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1.
Microorganisms ; 11(10)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37894118

RESUMO

Valacyclovir (VACV) was developed as a prodrug of the most common anti-herpetic drug Acyclovir (ACV), aiming to enhance its bioavailability. Nevertheless, prolonged VACV oral treatment may lead to the development of important side effects. Nanotechnology-based formulations for vaginal administration represent a promising approach to increase the concentration of the drug at the site of infection, limiting systemic drug exposure and reducing systemic toxicity. In this study, VACV-loaded nanodroplet (ND) formulations, optimized for vaginal delivery, were designed. Cell-based assays were then carried out to evaluate the antiviral activity of VACV loaded in the ND system. The chitosan-shelled ND exhibited an average diameter of about 400 nm and a VACV encapsulation efficiency of approximately 91% and was characterized by a prolonged and sustained release of VACV. Moreover, a modification of chitosan shell with an anionic cyclodextrin, sulfobutyl ether ß-cyclodextrin (SBEßCD), as a physical cross-linker, increased the stability and mucoadhesion capability of the nanosystem. Biological experiments showed that SBEßCD-chitosan NDs enhanced VACV antiviral activity against the herpes simplex viruses type 1 and 2, most likely due to the long-term controlled release of VACV loaded in the ND and an improved delivery of the drug in sub-cellular compartments.

2.
Pediatr Res ; 94(3): 956-964, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37059899

RESUMO

BACKGROUND: There is extensive evidence that Holder pasteurization (HoP) (30 min at 62.5 °C) has harmful effects on the bioactivities of human milk (HM). We previously demonstrated that lowering HoP temperature is sufficient to inactivate Cytomegalovirus (HCMV). Here, we analyzed the effect of lowering time/temperature on the antiviral activity against HCMV and IgA levels of HM. METHODS: Eighty HM samples from five mothers were pasteurized in a range of temperature (62.5-56 °C) and time (40-10 min) in a conventional setting of Human Milk Bank. Unpasteurized HM from each mother was used as control. The samples were assayed against HCMV-AD169 strain in cell cultures and IgA levels were determined by ELISA. RESULTS: All HM samples exhibited anti-HCMV activity, to a different extent. An improvement of antiviral activity was observed in samples treated at 60, 58 and 56 °C compared to those at 62.5 °C, with ID50 values near those of unpasteurized milk. Similarly, better retention in IgA levels was observed by reducing the temperature of treatment. CONCLUSIONS: We demonstrated that a 2.5 °C reduction of heat treatment significantly preserved the IgA content and fully restored the anti-HCMV activity of HM, supporting this variant of HoP as a valid alternative to preserve HM bioactivities. IMPACT: This work questions the standard HoP and opens the debate on whether the pasteurization temperature commonly used in Human Milk Banks should be lowered to better preserve the biological components of the milk. A reduction of HoP temperature at 60 °C determined a significant preservation of anti-HCMV activity and IgA content of donor HM, compared to standard HoP. This alternative HoP is highly feasible compared to other substitute pasteurization techniques, since it would employ the same pasteurizer equipment found in most Human Milk Banks.


Assuntos
Bancos de Leite Humano , Leite Humano , Humanos , Temperatura , Pasteurização/métodos , Imunoglobulina A , Antivirais/farmacologia
3.
Panminerva Med ; 65(1): 20-22, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32700882

RESUMO

BACKGROUND: Acute E hepatitis is usually a self-limited non-progressive disease; however, acute liver failure and death can occur in the presence of conditions such as pregnancy and chronic liver diseases. In immunocompromised individuals, such as transplant patients, acute hepatitis E virus (HEV) infection may evolve to chronic hepatitis with rapid progression to liver decompensation. At our center, serology for HEV is not routinely performed in transplant patients and serological status is investigated only based on clinical judgement. METHODS: In this study, seroprevalence of HEV was evaluated in 217 patients (120 liver transplant recipients and 97 individuals diagnosed with acute or chronic hepatitis). Molecular evaluation of HEV-RNA was also performed. RESULTS: Thirteen patients (6%) showed positivity for HEV-IgG; in particular, 10/120 (8.3%), with concomitant presence of IgM and IgG in six and 3/97 (3.1%). None of the plasma samples tested by HEV-RNA was positive. CONCLUSIONS: As the detectable RNA window is narrow and an undetectable HEV-RNA result does not exclude recent infection and the transplant context per se represents a risk factor for chronic infection in patients infected with HEV, a routine diagnostic workflow including HEV should be taken into consideration, increasing awareness and knowledge of the basic and clinical aspects of the disease.


