos
Dieta , Hanseníase/tratamento farmacológico , Hanseníase/imunologia , Desnutrição , Antígenos de Bactérias/farmacologia , Citocinas/metabolismo , Alimentos , Predisposição Genética para Doença , Humanos , Imunidade , Imunidade Humoral , Hanseníase/diagnóstico , Hanseníase/metabolismo , Masculino , Mycobacterium leprae/imunologia , Estado Nutricional , Fatores de Risco , Selênio , Vitaminas , Zinco
9.
Arch Virol ; 164(5): 1433-1439, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30868265

RESUMO

Herpes simplex virus 1 (HSV-1), a double-stranded DNA virus, infects epithelial surfaces and establishes latency in the central nervous system, where astrocytes are a major immune cell type. Here, we report changes that occur in the expression of pathogen recognition receptors, such as Toll-like receptors, DNA and RNA sensors, interferons, and interferon-stimulated genes, when astrocytes are infected with HSV-1 strain F. We observed upregulation of Toll-like receptors 2, 6 and 9, MDA5, and DAI along with an increase in the expression of type I interferons and interferon-stimulated genes such as IFIT1, IFIT3 and RNase L. These genes encode proteins that mediate the antiviral immune response.


Assuntos
Astrócitos/imunologia , Astrócitos/virologia , Herpesvirus Humano 1/imunologia , Imunidade Inata/imunologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Proteínas de Transporte/metabolismo , Chlorocebus aethiops , Endorribonucleases/metabolismo , Helicase IFIH1 Induzida por Interferon/biossíntese , Peptídeos e Proteínas de Sinalização Intracelular , Camundongos , Proteínas/metabolismo , Proteínas de Ligação a RNA , Receptor 2 Toll-Like/biossíntese , Receptor 6 Toll-Like/biossíntese , Receptor Toll-Like 9/biossíntese , Regulação para Cima/genética , Células Vero , Replicação Viral , eIF-2 Quinase/biossíntese
10.
Cytokine ; 112: 52-62, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29960669

RESUMO

Recent evidences indicate that change in cellular metabolic pathways can alter immune response and function of the host; emphasizing the role of metabolome in health and diseases. Human Herpes simplex virus type-1 (HSV-1) and type-2 (HSV-2) causes diseases from asymptomatic to highly prevalent oral and genital herpes, recurrent blisters or neurological complications. Immune responses against HSV are complex with delicate interplay between innate signaling pathways and adaptive immune responses. The innate response involves the induction of protective IFN-1; while Natural Killer (NK) cells and plasmacytoid Dendritic Cells (pDC) confer in vivo adaptive anti-HSV response along with humoral and cellular components in controlling infection and latency. Metabolic changes lead to up-/down-regulation of several cytokines and chemokines like IFN-γ, IL-2, IL-4, IL-10 and MIP1ß in HSV infection and recurrences. Recently, the viral protein ICP0 has been identified as an attenuator of TLR signaling, that inhibit innate responses to HSV. This review will summarize the role of metabolome in innate and adaptive effectors in infection, pathogenesis and immune control of HSV, highlighting the delicate interplay between the metabolic changes and immunity.


Assuntos
Herpes Simples/imunologia , Herpes Simples/metabolismo , Simplexvirus/imunologia , Imunidade Adaptativa/imunologia , Animais , Citocinas/imunologia , Citocinas/metabolismo , Humanos , Imunidade Inata/imunologia , Células Matadoras Naturais/imunologia , Metaboloma/imunologia , Transdução de Sinais/imunologia
11.
Cytokine ; 104: 114-123, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29032985

RESUMO

Random mutations leading to loss of cell cycle control is not a rare occurrence in an organism but the mutated cells are recognized and eliminated preventing the development of a tumor. These potentially tumorigenic cells release damage-associated molecular patterns (DAMPs), which are recognized by toll-like receptors (TLRs) on macrophages and dendritic cells. The initial TLR-DAMP interactions lead to different responses such as altered antigen presentation and cytokine release that directly affect T cell activation and removal of the tumorigenic cells. The indirect effects of TLR-DAMP interaction include chemokine-directed altered T cell trafficking, angiogenesis for both T cell infiltration and tumor cell metastasis, and alteration of intra-tumoral milieu contributing to the development of tumor cells heterogeneity. Thus, the initial TLR-DAMP interaction has a set of local effects that modulate tumor cell growth and heterogeneity and a disseminating set of central effects that dynamically affect T cell trafficking and functions. Herein, we argue that the DAMP-TLR-cytokine axis in the tumor microenvironment serves as the mainstay that orchestrates and regulates the pro- and anti-tumor elements which dynamically interact between themselves eventuating in tumor regression or growth. The knowledge of this TLR-based immuno-surveillance framework is a key to developing a novel immunotherapy against cancer.


