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Modern insects have inhabited the earth for hundreds of millions of years, and part of their successful adaptation lies in their many reproductive strategies. Insect reproduction is linked to a high metabolic rate that provides viable eggs in a relatively short time. In this context, an accurate interplay between the endocrine system and the nutrients synthetized and metabolized is essential to produce healthy offspring. Lipids guarantee the metabolic energy needed for egg formation and represent the main energy source consumed during embryogenesis. Lipids availability is tightly regulated by a complex network of endocrine signals primarily controlled by the central nervous system (CNS) and associated endocrine glands, the corpora allata (CA) and corpora cardiaca (CC). This endocrine axis provides hormones and neuropeptides that significatively affect tissues closely involved in successful reproduction: the fat body, which is the metabolic center supplying the lipid resources and energy demanded in egg formation, and the ovaries, where the developing oocytes recruit lipids that will be used for optimal embryogenesis. The post-genomic era and the availability of modern experimental approaches have advanced our understanding of many processes involved in lipid homeostasis; therefore, it is crucial to integrate the findings of recent years into the knowledge already acquired in the last decades. The present chapter is devoted to reviewing major recent contributions made in elucidating the impact of the CNS/CA/CC-fat body-ovary axis on lipid metabolism in the context of insect reproduction, highlighting areas of fruitful research.
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The caterpillar Anticarsia gemmatalis (Lepidoptera: Noctuidae) is a prevalent pest in soybean plantations, managed using both natural and synthetic chemical products. However, the emergence of resistance in some populations emphasizes the need to explore alternative insecticides. Flupyradifurone, a neurotoxic insecticide, has not been previously used for controlling A. gemmatalis. This study evaluated the potential of flupyradifurone in the management of A. gemmatalis. Initially, the toxicity and anti-feeding effects, as well as histopathological and cytotoxic impacts, of flupyradifurone on A. gemmatalis were evaluated. Subsequently, the indirect effects of flupyradifurone on the midgut and fat body of the predator Podisus nigrispinus (Hemiptera: Pentatomidae) were verified. The results indicate the susceptibility of caterpillars to flupyradifurone, with an LC50 of 5.10 g L-1. Furthermore, the insecticide adversely affects survival, induces an anti-feeding response, and inflicts damage on the midgut of the caterpillars. However, flupyradifurone also leads to side effects in the predator P. nigrispinus through indirect intoxication of the caterpillars, including midgut and fat body damage. While flupyradifurone demonstrates toxicity to A. gemmatalis, suggesting its potential for the chemical control of this pest, the indirect negative effects on the predator indicate the need for its controlled use in integrated pest management programs with the insecticide and the predator.
Assuntos
Inseticidas , Animais , Inseticidas/toxicidade , Larva/efeitos dos fármacos , 4-Butirolactona/análogos & derivados , 4-Butirolactona/toxicidade , Heterópteros/efeitos dos fármacos , Mariposas/efeitos dos fármacos , Lepidópteros/efeitos dos fármacos , PiridinasRESUMO
A gordofobia caracteriza-se pela discriminação e patolo-gização do sujeito corpulento, ganhando intensidade pela veicu-lação midiática com discursos pautados nas ciências biomédicas que desconsideram individualidades e subjetividades. Este estudo tem como objetivo realizar um levantamento bibliográfico acerca desses discursos, entre 2002-2021, caracterizado como um estudo qualitativo do tipo Teoria do Estado do Conhecimento, com a bus-ca nas bases de dados do SciELO (2 artigos); BDTD (3 dissertações e 1 tese) e OASISBR (2 artigos). Evidenciou-se que os saberes do modelo biomédico (normalidade e patologia) nas discursividades midiáticas têm enaltecido o corpo magro como "ideal", enquanto o corpo gordo tem sido visto como doente, impondo-se culpabilida-de e estigmatização.
Fatphobia is characterized by discrimination and patho-logization of the corpulent subject, gaining intensity through me-dia coverage with discourses based on biomedical sciences that disregard individualities and subjectivities. This study aimed to car-ry out a bibliographical survey regarding these speeches, between 2002-2021, characterized as a qualitative study of the Theory of the State of Knowledge type, with a search in the SciELO databases (2 articles); Brazilian Digital Library of Theses and Dissertations - (BDTD) (3 dissertations and 1 thesis) and Brazilian Open Access Publications and Scientific Data Portal - (OASISBR) (2 articles). It was evident that the knowledge of the biomedical model (norma-lity and pathology) in the media discourse has praised the thin body as "ideal", while the fat body has been seen as sick, imposing guilt and stigmatization.