Assuntos
Vírus da Hepatite E , Hepatite E , Transplante de Fígado , Humanos , Vírus da Hepatite E/genética , Transplante de Fígado/efeitos adversos , Estudos Soroepidemiológicos , RNA Viral , Hepatite E/diagnóstico , Hepatite E/epidemiologia , Hepatite Crônica/complicações , Itália/epidemiologia , Imunoglobulina G
4.
Pediatr Res ; 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35513714

RESUMO

BACKGROUND: The antiviral role of glycosaminoglycans in human milk (HM-GAGs) has been poorly investigated. They are highly sulfated polysaccharides, which were proposed to act as decoy receptors according to their structure. The aim of this study is to evaluate the antiviral potential and the mechanism of action of total and individual HM-GAGs against three pediatric clinically relevant viruses: respiratory syncytial virus (RSV), cytomegalovirus (HCMV), and rotavirus. METHODS: HM-GAGs were isolated from HM and a library of individual GAGs, structurally related to HM-GAGs, was prepared. The antiviral activity of HM-GAGs and the impact of thermal treatment were investigated in vitro by specific antiviral assays. RESULTS: We demonstrated that HM-GAGs are endowed with anti-HCMV and anti-RSV activity and that they act by altering virus attachment to cell. We clarified the contribution of individual HM-GAGs, showing a specific structure-related activity. We did not observe any alteration of HM-GAG antiviral activity after thermal treatment. CONCLUSIONS: We showed that HM-GAGs contribute to the overall antiviral activity of HM, likely exerting a synergic action with other HM antiviral agents. HM-GAGs can now be added to the list of endogenous factors that may reduce breast-milk-acquired HCMV symptomatic infections and protecting infants from respiratory tract infections by RSV. IMPACT: HM-GAGs have been poorly investigated for their antiviral action so far. We demonstrated that HM-GAGs are endowed with significant anti-HCMV and anti-RSV activity and that they are able to alter virus binding to the cell. The contribution of individual HM-GAGs is mainly exerted by the FMHep and is not based on a simple charge interaction between the virus and sulfate groups but involves a specific GAG structural configuration. Our results contribute to identifying the multiple factors synergically acting in mediating HM antiviral properties and to clarifying their specific mechanism of action.

5.
Int J Mol Sci ; 23(2)2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35055133

RESUMO

Herpesviruses are highly prevalent in the human population, and frequent reactivations occur throughout life. Despite antiviral drugs against herpetic infections, the increasing appearance of drug-resistant viral strains and their adverse effects prompt the research of novel antiherpetic drugs for treating lesions. Peptides obtained from natural sources have recently become of particular interest for antiviral therapy applications. In this work, we investigated the antiviral activity of the peptide A-3302-B, isolated from a marine bacterium, Micromonospora sp., strain MAG 9-7, against herpes simplex virus type 1, type 2, and human cytomegalovirus. Results showed that the peptide exerted a specific inhibitory activity against HSV-2 with an EC50 value of 14 µM. Specific antiviral assays were performed to investigate the mechanism of action of A-3302-B. We demonstrated that the peptide did not affect the expression of viral proteins, but it inhibited the late events of the HSV-2 replicative cycle. In detail, it reduced the cell-to-cell virus spread and the transmission of the extracellular free virus by preventing the egress of HSV-2 progeny from the infected cells. The dual antiviral and previously reported anti-inflammatory activities of A-3302-B, and its effect against an acyclovir-resistant HSV-2 strain are attractive features for developing a therapeutic to reduce the transmission of HSV-2 infections.


