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Girotti JR, Calderón-Fernández GM. Lipid Metabolism in Insect Vectors of Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024. [PMID: 38954247 DOI: 10.1007/5584_2024_811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2024]
Abstract
According to the World Health Organization vector-borne diseases account for more than 17% of all infectious diseases, causing more than 700,000 deaths annually. Vectors are organisms that are able to transmit infectious pathogens between humans, or from animals to humans. Many of these vectors are hematophagous insects, which ingest the pathogen from an infected host during a blood meal, and later transmit it into a new host. Malaria, dengue, African trypanosomiasis, yellow fever, leishmaniasis, Chagas disease, and many others are examples of diseases transmitted by insects.Both the diet and the infection with pathogens trigger changes in many metabolic pathways, including lipid metabolism, compared to other insects. Blood contains mostly proteins and is very poor in lipids and carbohydrates. Thus, hematophagous insects attempt to efficiently digest and absorb diet lipids and also rely on a large de novo lipid biosynthesis based on utilization of proteins and carbohydrates as carbon source. Blood meal triggers essential physiological processes as molting, excretion, and oogenesis; therefore, lipid metabolism and utilization of lipid storage should be finely synchronized and regulated regarding that, in order to provide the necessary energy source for these events. Also, pathogens have evolved mechanisms to hijack essential lipids from the insect host by interfering in the biosynthesis, catabolism, and transport of lipids, which pose challenges to reproduction, survival, fitness, and other insect traits.In this chapter, we have tried to collect and highlight the current knowledge and recent discoveries on the metabolism of lipids in insect vectors of diseases related to the hematophagous diet and pathogen infection.
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Affiliation(s)
- Juan R Girotti
- Instituto de Investigaciones Bioquímicas de La Plata (CONICET-UNLP), Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina.
| | - Gustavo M Calderón-Fernández
- Instituto de Investigaciones Bioquímicas de La Plata (CONICET-UNLP), Facultad de Ciencias Médicas, Universidad Nacional de La Plata, La Plata, Argentina.
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Santos-Araujo S, Gomes F, Carvalho-Kelly LF, Meyer-Fernandes JR, Gondim KC, Ramos I. In the fed state, autophagy plays a crucial role in assisting the insect vector Rhodnius prolixus mobilize TAG reserves under forced flight activity. Front Physiol 2024; 15:1352766. [PMID: 38725570 PMCID: PMC11079428 DOI: 10.3389/fphys.2024.1352766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 02/09/2024] [Indexed: 05/12/2024] Open
Abstract
Autophagy is a cellular degradation pathway mediated by highly conserved autophagy-related genes (Atgs). In our previous work, we showed that inhibiting autophagy under starvation conditions leads to significant physiological changes in the insect vector of Chagas disease Rhodnius prolixus; these changes include triacylglycerol (TAG) retention in the fat body, reduced survival and impaired locomotion and flight capabilities. Herein, because it is known that autophagy can be modulated in response to various stimuli, we further investigated the role of autophagy in the fed state, following blood feeding. Interestingly, the primary indicator for the presence of autophagosomes, the lipidated form of Atg8 (Atg8-II), displayed 20%-50% higher autophagic activation in the first 2 weeks after feeding compared to the third week when digestion was complete. Despite the elevated detection of autophagosomes, RNAi-mediated suppression of RpAtg6 and RpAtg8 did not cause substantial changes in TAG or protein levels in the fat body or the flight muscle during blood digestion. We also found that knockdown of RpAtg6 and RpAtg8 led to modest modulations in the gene expression of essential enzymes involved in lipid metabolism and did not significantly stimulate the expression of the chaperones BiP and PDI, which are the main effectors of the unfolded protein response. These findings indicate that impaired autophagy leads to slight disturbances in lipid metabolism and general cell proteostasis. However, the ability of insects to fly during forced flight until exhaustion was reduced by 60% after knockdown of RpAtg6 and RpAtg8. This change was accompanied by TAG and protein increases as well as decreased ATP levels in the fat body and flight muscle, indicating that autophagy during digestion, i.e., under fed conditions, is necessary to sustain high-performance activity.