Assuntos
Citocinas/metabolismo , Neoplasias/metabolismo , Moléculas com Motivos Associados a Patógenos/metabolismo , Transdução de Sinais , Receptores Toll-Like/metabolismo , Animais , Humanos , Neoplasias/imunologia , Neoplasias/patologia , Microambiente Tumoral
12.
Cytokine ; 112: 12-15, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29885992

RESUMO

Leishmania donovani is a protozoan parasite that infects mammalian macrophages, wherein the parasite resides and replicates as amastigotes, inflicting the potentially fatal disease visceral leishmaniasis. The disease is characterized by severe immunosuppression and hypocholesterolemia implying metabolic changes in L. donovani infection; whether such metabolic changes are also linked to susceptibility to the infection is not known. Herein, four inbred mouse strains were first characterized for their resistance or susceptibility profile to L. donovani infection. It was observed that these four mouse strains were differentially susceptible to L. donovani infection. Splenic expression of four key cytokines- IL-10, IL-12, IFN-γ and IL-4- revealed that the differential susceptibility of these four mouse strains to L. donovani was partially associated with these cytokines. The association was further correlated with the expression of different enzymes of the glycolytic pathway in the spleen of these L. donovani-infected mice. Thus, the observations reported here suggest an association between host metabolism, cytokine secretion profile and L. donovani susceptibility. As the chemotherapeutic choices are extremely limited and a vaccine for human use is yet to be discovered for the neglected tropical disease that is prevalent in 88 countries affecting 320 million people, this metabolic study is a significant research area that has potentials to develop a new target for anti-leishmanial chemotherapy.


Assuntos
Leishmania donovani/imunologia , Leishmaniose Visceral/imunologia , Leishmaniose Visceral/metabolismo , Animais , Citocinas/imunologia , Citocinas/metabolismo , Leishmaniose Visceral/parasitologia , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Baço/imunologia , Baço/metabolismo , Baço/parasitologia
13.
Cytokine ; 104: 110-113, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29017773

RESUMO

Toll-like receptors (TLRs) recognize the pathogen-associated molecular patterns (PAMPs) and induce host-protective immune response. The role of the profilin-recognizing TLR11/TLR12 in Leishmania infection is unknown. Herein, we report that TLR11/ TLR12 expression increases in virulent L. major-infected macrophages but is prevented by miltefosine, an anti-leishmanial drug. While lipohosphoglycan (LPG) increases, LPG or TLR2 blockade prevents, the heightened TLR11/TLR12 expression. LPG-TLR2 interaction triggers MyD88- and TIRAP-mediated signaling enhancing ERK-1/2 activation and increased production of IL-10 that promotes TLR11/TLR12 expression. Profilin expression was higher in the virulent L. major and L. donovani parasites than that observed in the avirulent parasites. TLR11 or TLR12 silencing reduces parasite burden and increases IFN-γ, but reduces IL-4, production indicating that TLR11 and TLR12 play a pro-leishmanial role.


Assuntos
Inativação Gênica , Leishmania major/fisiologia , Leishmaniose/metabolismo , Receptores Toll-Like/metabolismo , Animais , Macrófagos/metabolismo , Camundongos Endogâmicos BALB C , Células Th1/metabolismo
14.
J Vector Borne Dis ; 54(2): 139-145, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28748834

RESUMO

BACKGROUND & OBJECTIVES: Malaria is a life-threatening disease caused by Plasmodium parasites. The life-cycle of Plasmodium species involves several stages both in mosquito and the vertebrate host. In the erythrocytic stage, Plasmodium resides inside the red blood cells (RBCs), where it meets most of its nutritional requirement by degrad- ing host's haemoglobin. L-arginine is required for growth and division of cells. The present study was aimed to demonstrate the effect of supplementation of different concentrations of L-arginine and L-citrulline on the growth of parasite, and effect of the culture supernatant on the host's peripheral blood mononuclear cells (PBMCs). METHODS: To examine the effect of supplementation of L-arginine and L-citrulline, Plasmodium falciparum (3D7 strain) was cultured in RPMI 1640, L-arginine deficient RPMI 1640, and in different concentrations of L-arginine, and L-citrulline supplemented in arginine deficient RPMI 1640 medium. To have a holistic view of in vivo cell activation, the PBMCs isolated from healthy human host were cultured in the supernatant collected from P. falciparum culture. RESULTS: Growth of the parasite was greatly enhanced in L-arginine supplemented media and was found to be concentration dependent. However, parasite growth was compromised in L-citrulline supplemented and L-arginine deficient media. The supernatant collected from L-arginine supplemented parasite media (sArg) showed increased FOXP3 and interleukin-10 (IL-10) expression as compared to the supernatant collected from L-citrulline supple- mented parasite media (sCit). INTERPRETATION & CONCLUSION: The in vitro culture results showed, decreased parasite growth, and decreased expression of programmed cell death-1 (PD-1) (a coinhibitory molecule) and IL-10 in the L-citrulline supplemented media as compared to L-arginine supplemented media. Hence, it was concluded that L-citrulline supplementation would be a better alternative than L-arginine to inhibit the parasite growth.