Assuntos
Antivirais/farmacologia , Herpesvirus Humano 2/fisiologia , Micromonospora/química , Peptídeos/farmacologia , Animais , Antivirais/química , Antivirais/isolamento & purificação , Chlorocebus aethiops , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/fisiologia , Prepúcio do Pênis/citologia , Prepúcio do Pênis/virologia , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 1/fisiologia , Herpesvirus Humano 2/efeitos dos fármacos , Humanos , Masculino , Estrutura Molecular , Peptídeos/química , Peptídeos/isolamento & purificação , Células Vero , Liberação de Vírus/efeitos dos fármacos
6.
Front Pediatr ; 9: 640638, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34386465

RESUMO

One of the main concerns in human milk banks (HMB) is the transmission of human cytomegalovirus (HCMV) that could be present in the milk of infected women. There are consistent data showing that this virus is destroyed by Holder pasteurization (62.5°C for 30 min), but there is a lack of information about the response of the virus to the treatment at lower temperatures in strict HMB conditions. In order to analyze the effectiveness of different temperatures of pasteurization to eliminate HCMV in human milk, a preliminary assay was performed incubating HCMV-spiked raw milk samples from donor mothers at tested temperatures in a PCR thermocycler and the viral infectivity was assayed on cell cultures. No signs of viral replication were observed after treatments at temperatures equal or >53°C for 30, 20, and 10 min, 58°C for 5 min, 59°C for 2 min, and 60°C for 1 min. These data were confirmed in a pasteurizer-like model introducing HCMV-spiked milk in disposable baby bottles. No viral infectivity was detected on cell cultures after heating treatment of milk for 30 min at temperatures from 56 to 60°C. Thus, our results show that by using conventional pasteurization conditions, temperatures in the range of 56-60°C are enough to inactivate HCMV. Consequently, we consider that, in order to provide a higher quality product, the current recommendation to pasteurize both mother's own milk and donated milk at 62.5°C must be re-evaluated.

7.
Planta Med ; 86(18): 1363-1374, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32937663

RESUMO

Zika virus, an arthropod-borne flavivirus, is an emerging healthcare threat worldwide. Zika virus is responsible for severe neurological effects, such as paralytic Guillain-Barrè syndrome, in adults, and also congenital malformations, especially microcephaly. No specific antiviral drugs and vaccines are currently available, and treatments are palliative, but medicinal plants show great potential as natural sources of anti-Zika phytochemicals. This study deals with the investigation of the composition, cytotoxicity, and anti-Zika activity of Punica granatum leaf ethanolic extract, fractions, and phytoconstituents. P. granatum leaves were collected from different areas in Italy and Greece in different seasons. Crude extracts were analyzed and fractionated, and the pure compounds were isolated. The phytochemical and biomolecular fingerprint of the pomegranate leaves was determined. The antiviral activities of the leaf extract, fractions, and compounds were investigated against the MR766 and HPF2013 Zika virus strains in vitro. Both the extract and its fractions were found to be active against Zika virus infection. Of the compounds isolated, ellagic acid showed particular anti-Zika activities, with EC50 values of 30.86 µM for MR766 and 46.23 µM for HPF2013. The mechanism of action was investigated using specific antiviral assays, and it was demonstrated that ellagic acid was primarily active as it prevented Zika virus infection and was able to significantly reduce Zika virus progeny production. Our data demonstrate the anti-Zika activity of pomegranate leaf extract and ellagic acid for the first time. These findings identify ellagic acid as a possible anti-Zika candidate compound that can be used for preventive and therapeutic interventions.


