Insights into Zika Virus Pathogenesis and Potential Therapeutic Strategies.

Zika virus (ZIKV) has emerged as a significant public health threat, reaching pandemic levels in 2016. Human infection with ZIKV can manifest as either asymptomatic or as an acute illness characterized by symptoms such as fever and headache. Moreover, it has been associated with severe neurological complications in adults, including Guillain-Barre syndrome, and devastating fetal abnormalities, like microcephaly. The primary mode of transmission is through Aedes spp. mosquitoes, and with half of the world's population residing in regions where Aedes aegypti, the principal vector, thrives, the reemergence of ZIKV remains a concern. This comprehensive review provides insights into the pathogenesis of ZIKV and highlights the key cellular pathways activated upon ZIKV infection. Additionally, we explore the potential of utilizing microRNAs (miRNAs) and phytocompounds as promising strategies to combat ZIKV infection.

The Azotobacter vinelandii AlgU regulon during vegetative growth and encysting conditions: A proteomic approach.

In the Pseduomonadacea family, the extracytoplasmic function sigma factor AlgU is crucial to withstand adverse conditions. Azotobacter vinelandii, a closed relative of Pseudomonas aeruginosa, has been a model for cellular differentiation in Gram-negative bacteria since it forms desiccation-resistant cysts. Previous work demonstrated the essential role of AlgU to withstand oxidative stress and on A. vinelandii differentiation, particularly for the positive control of alginate production. In this study, the AlgU regulon was dissected by a proteomic approach under vegetative growing conditions and upon encystment induction. Our results revealed several molecular targets that explained the requirement of this sigma factor during oxidative stress and extended its role in alginate production. Furthermore, we demonstrate that AlgU was necessary to produce alkyl resorcinols, a type of aromatic lipids that conform the cell membrane of the differentiated cell. AlgU was also found to positively regulate stress resistance proteins such as OsmC, LEA-1, or proteins involved in trehalose synthesis. A position-specific scoring-matrix (PSSM) was generated based on the consensus sequence recognized by AlgU in P. aeruginosa, which allowed the identification of direct AlgU targets in the A. vinelandii genome. This work further expands our knowledge about the function of the ECF sigma factor AlgU in A. vinelandii and contributes to explains its key regulatory role under adverse conditions.

Estimating mortality and disability in Peru before the COVID-19 pandemic: a systematic analysis from the Global Burden of the Disease Study 2019.

Background: Estimating and analyzing trends and patterns of health loss are essential to promote efficient resource allocation and improve Peru's healthcare system performance. Methods: Using estimates from the Global Burden of Disease (GBD), Injuries, and Risk Factors Study (2019), we assessed mortality and disability in Peru from 1990 to 2019. We report demographic and epidemiologic trends in terms of population, life expectancy at birth (LE), mortality, incidence, prevalence, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) caused by the major diseases and risk factors in Peru. Finally, we compared Peru with 16 countries in the Latin American (LA) region. Results: The Peruvian population reached 33.9 million inhabitants (49.9% women) in 2019. From 1990 to 2019, LE at birth increased from 69.2 (95% uncertainty interval 67.8-70.3) to 80.3 (77.2-83.2) years. This increase was driven by the decline in under-5 mortality (-80.7%) and mortality from infectious diseases in older age groups (+60 years old). The number of DALYs in 1990 was 9.2 million (8.5-10.1) and reached 7.5 million (6.1-9.0) in 2019. The proportion of DALYs due to non-communicable diseases (NCDs) increased from 38.2% in 1990 to 67.9% in 2019. The all-ages and age-standardized DALYs rates and YLLs rates decreased, but YLDs rates remained constant. In 2019, the leading causes of DALYs were neonatal disorders, lower respiratory infections (LRIs), ischemic heart disease, road injuries, and low back pain. The leading risk factors associated with DALYs in 2019 were undernutrition, high body mass index, high fasting plasma glucose, and air pollution. Before the COVID-19 pandemic, Peru experienced one of the highest LRIs-DALYs rates in the LA region. Conclusion: In the last three decades, Peru experienced significant improvements in LE and child survival and an increase in the burden of NCDs and associated disability. The Peruvian healthcare system must be redesigned to respond to this epidemiological transition. The new design should aim to reduce premature deaths and maintain healthy longevity, focusing on effective coverage and treatment of NCDs and reducing and managing the related disability.