La gordofobia se caracteriza por la discriminación y pa-tologización del sujeto corpulento, cobrando intensidad a través de la divulgación mediática con discursos basados en las ciencias biomédicas que prescinden de individualidades y subjetividades. Este estudio tuvo como objetivo realizar un levantamiento biblio-gráfico sobre estos discursos, entre 2002-2021, caracterizado como un estudio cualitativo del tipo Teoría del Estado del Conocimiento, con búsqueda en las bases de datos SciELO (2 artículos); BDTD (3 disertaciones y 1 tesis) y OASISBR (2 artículos). Se evidenció que el conocimiento del modelo biomédico (normalidad y patología) en el discurso mediático ha elogiado el cuerpo delgado como "ideal", mientras que el cuerpo gordo ha sido visto como enfermo, impo-niendo culpa y estigmatización.
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A gordofobia caracteriza-se pela discriminação e patologização do sujeito corpulento, ganhando intensidade pela veiculação midiática com discursos pautados nas ciências biomédicas que desconsideram individualidades e subjetividades. Este estudo tem como objetivo realizar um levantamento bibliográfico acerca desses discursos, entre 2002-2021, caracterizado como um estudo qualitativo do tipo Teoria do Estado do Conhecimento, com a busca nas bases de dados do SciELO (2 artigos); BDTD (3 dissertações e 1 tese) e OASISBR (2 artigos). Evidenciou-se que os saberes do modelo biomédico (normalidade e patologia) nas discursividades midiáticas têm enaltecido o corpo magro como "ideal", enquanto o corpo gordo tem sido visto como doente, impondo-se culpabilidade e estigmatização (AU).
Fatphobia is characterized by discrimination and patho-logization of the corpulent subject, gaining intensity through me-dia coverage with discourses based on biomedical sciences that disregard individualities and subjectivities. This study aimed to car-ry out a bibliographical survey regarding these speeches, between 2002-2021, characterized as a qualitative study of the Theory of the State of Knowledge type, with a search in the SciELO databases (2 articles); Brazilian Digital Library of Theses and Dissertations - (BDTD) (3 dissertations and 1 thesis) and Brazilian Open Access Publications and Scientific Data Portal - (OASISBR) (2 articles). It was evident that the knowledge of the biomedical model (norma-lity and pathology) in the media discourse has praised the thin body as "ideal", while the fat body has been seen as sick, imposing guilt and stigmatization (AU).
La gordofobia se caracteriza por la discriminación y pa-tologización del sujeto corpulento, cobrando intensidad a través de la divulgación mediática con discursos basados en las ciencias biomédicas que prescinden de individualidades y subjetividades. Este estudio tuvo como objetivo realizar un levantamiento biblio-gráfico sobre estos discursos, entre 2002-2021, caracterizado como un estudio cualitativo del tipo Teoría del Estado del Conocimiento, con búsqueda en las bases de datos SciELO (2 artículos); BDTD (3 disertaciones y 1 tesis) y OASISBR (2 artículos). Se evidenció que el conocimiento del modelo biomédico (normalidad y patología) en el discurso mediático ha elogiado el cuerpo delgado como "ideal", mientras que el cuerpo gordo ha sido visto como enfermo, impo-niendo culpa y estigmatización (AU).
Assuntos
Humanos , Mídias SociaisRESUMO
Lipid storage in the form of triacylglycerol (TAG) is essential for insect life, as it enables flight, development, and reproduction. The activity of the lipase brummer (bmm) has been shown to be essential to insects' homeostasis. The objective of this study was to evaluate how bmm expression occurs in Aedes aegypti larvae and adults, and to observe TAG levels during fasting in adult females. The bmm sequence was identified in A. aegypti and exhibited a patatin-like phospholipase domain reinforced by the presence of a catalytic dyad with serine and aspartate residues, revealing a high degree of similarity with other organisms. Bmm expression was differentiated in the larvae and adult fat body (FB) following TAG reserve dynamics. Bmm was expressed three times in larval stages L3, L4, and pupae compared with L1 and L2, which could indicate its role in the maturation of these insects. In the postemergence (PE) and post-blood meal (PBM) FB of adult insects, bmm expression varied over several days. PE adults showed a pronounced bmm increase from the third day onward compared with those not subjected to fasting. This was accompanied by a decrease in TAG from the third day onward, suggesting the participation of bmm. Six hours after blood feeding, TAG levels increased in mosquitos reared in the absence of sucrose, suggesting lipid accumulation to guarantee reproduction. Bmm responded positively to fasting, followed by TAG mobilization in adult FB. During the previtellogenic period, bmm levels responded to low TAG levels, unlike the PBM period.