Assuntos
Infecção por Zika virus , Zika virus , Ácido Elágico/farmacologia , Humanos , Compostos Fitoquímicos , Punica granatum , Infecção por Zika virus/tratamento farmacológico
8.
Int J Pharm ; 587: 119676, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32738458

RESUMO

Acyclovir is the gold standard drug for herpes simplex virus type 2 (HSV-2) infection treatment. Vaginal topical therapy with acyclovir is hampered due to its poor bioavailability, low retention at the vaginal mucosa, thus requiring high doses and frequent administrations. Nanocarriers have been proposed to overcome the challenges associated with antiviral delivery. This work aims at developing a novel formulation consisting of sulfobutyl ether-ß-cyclodextrin decorated nanodroplets for acyclovir topical delivery to improve its antiviral effectiveness. To obtain acyclovir-loaded nanodroplets, the drug was previously complexed with sulfobutyl ether-ß-cyclodextrin, and then incorporated in the nanodroplet chitosan shell via electrostatic interaction. The acyclovir-cyclodextrin inclusion complex was characterized by phase solubility, DSC, FTIR studies. The nanodroplets showed an average diameter of about 400 nm and positive surface charge. Acyclovir was efficiently incorporated in the nanodroplets (about 97% of encapsulation efficiency) and slowly released over time. The acyclovir-loaded nanodroplets exhibited an enhanced antiviral activity compared to the free drug against HSV-2 in cell cultures, which might be ascribed to a higher intracellular accumulation of the drug in nanodroplet-treated cells than in free acyclovir-treated cells. Based on these results, this new nanoformulation paves the way for the development of a future nanomicrobicide for the HSV-2 infections.


Assuntos
Quitosana , beta-Ciclodextrinas , Aciclovir , Antivirais , Éteres , Feminino , Herpesvirus Humano 2 , Humanos
9.
Microorganisms ; 8(7)2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32708203

RESUMO

Breast milk is a complex biofluid that nourishes infants, supports their growth and protects them from diseases. However, at the same time, breastfeeding is a transmission route for human cytomegalovirus (HCMV), with preterm infants being at a great risk of congenital disease. The discrepancy between high HCMV transmission rates and the few reported cases of infants with severe clinical illness is likely due to the protective effect of breast milk. The aim of this study was to investigate the anti-HCMV activity of human preterm colostrum and clarify the role of colostrum-derived extracellular vesicles (EVs). Preterm colostrum samples were collected and the EVs were purified and characterized. The in vitro anti-HCMV activity of both colostrum and EVs was tested against HCMV, and the viral replication step inhibited by colostrum-purified EVs was examined. We investigated the putative role EV surface proteins play in impairing HCMV infection using shaving experiments and proteomic analysis. The obtained results confirmed the antiviral action of colostrum against HCMV and demonstrated a remarkable antiviral activity of colostrum-derived EVs. Furthermore, we demonstrated that EVs impair the attachment of HCMV to cells, with EV surface proteins playing a role in mediating this action. These findings contribute to clarifying the mechanisms that underlie the protective role of human colostrum against HCMV infection.

10.
New Microbiol ; 43(2): 93-95, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32310302

RESUMO

Cytomegalovirus is the primary viral cause of congenital infection. However, diagnosis may be difficult for clinical and technical reasons. Currently, evaluation of CMV DNA on dried blood spot (DBS) is an important instrument to define a congenital infection. The aim of this study was to identify a clinically and technically suitable diagnostic work-flow for CMV DNA evaluation on DBS. Sensitivity was not significantly influenced by storage time of up to 12 months and extraction technique; however, analysis in triplicate was crucial to obtain reliable results. Considering viral load in an infected foetus at risk of developing disease, a threshold value of approximately 104 copies/mL was characterized by high operating characteristics for detection of positivity at 12 months on DBS.


Assuntos
Infecções por Citomegalovirus , Citomegalovirus , DNA Viral , Teste em Amostras de Sangue Seco , Citomegalovirus/genética , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/virologia , DNA Viral/química , Teste em Amostras de Sangue Seco/normas , Humanos , Sensibilidade e Especificidade , Testes Sorológicos , Carga Viral
11.
Planta Med ; 86(4): 267-275, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31968380