Differential Susceptibility of Aedes aegypti and Aedes albopictus Mosquitoes to Infection by Mayaro Virus Strains.

Mayaro virus (MAYV) is an arthropod-borne virus (arbovirus) belonging to the family Togaviridae, genus Alphavirus. In recent years, the geographic distribution of MAYV may have expanded north from South and Central America into the Caribbean Islands. Although Haemagogus janthinomys is considered the main vector for MAYV, the virus has also been isolated from other mosquitoes, including Aedes aegypti, a widespread species that serves as the main vector for highly epidemic viruses. Given the possible expansion and outbreaks of MAYV in Latin America, it is possible that MAYV might be adapting to be efficiently transmitted by urban vectors. Therefore, to investigate this possibility, we evaluated the vector competence of Ae. aegypti and Ae. albopictus mosquitoes to transmit MAYV isolated during a year of low or high MAYV transmission. Adult Ae. aegypti and Ae. albopictus were orally infected with the MAYV strains, and the infection, dissemination, and transmission rates were calculated to evaluate their vector competence. Overall, we found higher infection, dissemination, and transmission rates in both Ae. aegypti and Ae. albopictus mosquitoes infected with the strain isolated during a MAYV outbreak, whereas low/no transmission was detected with the strain isolated during a year of low MAYV activity. Our results confirmed that both Ae. aegypti and Ae. albopictus are competent vectors for the emergent MAYV. Our data suggest that strains isolated during MAYV outbreaks might be better fit to infect and be transmitted by urban vectors, raising serious concern about the epidemic potential of MAYV.

Is there an association between inflammatory markers and lower physical performance in older adults?

BACKGROUND: Maintenance of physical performance is essential for achievement of healthy aging. A few studies have explored the association between inflammatory markers and physical performance in older adults with inconclusive results. Our aim was to analyze the association of tumor necrosis factor-alpha (TNF-α), Interleukin-10 (IL-10), and C-reactive protein (CRP) with physical performance in a sample of older adults in rural settings of Mexico. METHODS: Our study comprised 307 community-dwelling older men and women who participated in the third wave of the Rural Frailty Study. We assessed the physical performance with the Short Physical Performance Battery (SPPB) and classified older adults as low performance if SPPB scored ≤8. Inflammatory markers were ascertained using serum by immunodetection methods. Logistic regression models were used to estimate the associations between inflammatory markers and physical performance. RESULTS: In comparison with the normal physical performance group, low physical performance individuals mainly were female (P <  0.01), older (P <  0.01), more illiterate (P = 0.02), more hypertensive (P < 0.01), fewer smokers (P = 0.02), and had higher CRP levels (P < 0.01). The logistic model results showed a significant association between the 3rd tertile of CRP and low physical performance (OR = 2.23; P = 0.03). IL-10 and TNF-α levels did not show a significant association. CONCLUSIONS: The results of this study were mixed, with a significant association of physical performance with higher CRP levels but nonsignificant with IL-10 and TNF-α. Further studies with improved designs are needed by incorporating a broader set of inflammatory markers.

Assessing the Impact of Insecticide Resistance on Vector Competence: A Review.

The primary strategy to avoid adverse impacts from insect-mediated pathogen transmission is the chemical control of vector populations through insecticides; its continued use has led to insecticide resistance and unknown consequences on vector competence. This review aims to systematically analyze and synthesize the research on the influence of insecticide resistance (IR) on vector competence (VC). Thirty studies met the inclusion criteria. Twenty studies, conducted either in laboratory or field settings, described the influence of phenotypic insecticide resistance and mechanisms on VC in vectors of human pathogens. Seven studies showed the effect of exposure to insecticides on VC in vectors of human pathogens. Three studies reported the influence of phenotypic resistance and mechanisms on VC in crop pests. The evidence shows that IR could enhance, impair, or have no direct effect on VC in either field or laboratory-designed studies. Similar positive and negative trends are found in pest vectors in crops and studies of insecticide exposure and VC. Even though there is evidence that exposure to insecticides and IR can enhance VC, thus increasing the risk of pathogen transmission, more investigations are needed to confirm the observed patterns and what implications these factors could have in vector control programs.