Assuntos
Arginina/metabolismo , Leucócitos Mononucleares/imunologia , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/imunologia , Células Cultivadas , Citrulina/metabolismo , Meios de Cultivo Condicionados , Humanos , Plasmodium falciparum/metabolismo
15.
Braz J Microbiol ; 55(1): 343-355, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38066229

RESUMO

Sulfonamide derivatives have numerous pharmaceutical applications having antiviral, antibacterial, antifungal, antimalarial, anticancer, and antidepressant activities. The structural flexibility of sulfonamide derivatives makes them an excellent candidate for the development of new multi-target agents, although long-time exposure to sulfonamide drugs results in many toxic impacts on human health. However, sulfonamides may be functionalized for developing less toxic and more competent drugs. In this work, sulfonamides including Sulfapyridine (a), Sulfathiazole (b), Sulfamethoxazole (c), and Sulfamerazine (d) are used to synthesize Schiff bases of 7-hydroxy-4-methyl-2-oxo-2H-chromene-8-carbalde-hyde (1a-1d). The synthesized compounds were spectroscopically characterized and tested against hospital isolates of three Gram-positive (Methicillin-resistant Staphylococcus aureus PH217, Ampicillin-resistant Coagulase-negative Staphylococcus aureus, multidrug-resistant (MDR) Enterococcus faecalis PH007R) and two Gram-negative bacteria (multidrug-resistant Escherichia coli, and Salmonella enterica serovar Typhi), compared to the quality control strains from ATCC (S. aureus 29213, E. faecalis 25922, E. coli 29212) and MTCC (S. Typhi 734). Two of the four Schiff bases 1a and 1b are found to be more active than their counterpart 1c and 1d; while 1a have showed significant activity by inhibiting MRSA PH217 and MDR isolates of E. coli at the minimum inhibitory concentration (MIC) of 150 µg/mL and 128 µg/mL with MBC of 1024 µg/mL, respectively. On the other hand, the MIC of 1b was 150 µg/mL against both S. aureus ATCC 29213 and Salmonella Typhi MTCC 734, compared to the control antibiotics Ampicillin and Gentamycin. Scanning electron microscopy demonstrated the altered surface structure of bacterial cells as a possible mechanism of action, supported by the in-silico molecular docking analysis.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Staphylococcus aureus , Humanos , Simulação de Acoplamento Molecular , Cromonas/farmacologia , Escherichia coli , Bases de Schiff/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Sulfanilamida , Ampicilina/farmacologia , Sulfonamidas/farmacologia , Testes de Sensibilidade Microbiana
16.
Int J Biol Macromol ; 265(Pt 2): 130747, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38479657

RESUMO

Exopolysaccharides (EPSs), originating from various microbes, and mushrooms, excel in their conventional role in bioremediation to showcase diverse applications emphasizing nanobiotechnology including nano-drug carriers, nano-excipients, medication and/or cell encapsulation, gene delivery, tissue engineering, diagnostics, and associated treatments. Acknowledged for contributions to adsorption, nutrition, and biomedicine, EPSs are emerging as appealing alternatives to traditional polymers, for biodegradability and biocompatibility. This article shifts away from the conventional utility to delve deeply into the expansive landscape of EPS applications, particularly highlighting their integration into cutting-edge nanobiotechnological methods. Exploring EPS synthesis, extraction, composition, and properties, the discussion emphasizes their structural diversity with molecular weight and heteropolymer compositions. Their role as raw materials for value-added products takes center stage, with critical insights into recent applications in nanobiotechnology. The multifaceted potential, biological relevance, and commercial applicability of EPSs in contemporary research and industry align with the nanotechnological advancements coupled with biotechnological nano-cleansing agents are highlighted. EPS-based nanostructures for biological applications have a bright future ahead of them. Providing crucial information for present and future practices, this review sheds light on how eco-friendly EPSs derived from microbial biomass of terrestrial and aquatic environments can be used to better understand contemporary nanobiotechnology for the benefit of society.