RESUMO

Infections caused by HSV-2 are a public health concern worldwide, and there is still a great demand for the discovery of novel anti-herpes virus agents effective against strains resistant to current antiviral agents. In this context, medicinal plants represent an alternative source of active compounds for developing efficient antiviral therapies. The aim of this study was to evaluate the antiviral activity of Arisaema tortuosum, a plant used in the traditional medicine of India. A chloroform soluble fraction of the leaves exhibited anti-HSV-2 activity with a selectivity index of 758. The extract was also active against acyclovir-resistant HSV-2 and HSV-1. The mechanism of action of the extract was investigated evidencing inhibition of both early and late events of the HSV-2 replicative cycle. A HPLC-PDA-MS/MS analysis showed the presence of flavonoids including apigenin and luteolin in the chloroform extract (CE). Apigenin and luteolin showed a high inhibitory activity with EC50 values of 0.05 and 0.41 µg/mL, respectively. Both compounds exhibited antiviral activity when added up to 6 h post infection and were able to reduce the viral progeny production. In addition, apigenin interfered with cell-to-cell virus spread.


Assuntos
Antivirais , Arisaema , Herpes Simples , Herpesvirus Humano 2 , Índia , Extratos Vegetais , Espectrometria de Massas em Tandem , Células Vero
12.
Antiviral Res ; 163: 29-33, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30653996

RESUMO

Zika virus (ZIKV) is an emerging infectious viral pathogen associated with severe fetal cerebral anomalies and the paralytic Guillain-Barrè syndrome in adults. It was the cause of a recent global health crisis following its entrance into a naïve population in the Americas. Nowadays, no vaccine or specific antiviral against ZIKV is available. In this study, we identified three polyoxometalates (POMs), the Anderson-Evans type [TeW6O24]6- (TeW6), and the Keggin-type [TiW11CoO40]8-_ (TiW11Co), and [Ti2PW10O40]7- (Ti2PW10), that inhibit ZIKV infection with EC50s in the low micromolar range. Ti2PW10, the POM with the greatest selectivity index (SI), was selected and the step of ZIKV replicative cycle putatively inhibited was investigated by specific antiviral assays. We demonstrated that Ti2PW10 targets the entry process of ZIKV infection and it is able to significantly reduce ZIKV progeny production. These results suggest that the polyanion Ti2PW10 could be a good starting point to develop an effective therapeutic to treat ZIKV infection.


Assuntos
Antivirais/farmacologia , Compostos de Tungstênio/farmacologia , Internalização do Vírus/efeitos dos fármacos , Zika virus/efeitos dos fármacos , Animais , Antivirais/química , Chlorocebus aethiops , Compostos de Tungstênio/química , Células Vero , Replicação Viral/efeitos dos fármacos , Zika virus/fisiologia
13.
Int J Biol Macromol ; 124: 131-137, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30471396

RESUMO

In the current study, fucoidans from brown alga Nizamuddinia zanardinii were isolated with conventional and non-conventional extraction procedures to evaluate the effects of recently introduced technologies on biochemical characteristics and saccharide composition of the extracts, along with their antibacterial, antiviral and cytotoxic properties. The results demonstrated that subcritical water extraction showed the highest fucoidans yield (13.15%), while the lowest yield was obtained using ultrasound extraction method (3.6%). The polysaccharide chains consisted of fucose, galactose, glucose, mannose and xylose, whose molar percentages differed according to the extraction method used. The weight mean average molecular weight of fucoidans varied between 444 and 1184 kDa. The FT-IR spectroscopy confirmed the presence of sulfate esters by bending vibration of COS and stretching vibration of SO peaks at 818 and 1250 cm-1, respectively. Antibacterial assays showed that microwave- and subcritical water-extracted fucoidans inhibited the growth of E.coli and that enzyme-ultrasound, ultrasound-microwave and subcritical water extracted fucoidans exhibited inhibitory effects against P. aeruginosa at 2 mg/mL. Antiviral studies revealed that all the extracted fucoidans exerted strong antiviral activity against HSV-2 infection, with EC50 values in the 0.027-0.123 µg/mL range; indeed the viscozyme-extracted macromolecules displayed the best selectivity index.