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Affiliation(s)
- Samara Santos-Araujo
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Fabio Gomes
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | | | | | - Katia C. Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Isabela Ramos
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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Arêdes DS, Rios T, Carvalho-Kelly LF, Braz V, Araripe LO, Bruno RV, Meyer-Fernandes JR, Ramos I, Gondim KC. Deficiency of Brummer lipase disturbs lipid mobilization and locomotion, and impairs reproduction due to defects in the eggshell ultrastructure in the insect vector Rhodnius prolixus. Biochim Biophys Acta Mol Cell Biol Lipids 2024; 1869:159442. [PMID: 38042331 DOI: 10.1016/j.bbalip.2023.159442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 11/27/2023] [Accepted: 11/29/2023] [Indexed: 12/04/2023]
Abstract
Rhodnius prolixus is a hematophagous insect, which feeds on large and infrequent blood meals, and is a vector of trypanosomatids that cause Chagas disease. After feeding, lipids derived from blood meal are stored in the fat body as triacylglycerol, which is recruited under conditions of energy demand by lipolysis, where the first step is catalyzed by the Brummer lipase (Bmm), whose orthologue in mammals is the adipose triglyceride lipase (ATGL). Here, we investigated the roles of Bmm in adult Rhodnius prolixus under starvation, and after feeding. Its gene (RhoprBmm) was expressed in all the analyzed insect organs, and its transcript levels in the fat body were not altered by nutritional status. RNAi-mediated knockdown of RhoprBmm caused triacylglycerol retention in the fat body during starvation, resulting in larger lipid droplets and lower ATP levels compared to control females. The silenced females showed decreased flight capacity and locomotor activity. When RhoprBmm knockdown occurred before the blood meal and the insects were fed, the females laid fewer eggs, which collapsed and showed low hatching rates. Their hemolymph had reduced diacylglycerol content and vitellogenin concentration. The chorion (eggshell) of their eggs had no difference in hydrocarbon amounts or in dityrosine crosslinking levels compared to control eggs. However, it showed ultrastructural defects. These results demonstrated that Bmm activity is important not only to guarantee lipid mobilization to maintain energy homeostasis during starvation, but also for the production of viable eggs after a blood meal, by somehow contributing to the right formation of the egg chorion.
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Affiliation(s)
- Daniela Saar Arêdes
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Thamara Rios
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Valdir Braz
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Luciana O Araripe
- Laboratório de Biologia Molecular de Insetos, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular - INCT-EM/CNPq, Brazil
| | - Rafaela V Bruno
- Laboratório de Biologia Molecular de Insetos, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular - INCT-EM/CNPq, Brazil
| | - José Roberto Meyer-Fernandes
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Biologia Estrutural e Bioimagem - INCT-BEB/CNPq, Brazil
| | - Isabela Ramos
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular - INCT-EM/CNPq, Brazil
| | - Katia C Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular - INCT-EM/CNPq, Brazil.
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Nunes DLM, Carvalho-Araujo MF, Silva-Cabral S, Rios T, Chagas-Lima AC, de Sousa G, Ramos I, Gomes SAO, Atella GC. Lipid metabolism dynamic in Triatomine Rhodnius prolixus during acute Trypanosoma rangeli infection. Acta Trop 2023; 248:107032. [PMID: 37838024 DOI: 10.1016/j.actatropica.2023.107032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 09/18/2023] [Accepted: 09/19/2023] [Indexed: 10/16/2023]
Abstract
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 qRT‒PCR 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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Affiliation(s)
- Daiene Lopes Moreira Nunes
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Maria Fernanda Carvalho-Araujo
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Suellen Silva-Cabral
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Thamara Rios
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Alessandra Catarina Chagas-Lima
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Géssica de Sousa
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Isabela Ramos
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Suzete A O Gomes
- Laboratório de Biologia de Insetos, Universidade Federal Fluminense, Niterói, RJ, Brazil
| | - Georgia C Atella
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
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Andrade LC, Majerowicz D, Oliveira PL, Guarneri AA. Alterations in energy metabolism of Rhodnius prolixus induced by Trypanosoma rangeli infection. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2023; 159:103987. [PMID: 37429385 DOI: 10.1016/j.ibmb.2023.103987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 07/07/2023] [Accepted: 07/07/2023] [Indexed: 07/12/2023]
Abstract
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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Affiliation(s)
- Laila C Andrade
- Vector Behavior and Pathogen Interaction Group, Instituto René Rachou, Fiocruz, Avenida Augusto de Lima, 1715, Belo Horizonte, MG, CEP 30190-009, Brazil
| | - David Majerowicz
- Departamento de Biotecnologia Farmacêutica, Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho, 373, Prédio do CCS, bloco A, 2° andar, sala 48, CEP: 21941-590, Cidade Universitária, Rio de Janeiro, Brazil; Programa de Pós-Graduação em Biociências, Universidade do Estado do Rio de Janeiro, Brazil; INCT-EM, Brazil
| | - Pedro L Oliveira
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Avenida Carlos Chagas Filho, 373, Ilha do Fundão, Rio de Janeiro, 21941-902, Brazil; INCT-EM, Brazil
| | - Alessandra A Guarneri
- Vector Behavior and Pathogen Interaction Group, Instituto René Rachou, Fiocruz, Avenida Augusto de Lima, 1715, Belo Horizonte, MG, CEP 30190-009, Brazil; INCT-EM, Brazil.