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Aedes , Feminino , Animais , Triglicerídeos/metabolismo , Lipase/metabolismo , Metabolismo dos Lipídeos , Larva , JejumRESUMO
ABSTRACT BACKGROUND: Research on the economic burden of sedentary behavior and abdominal obesity on health expenses associated with cardiovascular diseases is scarce. OBJECTIVE: The objective of this study was to verify whether sedentary behavior, isolated and combined with abdominal obesity, influences the medication expenditure among adults with cardiovascular diseases. DESIGN AND SETTING: This cross-sectional study was conducted in the city of President Prudente, State of São Paulo, Brazil in 2018. METHODS: The study included adults with cardiovascular diseases, aged 30-65 years, who were treated by the Brazilian National Health Services. Sedentary behavior was assessed using a questionnaire. Abdominal obesity was defined by waist circumference. Medication expenditures were verified using the medical records of each patient. RESULTS: The study included a total of 307 adults. Individuals classified in the group with risk factor obesity combined (median [IQ] USD$ 29.39 [45.77]) or isolated (median [IQ] USD$ 27.17 [59.76]) to sedentary behavior had higher medication expenditures than those belonging to the non-obese with low sedentary behavior group (median [IQ] USD$ 13.51 [31.42]) (P = 0.01). The group with combined obesity and sedentary behavior was 2.4 (95%CI = 1.00; 5.79) times more likely to be hypertensive. CONCLUSION: Abdominal obesity was a determining factor for medication expenses, regardless of sedentary behavior, among adults with cardiovascular diseases.
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During its life cycle, Trypanosoma rangeli invades the hemolymph of its invertebrate host and colonizes hemocytes and salivary glands. The parasite cannot synthesize some lipid classes, and during its cycle, it depends on the uptake of these molecules from its vertebrate and invertebrate hosts to meet growth and differentiation requirements. However, until now, knowledge on how the parasite affects the lipid physiology of individual insect organs has been largely unknown. Herein, the biochemical and molecular dynamics of triatomine R. prolixus lipid metabolism in response to acute T. rangeli infection were investigated. Biochemical and microscopic assays revealed the lipid droplet profile and the levels of the different identified lipid classes. In addition, a qRTâPCR approach was used to determine the expression profile of 6 protein-coding genes involved in the R. prolixus lipid physiology. We observed that triacylglycerol (TAG), monoacylglycerol (MAG), phosphatidylethanolamine (PE) and phosphatidylcholine (PC) levels in the fat body decreased in infected insects. On the other hand, high levels of free fatty acids were observed in the hemolymph during infection. Analysis by confocal microscopy revealed a decrease in lipid droplets size from infected fat bodies, and investigations by scanning electron microscopy revealed a significant number of parasites adhered to the surface of the organ. T. rangeli infection upregulated the transcript levels of the protein-coding gene for the acetyl-CoA carboxylase, the first enzyme in the de novo fatty acid synthesis pathway, responsible for the production of malonyl-CoA. On the other hand, downregulation of lipophorin receptor was observed. In conclusion, this study reveals a new set of molecular events that occur within the vector in response to the challenge imposed by the parasite.
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Rhodnius , Trypanosoma rangeli , Trypanosoma , Animais , Trypanosoma rangeli/genética , Rhodnius/parasitologia , Metabolismo dos Lipídeos , Glândulas Salivares/metabolismo , Lipídeos , Trypanosoma/genéticaRESUMO
Trypanosoma rangeli is a protozoan parasite that infects triatomines and mammals in the Americas, producing mixed infections with Trypanosoma cruzi, the etiological agent of Chagas disease. The former parasite is not pathogenic to humans, but has different levels of pathogenicity, as well as causing physiological and behavioral alterations, to its invertebrate hosts. In this study, we measured locomotory activity, and the glyceride accumulation profile in the hemolymph and fat body, as well as the expression of key genes related to triglyceride metabolism, of Rhodnius prolixus nymphs infected with T. rangeli. We found that the locomotory activity of the insects was correlated with the amount of triglycerides in the fat body. Infected nymphs had increased activity when starved, and also had an accumulation of glycerides in the fat body and hemolymph. These alterations were also associated with a higher expression of the diacylglycerol acyltransferase, lipophorin and lipophorin receptor genes in the fat body. We infer that T. rangeli is able to alter the energetic processes of its invertebrate host, in order to increase the availability of lipids to the parasite, which, in turn modifies the activity levels of the insect. These alterations are discussed with regard to their potential to increase the transmission rate of the parasite.