Assuntos
Antibacterianos/farmacologia , Phaeophyceae/química , Polissacarídeos/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/patogenicidade , Humanos , Peso Molecular , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidade , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfatos/química
14.
Front Pediatr ; 6: 304, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30460212

RESUMO

Holder pasteurization (62. 5°C for 30 min) is recommended by all international human milk bank guidelines to prevent infections potentially transmitted by donor human milk. A drawback is that it affects some human milk bioactive and nutritive components. Recently, High Temperature-Short Time (HTST) pasteurization has been reported to be a valuable alternative technology to increase the retention of some biological features of human milk. Nevertheless, to date, few data are available about the impact of pasteurization methods other than Holder on the antiviral activity of human milk. The present study was aimed at evaluating the antiviral activity of human milk against a panel of viral pathogens common in newborns and children (i.e., herpes simplex virus 1 and 2, cytomegalovirus, respiratory syncytial virus, rotavirus, and rhinovirus), and at assessing the effect of Holder and HTST pasteurization on milk's antiviral properties. The results indicate that human milk is endowed with antiviral activity against all viruses tested, although to a different extent. Unlike the Holder pasteurization, HTST preserved the inhibitory activity against cytomegalovirus, respiratory syncytial virus, rotavirus and herpes simplex virus type 2. By contrast, both methods reduced significantly the antiviral activities against rhinovirus and herpes simplex virus type 1. Unexpectedly, Holder pasteurization improved milk's anti-rotavirus activity. In conclusion, this study contributes to the definition of the pasteurization method that allows the best compromise between microbiological safety and biological quality of the donor human milk: HTST pasteurization preserved milk antiviral activity better than Holder.

15.
J Pediatr Gastroenterol Nutr ; 67(5): 654-659, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30074575

RESUMO

OBJECTIVES: This study aimed to investigate the anti-human cytomegalovirus (CMV) activity of milk from seropositive and seronegative mothers of preterm infants and to analyze its changes throughout the different stages of lactation and after Holder pasteurization, a procedure adopted by donor human milk banks. METHODS: Eighteen mothers of preterm infants were enrolled in the study. Colostrum, transitional milk, and mature milk samples were collected and tested for anti-CMV activity. Depletion of immunoglobulins A from milk samples was carried out by jacalin resin. Pools of milk samples were pasteurized according to Holder technique. RESULTS: All samples were endowed with anti-CMV activity, although to a different extent. In CMV IgG-positive mothers, colostra were significantly more active than the transitional milk and mature milk samples. Moreover, they were more potent than colostra from seronegative mothers. Immunoglobulins A depletion in colostra from IgG-positive mothers resulted in a partial loss of anti-CMV activity. Holder pasteurization significantly reduced the antiviral activity. CONCLUSIONS: Human milk is endowed with anti-CMV activity and its potency may vary depending on the stage of lactation and the serological status of the mother. This biological property could partially neutralize CMV particles excreted in the milk of CMV IgG-positive mothers thus reducing the risk of transmitting infectious viruses to the infant.


Assuntos
Anticorpos Antivirais/análise , Colostro/imunologia , Infecções por Citomegalovirus/imunologia , Citomegalovirus/imunologia , Leite Humano/imunologia , Adulto , Anticorpos Antivirais/imunologia , Infecções por Citomegalovirus/sangue , Infecções por Citomegalovirus/transmissão , Feminino , Humanos , Imunoglobulina A/análise , Imunoglobulina A/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Recém-Nascido , Recém-Nascido Prematuro , Transmissão Vertical de Doenças Infecciosas , Masculino , Bancos de Leite Humano , Mães , Pasteurização
16.
Phytother Res ; 32(8): 1555-1563, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29673001

RESUMO

Thymus capitatus represents 1 of the 5 Tunisian species of the genus Thymus, which has long­standing use for flavouring and preserving several food products. Its constituents have been reported to endow antimicrobial properties, but little is known about their antiviral activities. The aim of this study was to examine the antiviral activity of pure compounds from the most bioactive inhibitory T. capitatus extract in vitro against herpes simplex virus Type 2 (HSV­2) infection and to identify their mechanism of action. Either the extracts or the essential oil exert inhibitory activity against HSV­2 infection, with the ethanolic extract showing the lowest EC50 value (2.3 µg/ml). Three pure compounds were then isolated from the ethanolic extract and investigated for their antiviral activity. ß­sitosterol showed the most favourable selectivity index and both cinnamaldehyde and carvacrol exerted moderate antiviral effect. Investigation of the mechanism of action revealed that all three compounds directly inactivated the infectivity of the virus particles. These findings suggest the use of T. capitatus ethanolic extract as source of anti­HSV­2 pure compounds and warrant further studies to evaluate their therapeutic potential.