Assuntos
Nanoestruturas , Polissacarídeos Bacterianos , Polissacarídeos Bacterianos/química , Biotecnologia , Portadores de Fármacos , Nanotecnologia
17.
J Biol Chem ; 287(40): 33656-63, 2012 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-22810226

RESUMO

Mycobacterium tuberculosis, the causative agent of tuberculosis (TB), resides and replicates within phagocytes and persists in susceptible hosts by modulating protective innate immune responses. Furthermore, M. tuberculosis promotes T helper 2 (Th2) immune responses by altering the balance of T cell polarizing cytokines in infected cells. However, cytokines that regulate Th2 cell differentiation during TB infection remain unknown. Here we show that IL-1ß, produced by phagocytes infected by virulent M. tuberculosis strain H37Rv, directs Th2 cell differentiation. In sharp contrast, the vaccine strain bacille Calmette-Guérin as well as RD-1 and ESAT-6 mutants of H37Rv failed to induce IL-1ß and promote Th2 cell differentiation. Furthermore, ESAT-6 induced IL-1ß production in dendritic cells (DCs), and CD4(+) T cells co-cultured with infected DCs differentiated into Th2 cells. Taken together, our findings indicate that IL-1ß induced by RD-1/ESAT-6 plays an important role in the differentiation of Th2 cells, which in turn facilitates progression of TB by inhibiting host protective Th1 responses.


Assuntos
Células Dendríticas/citologia , Interleucina-1beta/metabolismo , Mycobacterium tuberculosis/metabolismo , Células Th2/citologia , Animais , Diferenciação Celular , Técnicas de Cocultura , Citocinas/metabolismo , Células Dendríticas/microbiologia , Sistema Imunitário , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Fagócitos/citologia , Células Th2/microbiologia , Tuberculose/imunologia , Tuberculose/microbiologia
18.
PLoS Pathog ; 7(11): e1002378, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22102818

RESUMO

Despite its relatively poor efficacy, Bacillus Calmette-Guérin (BCG) has been used as a tuberculosis (TB) vaccine since its development in 1921. BCG induces robust T helper 1 (Th1) immune responses but, for many individuals, this is not sufficient for host resistance against Mycobacterium tuberculosis (M. tb) infection. Here we provide evidence that early secreted antigenic target protein 6 (ESAT-6), expressed by the virulent M. tb strain H37Rv but not by BCG, promotes vaccine-enhancing Th17 cell responses. These activities of ESAT-6 were dependent on TLR-2/MyD88 signalling and involved IL-6 and TGF-ß production by dendritic cells. Thus, animals that were previously infected with H37Rv or recombinant BCG containing the RD1 region (BCG::RD1) exhibited improved protection upon re-challenge with virulent H37Rv compared with mice previously infected with BCG or RD1-deficient H37Rv (H37RvΔRD1). However, TLR-2 knockout (TLR-2⁻/⁻) animals neither showed Th17 responses nor exhibited improved protection in response to immunization with H37Rv. Furthermore, H37Rv and BCG::RD1 infection had little effect on the expression of the anti-inflammatory microRNA-146a (miR146a) in dendritic cells (DCs), whereas BCG and H37RvΔRD1 profoundly induced its expression in DCs. Consistent with these findings, ESAT-6 had no effect on miR146a expression in uninfected DCs, but dramatically inhibited its upregulation in BCG-infected or LPS-treated DCs. Collectively, our findings indicate that, in addition to Th1 immunity induced by BCG, RD1/ESAT-6-induced Th17 immune responses are essential for optimal vaccine efficacy.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Mycobacterium tuberculosis/imunologia , Células Th17/imunologia , Receptor 2 Toll-Like/imunologia , Tuberculose/imunologia , Animais , Antígenos de Bactérias/metabolismo , Vacina BCG/imunologia , Proteínas de Bactérias/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Interleucina-6/biossíntese , Pulmão/imunologia , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mycobacterium bovis/imunologia , Mycobacterium bovis/patogenicidade , Mycobacterium tuberculosis/metabolismo , Mycobacterium tuberculosis/patogenicidade , Fator 88 de Diferenciação Mieloide/metabolismo , Células Th1/imunologia , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Fator de Crescimento Transformador beta/biossíntese , Tuberculose/prevenção & controle
19.
Pharm Biol ; 51(6): 677-85, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23527893