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Rhodnius , Trypanosoma rangeli , Humanos , Animais , Trypanosoma rangeli/fisiologia , Rhodnius/genética , Interações Hospedeiro-Parasita , Insetos Vetores/fisiologia , Ninfa , Metabolismo Energético , MamíferosRESUMO
ABSTRACT BACKGROUND: Identifying the relationship between maximum consumption of oxygen and body fat percentage is important due to increased cardiovascular risk factors. OBJECTIVE: This study aimed to verify the association between body fat percentage determined by three predictive equations using anthropometric measures (Lohman, Boileau, and Slaughter) and maximum oxygen uptake (VO2max). We also aimed to estimate the capacity of these equations for explaining VO2max variations in adolescents according to sex. DESIGN AND SETTING: This was a cross-sectional study conducted in high schools in São José, Southern Brazil. METHODS: This study included 879 adolescents (14-19 years) from Southern Brazil. Aerobic fitness was assessed using the modified Canadian Aerobic Fitness Test. The independent variable was body fat percentage predicted by the Lohman, Boileau, and Slaughter equations. Analyses adjusted for sociodemographic variables, physical activity level, and sexual maturation were performed with P value < 0.05. RESULTS: All anthropometric prediction equations used to estimate body fat percentage explained VO2max variations in adolescents. In male adolescents, both regression models based on the Boileau et al.12 and Lohman10 equations revealed higher explanatory power for VO2max (20%) compared with that based on the Slaughter et al.13 equation (19%). In female adolescents, the model based on the anthropometric equation of Slaughter et al.13 showed the greatest explanatory power for VO2max (18%). CONCLUSION: The inverse relationship between VO2max and body fat intensifies the need for effective intervention programs that prioritize maintenance of appropriate body fat and aerobic fitness levels because inadequate levels of both factors result in negative health consequences.
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BACKGROUND: Lipid homeostasis is an evolutionarily conserved process that is crucial for energy production, storage and consumption. Drosophila larvae feed continuously to achieve the roughly 200-fold increase in size and accumulate sufficient reserves to provide all energy and nutrients necessary for the development of the adult fly. The mechanisms controlling this metabolic program are poorly understood. RESULTS: Herein we identified a highly conserved gene, orsai (osi), as a key player in lipid metabolism in Drosophila. Lack of osi function in the larval fat body, the regulatory hub of lipid homeostasis, reduces lipid reserves and energy output, evidenced by decreased ATP production and increased ROS levels. Metabolic defects due to reduced Orsai (Osi) in time trigger defective food-seeking behavior and lethality. Further, we demonstrate that downregulation of Lipase 3, a fat body-specific lipase involved in lipid catabolism in response to starvation, rescues the reduced lipid droplet size associated with defective orsai. Finally, we show that osi-related phenotypes are rescued through the expression of its human ortholog ETFRF1/LYRm5, known to modulate the entry of ß-oxidation products into the electron transport chain; moreover, knocking down electron transport flavoproteins EtfQ0 and walrus/ETFA rescues osi-related phenotypes, further supporting this mode of action. CONCLUSIONS: These findings suggest that Osi may act in concert with the ETF complex to coordinate lipid homeostasis in the fat body in response to stage-specific demands, supporting cellular functions that in turn result in an adaptive behavioral response.
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Proteínas de Drosophila , Drosophila melanogaster , Metabolismo dos Lipídeos , Animais , Humanos , Trifosfato de Adenosina/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Corpo Adiposo/metabolismo , Flavoproteínas/metabolismo , Larva , Lipase/genética , Lipase/metabolismo , Metabolismo dos Lipídeos/genética , Lipídeos , Espécies Reativas de Oxigênio/metabolismoRESUMO
BACKGROUND: Low bone mineral density (BMD) is common in patients with inflammatory bowel disease. However, nutritional risk factors for low BMD in the ulcerative colitis (UC) population are still poorly understood. AIM: To investigate the association of anthropometric indicators and body composition with BMD in patients with UC. METHODS: This is a cross-sectional study on adult UC patients of both genders who were followed on an outpatient basis. A control group consisting of healthy volunteers, family members, and close people was also included. The nutritional indicators evaluated were body mass index (BMI), total body mass (TBM), waist circumference (WC), body fat in kg (BFkg), body fat in percentage (BF%), trunk BF (TBF), and also lean mass. Body composition and BMD assessments were performed by dual-energy X-ray absorptiometry. RESULTS: The sociodemographic characteristics of patients with UC (n = 68) were similar to those of healthy volunteers (n = 66) (P > 0.05). Most patients (97.0%) were in remission of the disease, 58.8% were eutrophic, 33.8% were overweight, 39.0% had high WC, and 67.6% had excess BF%. However, mean BMI, WC, BFkg, and TBF of UC patients were lower when compared to those of the control group (P < 0.05). Reduced BMD was present in 41.2% of patients with UC (38.2% with osteopenia and 2.9% with osteoporosis) and 3.0% in the control group (P < 0.001). UC patients with low BMD had lower BMI, TBM, and BFkg values than those with normal BMD (P < 0.05). Male patients were more likely to have low BMD (prevalence ratio [PR] = 1.86; 95% confidence interval [CI]: 1.07-3.26). Those with excess weight (PR = 0.43; 95%CI: 0.19-0.97) and high WC (PR = 0.44; 95%CI: 0.21-0.94) were less likely to have low BMD. CONCLUSION: Patients with UC in remission have a high prevalence of metabolic bone diseases. Body fat appears to protect against the development of low BMD in these patients.