Assuntos
Antivirais/farmacologia , Herpesvirus Humano 2/efeitos dos fármacos , Extratos Vegetais/farmacologia , Thymus (Planta)/química , Acroleína/análogos & derivados , Acroleína/farmacologia , Animais , Chlorocebus aethiops , Cimenos , Monoterpenos/farmacologia , Óleos Voláteis/farmacologia , Células Vero , Inativação de Vírus
17.
J Ethnopharmacol ; 213: 403-408, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29203273

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Vachellia (Acacia) nilotica and other plants of this genus have been used in traditional medicine of Asian and African countries to treat many disorders, including sexually transmitted diseases, but few studies were performed to validate their anti-microbial and anti-viral activity against sexually transmitted infections. AIM OF THE STUDY: The present study was undertaken to explore whether the ethnomedical use of V.nilotica to treat genital lesions is substantiated by its antiviral activity against the human immunodeficiency virus (HIV), the herpes simplex virus (HSV) and the human papillomavirus (HPV). MATERIALS AND METHODS: The antiviral activity of V.nilotica was tested in vitro by virus-specific inhibition assays using HSV-2 strains, sensible or resistant to acyclovir, HIV-1IIIb strain and HPV-16 pseudovirion (PsV). The potential mode of action of extract against HSV-2 and HPV-16 was further investigated by virus inactivation and time-of-addition assays on cell cultures. RESULTS: V.nilotica chloroform, methanolic and water bark extracts exerted antiviral activity against HSV-2 and HPV-16 PsV infections; among these, methanolic extract showed the best EC50s with values of 4.71 and 1.80µg/ml against HSV-2 and HPV-16, respectively, and it was also active against an acyclovir-resistant HSV-2 strain with an EC50 of 6.71µg/ml. By contrast, no suppression of HIV infection was observed. Investigation of the mechanism of action revealed that the methanolic extract directly inactivated the infectivity of the HPV-16 particles, whereas a partial virus inactivation and interference with virus attachment (EC50 of 2.74µg/ml) were both found to contribute to the anti-HSV-2 activity. CONCLUSIONS: These results support the traditional use of V.nilotica applied externally for the treatment of genital lesions. Further work remains to be done in order to identify the bioactive components.


Assuntos
Acacia/química , Antivirais/farmacologia , HIV-1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Papillomavirus Humano 16/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Células Cultivadas , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Humanos , Casca de Planta/química , Extratos Vegetais/química , Ligação Viral/efeitos dos fármacos , Inativação de Vírus/efeitos dos fármacos
18.
New Microbiol ; 40(4): 251-257, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29184964

RESUMO

Cellular immunity plays a major role in the control of HSV-1 infection/reactivation with a potential impact on the clinical-therapeutic management of immunocompromised patients, such as transplant recipients. Herein, we quantitatively evaluated T-cell response directed at HSV-1 by a newly developed IFN-γ EliSPOT assay in 53 patients (including 45 lung transplant recipients and eight subjects in waiting list). Overall, 62.2% of transplant patients and 62.5% of subjects on the waiting list showed a response to HSV-1 with no significant difference in the level of virus-specific cellular immunity. Response tended to be lower in the first three months posttransplantation with a progressive recovery of pretransplantation status by the second year and in the presence of HSV-1 DNA positivity in bronchoalveolar lavage. As expected, no response was found in seronegative patients. No significant difference in the level of response according to IgM and IgG status was found. Further studies are required to define the role of HSV-1 specific immune response for the clinical-therapeutic management of lung transplant patients and in other clinical settings and to define cut-off levels discriminating between absence/low and strong response to be related to the risk of viral infection/reactivation.