Flavivirus vaccines: Virus-like particles and single-round infectious particles as promising alternatives.

The genus flavivirus of the Flaviridae family includes several human pathogens, like dengue, Zika, Japanese encephalitis, and yellow fever virus. These viruses continue to be a significant threat to human health. Vaccination remains the most useful approach to reduce the impact of flavivirus fever. However, currently available vaccines can induce severe side effects or have low effectiveness. An alternative is the use of recombinant vaccines, of which virus-like particles (VLP) and single-round infectious particles (SRIP) are of especial interest. VLP consist of the virus structural proteins produced in a heterologous system that self-assemble in a structure almost identical to the native virus. They are highly immunogenic and have been effective vaccines for other viruses for over 30 years. SRIP are promising vaccine candidates, as they induce both cellular and humoral responses, as viral proteins are expressed. Here, the state of the art to produce both types of particles and their use as vaccines against flaviviruses are discussed. We summarize the different approaches used for the design and production of flavivirus VLP and SRIP, the evidence for their safety and efficacy, and the main challenges for their use as commercial vaccines.

Monitoring Mitochondrial Function in Aedes albopictus C6/36 Cell Line during Dengue Virus Infection.

Aedes aegypti and Aedes albopictus mosquitoes are responsible for dengue virus (DENV) transmission in tropical and subtropical areas worldwide, where an estimated 3 billion people live at risk of DENV exposure. DENV-infected individuals show symptoms ranging from sub-clinical or mild to hemorrhagic fever. Infected mosquitoes do not show detectable signs of disease, even though the virus maintains a lifelong persistent infection. The interactions between viruses and host mitochondria are crucial for virus replication and pathogenicity. DENV infection in vertebrate cells modulates mitochondrial function and dynamics to facilitate viral proliferation. Here, we describe that DENV also regulates mitochondrial function and morphology in infected C6/36 mosquito cells (derived from Aedes albopictus). Our results showed that DENV infection increased ROS (reactive oxygen species) production, modulated mitochondrial transmembrane potential and induced changes in mitochondrial respiration. Furthermore, we offer the first evidence that DENV causes translocation of mitofusins to mitochondria in the C6/36 mosquito cell line. Another protein Drp-1 (Dynamin-related protein 1) did not localize to mitochondria in DENV-infected cells. This observation therefore ruled out the possibility that the abovementioned alterations in mitochondrial function are associated with mitochondrial fission. In summary, this report provides some key insights into the virus-mitochondria crosstalk in DENV infected mosquito cells.

Experimental infection and vector competence of Zika virus in Aedes aegypti mosquitoes from Acapulco, Guerrero, Mexico.

OBJECTIVE: To gain a better understanding of the Zika virus (ZIKV) vector transmission in Mexico, we determined the vector competence of a local population of Ae. aegypti (Acapulco, Guerrero) for a strain of ZIKV isolated from a Mexican febrile patient. MATERIALS AND METHODS: Eggs were hatched and larvae were reared under controlled conditions. After five days post-emergence, female mosquitoes were fed an infectious blood-meal containing ZIKV. Mosquitoes were analyzed at 4, 7 and 14-day post-infection (dpi). Infection (gut), dissemination (wings, legs and heads) and potential transmission (salivary glands) were assessed by RT-qPCR. The Rockefeller Ae. aegypti strain was used as ZIKV infection control. RESULTS: ZIKV infection, dissemination, and potential transmission rates were 96.2, 96.1 and 93.2%, respectively. CONCLUSIONS: Ae. aegypti (F1) from Acapulco were very susceptible to ZIKV infection, and showed similar vector competence to that of the susceptible Rockefeller strain. To our knowledge, this is the first report of vector competence for ZIKV performed in a Mexican laboratory.