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Lipophorin is a major hemolymph lipoprotein found in insects with a molecular native mass of 700 kDa. In mosquitoes, two different types of apolipoproteins are characterized, apolipophorin-I (ApoLp-I, ~250 kDa) and apolipophorin-II (ApoLp-II, ~80 kDa). This concentration depends on the stage of development and the age of the insects. Lipophorins are best studied in mosquitoes of the genus Aedes and Anopheles. In this study, we analyze the lipophorin sequence and show the lipophorin purification of the Culex quinquefasciatus and the transcriptional profile of the lipophorin gene in different life cycle stages. Similar amino acid composition and molecular weights are founded in three mosquitoes species lipophorins amino acid sequence. The two subunits of purified lipophorin (Apo I and Apo II) showed molecular masses of approximately 248 and 93 kDa, like that found in other mosquitoes. A gradual increase in the lipophorin expression gene was obtained during the previtellogenic period and after feeding we obtained peak expression at 24 h after feeding. With our results, we conclude that C. quinquefasciatus protein sequence has the same characteristics as those observed in other mosquitoes and that the expression of its apolipophorins is induced by blood feeding.
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Aedes , Culex , Animais , Culex/genética , Lipoproteínas/química , Lipoproteínas/genética , Aedes/metabolismo , Sequência de AminoácidosRESUMO
Rhodnius prolixus is a hematophagous insect, vector of Chagas disease. After feeding, as blood is slowly digested, amino acids are used as substrates to fuel lipid synthesis, and adult females accumulate lipids in the fat body and produce eggs. In order to evaluate the importance of de novo fatty acid synthesis for this insect metabolism, we generated acetyl-CoA carboxylase (ACC) deficient insects. The knockdown (AccKD) females had delayed blood digestion and a shorter lifespan. Their fat bodies showed reduced de novo lipogenesis activity, did not accumulate triacylglycerol during the days after blood meal, and had smaller lipid droplets. At 10 days after feeding, there was a general decrease in the amounts of neutral lipids and phospholipids in the fat body. In the hemolymph, no difference was observed in lipid composition at 5 days after blood meal, but at day ten, there was an increase in hydrocarbon content and a decrease in phospholipids. Total protein concentration and amino acid composition were not affected. The AccKD females laid 60% fewer eggs than the control ones, and only 7% hatched (89% for control), although their total protein and triacylglycerol contents were not different. Scanning electron microscopy of the egg surface showed that chorion (eggshell) from the eggs laid by the AccKD insects had an altered ultrastructural pattern when compared to control ones. These results show that ACC has a central role in R. prolixus nutrient homeostasis, and its appropriate activity is important to digestion, lipid synthesis and storage, and reproductive success.
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Chagas disease is potentially life-threatening and caused by the protozoan parasite Trypanosoma cruzi. The parasite cannot synthesize some lipids and depends on the uptake of these lipids from its vertebrate and invertebrate hosts. To achieve this, T. cruzi may need to modify the physiology of the insect host for its own benefit. In this study, we investigated the interaction of T. cruzi (Y strain) with its insect vector Rhodnius prolixus and how it manipulates the vector lipid metabolism. We observed a physiological change in lipid flux in of infected insects. In the fat body of infected insects, triacylglycerol levels decreased by 80.6% and lipid storage droplet-1(LSD-1) mRNA levels were lower, when compared to controls. Lipid sequestration by infected midguts led to increased levels of 5' AMP-activated protein kinase (AMPK) phosphorylation and activation in the fat body, inhibiting the synthesis of fatty acids and stimulating their oxidation. This led to reduced lipid levels in the fat body of infected insets, despite the fact that T. cruzi does not colonize this tissue. There was a 3-fold increase, in lipid uptake and synthesis in the midgut of infected insects. Finally, our results suggest that the parasite modifies the lipid flux and metabolism of its vector R. prolixus through the increase in lipid delivery from the fat body to midgut that are then scavenge by T cruzi.