Assuntos
ELISPOT/métodos , Herpes Simples/diagnóstico , Herpesvirus Humano 1/imunologia , Imunidade Celular , Transplante de Pulmão/efeitos adversos , Adulto , Feminino , Herpes Simples/virologia , Herpesvirus Humano 1/isolamento & purificação , Herpesvirus Humano 1/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia , Transplantados , Ativação Viral , Adulto Jovem
19.
Carcinogenesis ; 38(2): 218-229, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28025390

RESUMO

The landscape of HPV infection in racial/ethnic subgroups of head and neck cancer (HNC) patients has not been evaluated carefully. In this study, a meta-analysis examined the prevalence of HPV in HNC patients of African ancestry. Additionally, a pooled analysis of subject-level data was also performed to investigate HPV prevalence and patterns of p16 (CDNK2A) expression amongst different racial groups. Eighteen publications (N = 798 Black HNC patients) were examined in the meta-analysis, and the pooled analysis included 29 datasets comprised of 3,129 HNC patients of diverse racial/ethnic background. The meta-analysis revealed that the prevalence of HPV16 was higher among Blacks with oropharyngeal cancer than Blacks with non-oropharyngeal cancer. However, there was great heterogeneity observed among studies (Q test P<0.0001). In the pooled analysis, after adjusting for each study, year of diagnosis, age, gender and smoking status, the prevalence of HPV16/18 in oropharyngeal cancer patients was highest in Whites (61.1%), followed by 58.0% in Blacks and 25.2% in Asians (P<0.0001). There was no statistically significant difference in HPV16/18 prevalence in non-oropharyngeal cancer by race (P=0.682). With regard to the pattern of HPV16/18 status and p16 expression, White patients had the highest proportion of HPV16/18+/p16+ oropharyngeal cancer (52.3%), while Asians and Blacks had significantly lower proportions (23.0% and 22.6%, respectively) [P <0.0001]. Our findings suggest that the pattern of HPV16/18 status and p16 expression in oropharyngeal cancer appears to differ by race and this may contribute to survival disparities.

20.
Intervirology ; 60(4): 165-170, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29402852

RESUMO

BACKGROUND: The cytomegalovirus (CMV) UL55 gene encodes for a glycoprotein implicated in virus pathogenesis. Based on UL55 polymorphism, CMV has been divided into 4 genotypes. Previous studies investigated the possible role of genotypes in the clinical outcome of infection in different categories of patients; however, few data are available, particularly in the transplant setting and Italian case records. METHODS: Phylogenetic analysis through a maximum likelihood tree was used to evaluate the prevalence and distribution of CMV genotypes in whole blood specimens from 47 transplant patients and investigate the relation with demographic and clinical features. RESULTS: Overall, 40.4% of patients were classified as single genotype (12.8% gB1, 23.4% gB2, 4.2% gB3); mixed genotypes were detected in 59.6%. Genotype 4 was detected only in mixed cases. In comparison to single genotypes, mixed genotypes were more frequently associated with a higher duration of DNA viremia and higher peak viral load. CONCLUSIONS: Mixed infections seem to be prevalent in Italian transplant patients; it is likely that mixed infections are more difficult to control by immunological response in comparison to single genotype infections. In this context, the genetic profile of infecting viruses and relation to clinical outcome should be investigated, also taking into account the CMV-specific cellular immune response.


Assuntos
Infecções por Citomegalovirus/virologia , Citomegalovirus/classificação , Citomegalovirus/genética , Genótipo , Transplantados , Proteínas do Envelope Viral/genética , Adolescente , Adulto , Idoso , Sangue/virologia , Criança , Pré-Escolar , Coinfecção/epidemiologia , Coinfecção/virologia , Citomegalovirus/isolamento & purificação , Infecções por Citomegalovirus/epidemiologia , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Filogenia , Prevalência , Análise de Sequência de DNA , Adulto Jovem
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