OBJETIVO: Determinar la competencia vectorial de una población local de Ae. aegypti para transmitir el virus Zika (ZIKV) aislado de un paciente febril mexicano. MATERIAL Y MÉTODOS: Se desarrolló la primera generación (F1) de mosquitos Ae. aegypti en el insectario a partir de huevos colectados mediante ovitrampas en la Colonia Renacimiento, Acapulco, Guerrero. Después de cinco días de la emergencia, los mosquitos hembras fueron alimentados con sangre infecciosa con ZIKV. La infección (intestino), la diseminación (alas, piernas y cabezas) y la transmisión potencial (glándulas salivales) se evaluaron mediante RT-qPCR, a los 4, 7 y 14 días después de la alimentación. RESULTADOS: La infección por ZIKV, la diseminación y las tasas potenciales de transmisión fueron de 96.2, 96.1 y 93.2%, respectivamente. CONCLUSIONES: Los mosquitos Ae. aegypti (F1) de Acapulco presentan una alta competencia vectorial (93.2%). Según los autores de este estudio, este es el primer informe de competencia vectorial para ZIKV realizado en un laboratorio mexicano.

Experimental infection and vector competence of Zika virus in Aedes aegypti mosquitoes from Acapulco, Guerrero, Mexico / Infección experimental y competencia vectorial del virus Zika en mosquitos Aedes aegypti de Acapulco, Guerrero, México

Abstract: Objective: To gain a better understanding of the Zika virus (ZIKV) vector transmission in Mexico, we determined the vector competence of a local population ofAe. aegypti(Acapulco, Guerrero) for a strain of ZIKV isolated from a Mexican febrile patient. Materials and methods: Eggs were hatched and larvae were reared under controlled conditions. After five days post-emergence, female mosquitoes were fed an infectious blood-meal containing ZIKV. Mosquitoes were analyzed at 4, 7 and 14-day post-infection (dpi). Infection (gut), dissemination (wings, legs and heads) and potential transmission (salivary glands) were assessed by RT-qPCR. The RockefellerAe. aegyptistrain was used as ZIKV infection control. Results: ZIKV infection, dissemination, and potential transmission rates were 96.2, 96.1 and 93.2%, respectively. Conclusions: Ae. aegypti(F1) from Acapulco were very susceptible to ZIKV infection, and showed similar vector competence to that of the susceptible Rockefeller strain. To our knowledge, this is the first report of vector competence for ZIKV performed in a Mexican laboratory.

Resumen: Objetivo: Determinar la competencia vectorial de una población local deAe. aegyptipara transmitir el virus Zika (ZIKV) aislado de un paciente febril mexicano. Material y métodos: Se desarrolló la primera generación (F1) de mosquitosAe. aegyptien el insectario a partir de huevos colectados mediante ovitrampas en la Colonia Renacimiento, Acapulco, Guerrero. Después de cinco días de la emergencia, los mosquitos hembras fueron alimentados con sangre infecciosa con ZIKV. La infección (intestino), la diseminación (alas, piernas y cabezas) y la transmisión potencial (glándulas salivales) se evaluaron mediante RT-qPCR, a los 4, 7 y 14 días después de la alimentación. Resultados: La infección por ZIKV, la diseminación y las tasas potenciales de transmisión fueron de 96.2, 96.1 y 93.2%, respectivamente. Conclusiones: Los mosquitos Ae. aegypti (F1) de Acapulco presentan una alta competencia vectorial (93.2%). Según los autores de este estudio, este es el primer informe de competencia vectorial para ZIKV realizado en un laboratorio mexicano.

Quantitative proteomic analysis reveals high interference on protein expression of H9c2 cells activated with glucose and cardiotonic steroids.

In recent decades, the incidence of death and morbidity due to diabetes has increased worldwide, causing a high social and economic impact. Diabetes is a major cause of blindness, kidney failure, heart attack, stroke and lower limb amputation. However, the molecular mechanisms that make the heart and kidneys the main targets of diabetes are not completely understood. To better understand the complex biochemical mechanism of diabetic cardiomyopathy, we investigated the effects of hyperglycemia with concomitant digoxin and ouabain stimulation in H9c2 cells. Total extracted proteins were analyzed by label-free LC-MS/MS, quantified by Scaffold software and validated by parallel reaction monitoring (PRM) methodology. Here, we show that the eukaryotic initiation factors (Eifs) and elongation factors (Eefs) Eif3f, Eef2 and Eif4a1 are overexpressed following cardiotonic steroid (CTS) stimulation. Similarly, the expression of four 14-3-3 proteins that play a key role in cardiac ventricular compaction was altered after CTS stimulation. In total, the expression of nine protein groups was altered in response to the stimulation of H9c2 cells. Here, the biological consequences of these changes are discussed in depth. SIGNIFICANCE: Hyperglycemia is the main physiological condition that provokes tissue and vascular injuries in heart of diabetic patients. However, the changings at large scale in the expression of proteins of cardiomyocytes generated by this condition was not yet studied. Here we report for the first time the altered biosynthesis of nine groups of proteins of H9c2 cells activated by high glucose concentrations and by cardiotonic steroids (CTS). Furthermore, the increased biosynthesis of Eifs, Eefs and 14-3-3 protein groups by CTS, which play a crucial role in cardiomyopathies are original data reported in this work. These findings not only enhance our knowledge concerning to the effects of hyperglycemia and CTS on H9c2 cells but also indicate potential molecular targets to interfere in diabetes cardiomyopathy progression.