Assuntos
Doença de Chagas , Rhodnius , Trypanosoma cruzi , Animais , Doença de Chagas/parasitologia , Metabolismo dos Lipídeos , Fosfolipídeos/metabolismo , Rhodnius/parasitologia , Trypanosoma cruzi/fisiologiaRESUMO
Within the context of climate change, winter temperatures at high latitudes are predicted to rise faster than summer temperatures. This phenomenon is expected to negatively affect the diapause performance and survival of insects, since they largely rely on low temperatures to lower their metabolism and preserve energy. However, some insects like honeybees, remain relatively active during the winter and elevate their metabolic rate to produce endothermic heat when temperatures drop. Warming winters are thus expected to improve overwintering performance of honeybees. In order to verify this hypothesis, for two consecutive years, we exposed honeybee colonies to either a mild or cold winter. We then monitored the influence of wintering conditions on several parameters of honeybee overwintering physiology, such as levels of the cryoprotectant glycerol, expression levels of immune and antioxidant genes, and genes encoding multifunctional proteins, including vitellogenin, which promotes bee longevity. Winter conditions had no effect on the expression of antioxidant genes, and genes related to immunity were not consistently affected. However, mild winters were consistently associated with a lower investment in glycerol synthesis and a higher expression of fat body genes, especially apidaecin and vitellogenin. Finally, while we found that viral loads generally decreased through the winter, this trend was more pronounced under mild winter conditions. In conclusion, and without considering how warming temperatures might affect other aspects of honeybee biology before overwintering, our data suggest that warming temperatures will likely benefit honeybee vitality by notably reducing their viral loads over the winter.
Assuntos
Viroses , Vitelogeninas , Animais , Abelhas , Glicerol , Estações do Ano , Temperatura , Vitelogeninas/genéticaRESUMO
Rhodnius prolixus is an obligatory hematophagous insect, vector of Chagas disease. After blood meal, lipids are absorbed, metabolized, synthesized, and accumulated in the fat body. When necessary, stored lipids are mobilized, transported to other organs, or are oxidized to provide energy. Mitochondrial ß-oxidation is a cyclic conserved pathway, where degradation of long-chain fatty acids occurs to contribute to cellular energetic demands. Three of its reactions are catalyzed by the mitochondrial trifunctional protein (MTP), which is composed by hydroxyacyl-CoA dehydrogenase trifunctional multienzyme complex subunits alpha and beta (HADHA and HADHB, respectively). Here, we investigated the role of HADHA in lipid metabolism and reproduction of Rhodnius prolixus females. The expression of HADHA gene (RhoprHadha) was determined in the organs of starving adult insects. The flight muscle and ovary had higher expression levels when compared to the anterior and posterior midguts or the fat body. RhoprHadha gene expression was upregulated by blood meal in the flight muscle and fat body. We generated insects with RNAi-mediated knockdown of RhoprHadha to address the physiological role of this gene. RhoprHadha deficiency resulted in higher triacylglycerol content and larger lipid droplets in the fat body during starvation. After feeding, lifespan of the knockdown females was not affected, but they exhibited a decrease in oviposition, although hatching was the same in both groups. Silenced females showed lower forced flight capacity than the control ones, and their fat bodies had lower gene expression levels of Brummer lipase (RhoprBmm) and long-chain acyl-CoA synthetase 2 (RhoprAcsl2). Taken together, these findings indicate that HADHA is important to guarantee successful reproduction and efficient mobilization of lipid stores during starvation and flight.
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Serine protease inhibitors (serpins), a superfamily of protease inhibitors, are known to be involved in several physiological processes, such as development, metamorphosis, and innate immunity. In our study, a full-length serpin cDNA, designated Haserpin1, was isolated from the cotton bollworm Helicoverpa armigera. The cDNA sequence of Haserpin1 is 1176 nt long, with an open reading frame encoding 391 amino acids; there is one exon and no intron. The predicted molecular weight of Haserpin1 is 43.53 kDa, with an isoelectric point of 4.98. InterProScan was employed for Haserpin1 functional characterization, which revealed that Haserpin1 contains highly conserved signature motifs, including a reactive center loop (RCL) with a hinge region (E341N350), the serpin signature, (F367F375) and a predicted P1P1 cleavage site (L357S358), which are useful for identifying serpins. Transcripts of Haserpin1 were constitutively expressed in the fat body, suggesting that it is the major site for serpin synthesis. During the developmental stages, a fluctuation in the expression level of Haserpin1 was observed, with low expression detected at the 5th-instar larval stage. In contrast, relatively high expression was detected at the prepupal stage, suggesting that Haserpin1 might play a critical role at the H. armigera wandering stage. Although the detailed function of this serpin (Haserpin1) needs to be elucidated, our study provides a perspective for the functional investigation of serine protease inhibitor genes.(AU)