RESUMO

CONTEXT: Scientific validation of an ethnomedicinal combination consisting of Semecarpus kurzii Engler (Anacardeaceae) leaves (SKL) and Hernandia peltata Meisn (Hernandeaceae) stem-bark (HPB), traditionally used in ailments related to inflammation, pain and fever. OBJECTIVE: To validate in vivo and in vitro analgesic and antiinflammatory activities of methanol extract of SKL, HPB and their combination. MATERIALS AND METHODS: Analgesic activity was tested by acetic acid induced writhing reflex and tail flick in Swiss albino mice, while the anti-inflammatory activity was studied in acute, subacute and chronic model on Wistar rats. The vascular permeability, membrane stabilization and protein denaturation were examined to know the possible mode of action. RESULTS: Significant (p < 0.01) analgesic (78.04% inhibition of writhing) and antiinflammatory (72.54% inhibition of paw edema) activity was observed in combination of SKL and HPB extracts at 250 mg/kg each. The SKL extract alone inhibits acetic acid-induced vascular permeability (64.4%) at 500 mg/kg, while in combination at 250 mg/kg each, the inhibition was 69.49% (p < 0.01). Furthermore, SKL in combination with HPB (0.25 mg/mL each) prevent RBC hemolysis (61.91%) and inhibition of protein denaturation (76.52%)-like indomethacin. DISCUSSION AND CONCLUSION: The SKL and HPB extract, alone (500 mg/kg) and in combination, (250 mg/kg each) had significant analgesic and antiinflammatory activity, probably by inhibiting the release of certain inflammatory mediators and membrane stabilization, due to the presence of triterpenes, tannins and related phytochemicals in the extracts. Thus, our results demonstrated that this combination provide the scientific rationale of its folk use.


Assuntos
Hernandiaceae/química , Extratos Vegetais/farmacologia , Semecarpus/química , Dor Aguda/tratamento farmacológico , Analgésicos/administração & dosagem , Analgésicos/isolamento & purificação , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Dor Crônica/tratamento farmacológico , Modelos Animais de Doenças , Quimioterapia Combinada , Inflamação/tratamento farmacológico , Mediadores da Inflamação/metabolismo , Masculino , Medicina Tradicional , Camundongos , Casca de Planta , Extratos Vegetais/administração & dosagem , Folhas de Planta , Caules de Planta , Ratos , Ratos Wistar
20.
J Integr Med ; 21(3): 226-235, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36932029

RESUMO

Diabetes mellitus is a chronic disease, typified by hyperglycemia resulting from failures in complex multifactorial metabolic functions, that requires life-long medication. Prolonged uncontrolled hyperglycemia leads to micro- and macro-vascular complications. Although antidiabetic drugs are prescribed as the first-line treatment, many of them lose efficacy over time or have severe side effects. There is a lack of in-depth study on the patents filed concerning the use of natural compounds to manage diabetes. Thus, this patent analysis provides a comprehensive report on the antidiabetic therapeutic activity of 6 phytocompounds when taken alone or in combinations. Four patent databases were searched, and 17,649 patents filed between 2001 and 2021 were retrieved. Of these, 139 patents for antidiabetic therapeutic aids that included berberine, curcumin, gingerol, gymnemic acid, gymnemagenin and mangiferin were analyzed. The results showed that these compounds alone or in combinations, targeting acetyl-coenzyme A carboxylase 2, serine/threonine protein kinase, α-amylase, α-glucosidase, lipooxygenase, phosphorylase, peroxisome proliferator-activated receptor-γ (PPARγ), protein tyrosine phosphatase 1B, PPARγ co-activator-1α, phosphoinositide 3-kinase and protein phosphatase 1 regulatory subunit 3C, could regulate glucose metabolism which are validated by pharmacological rationale. Synergism, or combination therapy, including different phytocompounds and plant extracts, has been studied extensively and found effective, whereas the efficacy of commercial drugs in combination with phytocompounds has not been studied in detail. Curcumin, gymnemic acid and mangiferin were found to be effective against diabetes-related complications. Please cite this article as: DasNandy A, Virge R, Hegde HV, Chattopadhyay D. A review of patent literature on the regulation of glucose metabolism by six phytocompounds in the management of diabetes mellitus and its complications. J Integr Med. 2023; 21(3): 226-235.


Assuntos
Curcumina , Diabetes Mellitus , Hiperglicemia , Humanos , PPAR gama/metabolismo , Curcumina/uso terapêutico , Fosfatidilinositol 3-Quinases , Diabetes Mellitus/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Hipoglicemiantes/farmacologia , Hiperglicemia/induzido quimicamente , Hiperglicemia/tratamento farmacológico , Glucose
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