Antiviral and immunomodulatory effects of polyphenols on macrophages infected with dengue virus serotypes 2 and 3 enhanced or not with antibodies.

Background: There is a lack of specific antiviral therapy against dengue virus (DENV) in current use. Therefore, a great proportion of dengue cases progress to severe clinical forms due to a complex interplay between virus and host immune response. It has been hypothesized that heterotypic non-neutralizing antibodies enhance DENV infection in phagocytic cells, and this induces an inflammatory response that is involved in the pathogenesis of severe dengue. Purpose: To identify the antiviral and immunomodulatory effects of polyphenols on dengue virus infection. Methods: Human U937-DC-SIGN macrophages were infected with DENV serotypes 2 or 3 in the presence or not of enhancing antibody 4G2. Viral titers and the secretion of tumor necrosis factor-alpha, IL-6, IL-10 and interferon-alpha were analyzed timely. Results: DENV infection alone induced high production of IL-6 and TNF-α, but in the presence of 4G2 antibody, viral titers and TNF-α secretion were potentiated. Based on anti-inflammatory antecedents, the polyphenols curcumin, fisetin, resveratrol, apigenin, quercetin and rutin were tested for antiviral and immunomodulatory properties. Only quercetin and fisetin inhibited DENV-2 and DENV-3 infection in the absence or presence of enhancing antibody (>90%, p<0.001); they also inhibited TNF-α and IL-6 secretion (p<0.001). Conclusion: Quercetin and fisetin down-regulate the production of proinflammatory cytokines induced by DENV infection enhanced by antibodies a mechanism involved in severe dengue.

Author Correction: Zika Virus in Salivary Glands of Five Different Species of Wild-Caught Mosquitoes from Mexico.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

Zika Virus in Salivary Glands of Five Different Species of Wild-Caught Mosquitoes from Mexico.

Zika virus (ZIKV) is a mosquito-borne pathogen, and Aedes aegypti has been identified as the main vector of the disease. Other mosquito species in the Aedes and Culex genera have been suggested to have the potential for being competent vectors based on experimental exposition of mosquitoes to an infectious blood meal containing ZIKV. Here, we report the isolation in cell culture of ZIKV obtained from different body parts of wild-caught female mosquitoes (Ae. aegypti, Ae. vexans, Cx. quinquefasciatus, Cx. coronator, and Cx. tarsalis) and whole male mosquitoes (Ae. aegypti and Cx. quinquefasciatus) in Mexico. Importantly, this is the first report that shows the presence of the virus in the salivary glands of the wild-caught female mosquitoes species, Cx. coronator, Cx. tarsalis, and Ae. vexans. Our findings strongly suggest that all the species reported herein are potential vectors for ZIKV.

Corrigendum: Serum Metabolic Alterations upon Zika Infection.

[This corrects the article on p. 1954 in vol. 8, PMID: 29067015.].

Serum Metabolic Alterations upon Zika Infection.