Sabe-se que os inibidores de serina protease (serpinas), uma superfamília de inibidores de protease, estão envolvidos em vários processos fisiológicos, como desenvolvimento, metamorfose e imunidade inata. Neste estudo, um cDNA de serpina de comprimento total, denominado Haserpin1, foi isolado da lagarta Helicoverpa armigera na cultura de algodão. A sequência de ADNc de Haserpin1 tem 1.176 nt de comprimento, com uma grelha de leitura aberta que codifica 391 aminoácidos; existe um éxon, mas nenhum íntron. O peso molecular previsto de Haserpin1 é de 43,53 kDa, com um ponto isoelétrico de 4,98. O InterProScan foi empregado para a caracterização funcional do Haserpin1, que revelou que o Haserpin1 contém motivos de assinatura altamente conservados, incluindo um loop central reativo (RCL) com uma região de dobradiça (E341-N350), a assinatura da serpina (F367-F375) e um local de clivagem previsto de P1-P1' (L357-S358), que são úteis para identificar serpinas. As transcrições de Haserpin1 foram expressas constitutivamente no corpo gordo, sugerindo que é o principal local para a síntese de serpinas. Durante os estágios de desenvolvimento, observou-se uma flutuação no nível de expressão de Haserpin1, com baixa expressão detectada no estágio larval do 5º ínstar. Por outro lado, detectou-se uma expressão relativamente alta no estágio pré-pupal, sugerindo que o Haserpin1 pode desempenhar um papel crítico no estágio errante de H. armigera. Embora a função detalhada dessa serpina (Haserpin1) precise ser elucidada, este estudo fornece uma perspectiva para a investigação funcional dos genes inibidores da serina protease.(AU)
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Gossypium/parasitologia , Pragas da Agricultura , Lepidópteros , Inibidores de Serina ProteinaseRESUMO
Abstract Serine protease inhibitors (serpins), a superfamily of protease inhibitors, are known to be involved in several physiological processes, such as development, metamorphosis, and innate immunity. In our study, a full-length serpin cDNA, designated Haserpin1, was isolated from the cotton bollworm Helicoverpa armigera. The cDNA sequence of Haserpin1 is 1176 nt long, with an open reading frame encoding 391 amino acids; there is one exon and no intron. The predicted molecular weight of Haserpin1 is 43.53 kDa, with an isoelectric point of 4.98. InterProScan was employed for Haserpin1 functional characterization, which revealed that Haserpin1 contains highly conserved signature motifs, including a reactive center loop (RCL) with a hinge region (E341-N350), the serpin signature, (F367-F375) and a predicted P1-P1′ cleavage site (L357-S358), which are useful for identifying serpins. Transcripts of Haserpin1 were constitutively expressed in the fat body, suggesting that it is the major site for serpin synthesis. During the developmental stages, a fluctuation in the expression level of Haserpin1 was observed, with low expression detected at the 5th-instar larval stage. In contrast, relatively high expression was detected at the prepupal stage, suggesting that Haserpin1 might play a critical role at the H. armigera wandering stage. Although the detailed function of this serpin (Haserpin1) needs to be elucidated, our study provides a perspective for the functional investigation of serine protease inhibitor genes.
Resumo Sabe-se que os inibidores de serina protease (serpinas), uma superfamília de inibidores de protease, estão envolvidos em vários processos fisiológicos, como desenvolvimento, metamorfose e imunidade inata. Neste estudo, um cDNA de serpina de comprimento total, denominado Haserpin1, foi isolado da lagarta Helicoverpa armigera na cultura de algodão. A sequência de ADNc de Haserpin1 tem 1.176 nt de comprimento, com uma grelha de leitura aberta que codifica 391 aminoácidos; existe um éxon, mas nenhum íntron. O peso molecular previsto de Haserpin1 é de 43,53 kDa, com um ponto isoelétrico de 4,98. O InterProScan foi empregado para a caracterização funcional do Haserpin1, que revelou que o Haserpin1 contém motivos de assinatura altamente conservados, incluindo um loop central reativo (RCL) com uma região de dobradiça (E341-N350), a assinatura da serpina (F367-F375) e um local de clivagem previsto de P1-P1' (L357-S358), que são úteis para identificar serpinas. As transcrições de Haserpin1 foram expressas constitutivamente no corpo gordo, sugerindo que é o principal local para a síntese de serpinas. Durante os estágios de desenvolvimento, observou-se uma flutuação no nível de expressão de Haserpin1, com baixa expressão detectada no estágio larval do 5º ínstar. Por outro lado, detectou-se uma expressão relativamente alta no estágio pré-pupal, sugerindo que o Haserpin1 pode desempenhar um papel crítico no estágio errante de H. armigera. Embora a função detalhada dessa serpina (Haserpin1) precise ser elucidada, este estudo fornece uma perspectiva para a investigação funcional dos genes inibidores da serina protease.
Assuntos
Animais , Serpinas/genética , Lepidópteros/genética , Mariposas/genética , Inibidores de Serina Proteinase/genética , Sequência de Aminoácidos , Larva/genéticaRESUMO
ABSTRACT Introduction: Aerobic exercise has begun to be widely recognized as a reasonable means of preventing fat and losing weight. Scholars have confirmed that sports can help the human body lose weight and lose fat. Objective: This article measures the exercise performance indicators of subjects in different body fat percentage groups and studies the relationship between body fat percentage and exercise performance indicators. Methods: The study uses experimental methods to determine the percentage of body fat of the subjects. After physical exercise and aerobic exercise, the volunteers were tested for aerobic capacity indicators. Results: The body fat percentage of physically inactive persons was negatively correlated with aerobic and anaerobic exercise capacity indexes. Conclusion: The mechanism of aerobic exercise in weight loss treatment has the effect of promoting lipolysis and regulating blood lipid metabolism. At the same time, it has a significant influence on the number and activity of fat cells. Level of evidence II; Therapeutic studies - investigation of treatment results.
RESUMO Introdução: O exercício aeróbico tem sido amplamente reconhecido como uma maneira racional de prevenir a gordura e perder peso. Pesquisadores confirmam que o esporte pode ajudar o corpo humano a perder peso e gordura. Objetivo: Este artigo mede indicadores de desempenho em exercícios praticados por indivíduos em grupos de porcentagem de gordura corporal diferentes e estuda a relação entre a porcentagem de gordura corporal e indicadores de desempenho em exercícios. Métodos: O estudo usa métodos experimentais para determinar a porcentagem de gordura corporal dos indivíduos. Após o exercício físico e aeróbico, os voluntários foram testados para indicadores de capacidade aeróbica. Resultados: A porcentagem de gordura corporal de pessoas fisicamente inativas está negativamente correlacionada aos índices de capacidade de exercícios aeróbico e anaeróbico. Conclusão: O mecanismo de exercícios aeróbicos no tratamento de perda de peso promove a lipólise e regula o metabolismo lipídico sanguíneo. Concomitantemente, influencia significativamente o número e a atividade de células gordurosas. Nível de evidência II; Estudos terapêuticos - investigação de resultados de tratamento.
RESUMEN Introducción: El ejercicio aeróbico ha sido ampliamente reconocido como una manera racional de prevenir la grasa y perder peso. Investigadores confirman que el deporte puede ayudar el cuerpo humano a perder peso y grasa. Objetivo: Este artículo mide indicadores de rendimiento en ejercicios practicados por individuos en grupos de porcentaje de grasa corporal e indicadores de rendimiento en ejercicios. Métodos: El estudio usa métodos experimentales para determinar el porcentaje de grasa corporal de los individuos. Tras el ejercicio físico y aeróbico, se testó los voluntarios para indicadores de capacidad aeróbica. Resultados: El porcentaje de grasa corporal de personas físicamente inactivas está negativamente correlacionado a los índices de capacidad de ejercicios aeróbico y anaeróbico. Conclusión: El mecanismo de ejercicios aeróbicos en el tratamiento de pérdida de peso promueve la lipolisis y regula el metabolismo lipídico sanguíneo. Simultáneamente, influencia significativamente el número y la actividad de células grasas. Nivel de evidencia II; Estudios terapéuticos - investigación de resultados de tratamiento.
RESUMO
Insects are unable to synthesize cholesterol and depend on the presence of sterols in the diet for cell membrane composition and hormone production. Thus, cholesterol absorption, transport, and metabolism are potential targets for vector and pest control strategies. Here, we investigate the dietary cholesterol absorption and tissue distribution in the kissing bug Rhodnius prolixus using radiolabeled cholesterol. Both the anterior and posterior midguts absorbed cholesterol from the ingested blood, although the anterior midgut absorbed more. We also observed esterified cholesterol labeling in the epithelium, indicating that midgut cells can metabolize and store cholesterol. Only a small amount of labeled cholesterol was found in the hemolymph, where it was mainly in the free form and associated with lipophorin (Lp). The fat body transiently accumulated cholesterol, showing a labeled cholesterol peak on the fifth day after the blood meal. The ovaries also incorporated cholesterol, but cumulatively. The insects did not absorb almost half of the ingested labeled cholesterol, and radioactivity was present in the feces. After injection of 3H-cholesterol-labeled Lp into females, a half-life of 5.5 ± 0.7 h in the hemolymph was determined. Both the fat body and ovaries incorporated Lp-associated cholesterol, which was inhibited at low temperature, indicating the participation of active cholesterol transport. These results help describe an unexplored part of R. prolixus lipid metabolism.