Zika virus (ZIKV) infection has recently emerged as a major concern worldwide due to its strong association with nervous system malformation (microcephaly) of fetuses in pregnant women infected by the virus. Signs and symptoms of ZIKV infection are often mistaken with other common viral infections. Since transmission may occur through biological fluids exchange and coitus, in addition to mosquito bite, this condition is an important infectious disease. Thus, understanding the mechanism of viral infection has become an important research focus, as well as providing potential targets for assertive clinical diagnosis and quality screening for hemoderivatives. Within this context, the present work analyzed blood plasma from 79 subjects, divided as a control group and a ZIKV-infected group. Samples underwent direct-infusion mass spectrometry and statistical analysis, where eight markers related to the pathophysiological process of ZIKV infection were elected and characterized. Among these, Angiotensin (1-7) and Angiotensin I were upregulated under infection, showing an attempt to induce autophagy of the infected cells. However, this finding is concerning about hypertensive individuals under treatment with inhibitors of the Renin-Angiotensin System (RAS), which could reduce this response against the virus and exacerbate the symptoms of the infection. Moreover, one of the most abundant glycosphingolipids in the nervous tissue, Ganglioside GM2, was also elected in the present study as an infection biomarker. Considered an important pathogen receptor at membrane's outer layer, this finding represents the importance of gangliosides for ZIKV infection and its association with brain tropism. Furthermore, a series of phosphatidylinositols were also identified as biomarkers, implying a significant role of the PI3K-AKT-mTOR Pathway in this mechanism. Finally, these pathways may also be understood as potential targets to be considered in pharmacological intervention studies on ZIKV infection management.

Aedes-Borne Virus-Mosquito Interactions: Mass Spectrometry Strategies and Findings.

Aedes-borne viruses are responsible for high-impact neglected tropical diseases and unpredictable outbreaks such as the ongoing Zika epidemics. Aedes mosquitoes spread different arboviruses such as Dengue virus (DENV), Chikungunya virus (CHIKV), and Zika virus, among others, and are responsible for the continuous emergence and reemergence of these pathogens. These viruses have complex transmission cycles that include two hosts, namely the Aedes mosquito as a vector and susceptible vertebrate hosts. Human infection with arboviruses causes diseases that range from subclinical or mild to febrile diseases, encephalitis, and hemorrhagic fever. Infected mosquitoes do not show detectable signs of disease, even though the virus maintains a lifelong persistent infection. The infection of the Aedes mosquito by viruses involves a molecular crosstalk between cell and viral proteins. An understanding of how mosquito vectors and viruses interact is of fundamental interest, and it also offers novel perspectives for disease control. In recent years, mass spectrometry (MS)-based strategies in combination with bioinformatics have been successfully applied to identify and quantify global changes in cellular proteins, lipids, peptides, and metabolites in response to viral infection. Although the information about proteomics in the Aedes mosquito is limited, the information that has been reported can set up the basis for future studies. This review reflects how MS-based approaches have extended our understanding of Aedes mosquito biology and the development of DENV and CHIKV infection in the vector. Finally, this review discusses future challenges in the field.

A Comprehensive Proteomic Study of the Skin Secretions of the Frog Lithobates spectabilis.

Disulfide C-terminal loop fragments derived from AMPs and the presence of peptidases have been previously reported in the skin secretions of different amphibians. However, there are only a few studies on the identification of enzymes in frog skin secretion based on the primary structure of these proteins. Similarly, little data exist regarding the identification of disulfide C-terminal loops at large scale. Therefore, a comprehensive study on this issue certainly could bring in much more information for understanding this molecular process and its biochemical consequences. Thus, the aim of this work was to characterize the presence of disulfide C-terminal loop fragments of AMPs and identify the proteins and probable enzymes present in the completely unknown secretion contents of the frog Lithobates spectabilis. For this purpose, high-resolution mass spectrometry was applied to analyze the skin secretions processed by two different protocols: (1) using a cocktail of enzymatic inhibitors and 2) without any protease inhibitors, maintaining the solution for 2 hours at 10°C. Results from procedure-1, revealed 122 molecular masses, whereas procedure-2 permitted 253 different molecular masses to be identified. Fifty-nine peptides including 22 disulfide C-terminal loop-containing peptides were obtained following procedure-2. Polyacrylamide gel electrophoresis separation, tryptic digestion and LCMS/ MS were used for "de novo" sequencing of 111 different peptides and the unequivocal identification of fifteen proteins including at least three different peptidases. Additionally, it was possible to fully sequence eight peptides, including a ranatuerin-related peptide identified here as Spectabilin, that was subsequently chemically synthesized and showed high antibacterial, antiparasitic and cytotoxic activities.