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De Paula IF, Santos-Araujo S, Majerowicz D, Ramos I, Gondim KC. Knockdown of carnitine palmitoyltransferase I (CPT1) reduces fat body lipid mobilization and resistance to starvation in the insect vector Rhodnius prolixus. Front Physiol 2023; 14:1201670. [PMID: 37469565 PMCID: PMC10352773 DOI: 10.3389/fphys.2023.1201670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Accepted: 06/21/2023] [Indexed: 07/21/2023] Open
Abstract
The energy stored in fatty acids is essential for several critical activities of insects, such as embryogenesis, oviposition, and flight. Rhodnius prolixus is an obligatory hematophagous hemipteran and vector of Chagas disease, and it feeds infrequently on very large blood meals. As digestion slowly occurs, lipids are synthesized and accumulate in the fat body, mainly as triacylglycerol, in lipid droplets. Between feeding bouts, proper mobilization and oxidation of stored lipids are crucial for survival, and released fatty acids are oxidized by mitochondrial β-oxidation. Carnitine palmitoyl transferase I (CPT1) is the enzyme that catalyzes the first reaction of the carnitine shuttle, where the activated fatty acid, acyl-CoA, is converted to acyl-carnitine to be transported into the mitochondria. Here, we investigated the role of CPT1 in lipid metabolism and in resistance to starvation in Rhodnius prolixus. The expression of the CPT1 gene (RhoprCpt1) was determined in the organs of adult females on the fourth day after a blood meal, and the flight muscle showed higher expression levels than the ovary, fat body, and anterior and posterior midgut. RhoprCpt1 expression in the fat body dramatically decreased after feeding, and started to increase again 10 days later, but no changes were observed in the flight muscle. β-oxidation rates were determined in flight muscle and fat body homogenates with the use of 3H-palmitate, and in unfed females, they were higher in the flight muscle. In the fat body, lipid oxidation activity did not show any variation before or at different days after feeding, and was not affected by the presence of etomoxir or malonyl-CoA. We used RNAi and generated RhoprCPT1-deficient insects, which surprisingly did not show a decrease in measured 3H-palmitate oxidation rates. However, the RNAi-knockdown females presented increased amounts of triacylglycerol and larger lipid droplets in the fat body, but not in the flight muscle. When subjected to starvation, these insects had a shorter lifespan. These results indicated that the inhibition of RhoprCpt1 expression compromised lipid mobilization and affected resistance to starvation.
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Affiliation(s)
- Iron F. De Paula
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Samara Santos-Araujo
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - David Majerowicz
- Departamento de Biotecnologia Farmacêutica, Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Programa de Pós-Graduação em Biociências, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Isabela Ramos
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Katia C. Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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Almeida-Oliveira F, Santos-Araujo S, Carvalho-Kelly LF, Macedo-Silva A, Meyer-Fernandes JR, Gondim KC, Majerowicz D. ATP synthase affects lipid metabolism in the kissing bug Rhodnius prolixus beyond its role in energy metabolism. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2023:103956. [PMID: 37196906 DOI: 10.1016/j.ibmb.2023.103956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 04/19/2023] [Accepted: 04/28/2023] [Indexed: 05/19/2023]
Abstract
ATP synthase plays an essential role in mitochondrial metabolism, being responsible for the production of ATP in oxidative phosphorylation. However, recent results have shown that it may also be present in the cell membrane, involved in lipophorin binding to its receptors. Here, we used a functional genetics approach to investigate the roles of ATP synthase in lipid metabolism in the kissing bug Rhodnius prolixus. The genome of R. prolixus encodes five nucleotide-binding domain genes of the ATP synthase alpha and beta family, including the alpha and beta subunits of ATP synthase (RpATPSynA and RpATPSynB), and the catalytic and non-catalytic subunits of the vacuolar ATPase (RpVha68 and RpVha55). These genes were expressed in all analyzed organs, being their expression highest in the ovaries, fat body and flight muscle. Feeding did not regulate the expression of ATP synthases in the posterior midgut or fat body. Furthermore, ATP synthase is present in the fat body's mitochondrial and membrane fractions. RpATPSynB knockdown by RNAi impaired ovarian development and reduced egg-laying by approximately 85%. Furthermore, the lack of RpATPSynB increased the amount of triacylglycerol in the fat body due to increased de novo fatty acid synthesis and reduced transfer of lipids to lipophorin. RpATPSynA knockdown had similar effects, with altered ovarian development, reduced oviposition, and triacylglycerol accumulation in the fat body. However, ATP synthases knockdown had only a slight effect on the amount of ATP in the fat body. These results support the hypothesis that ATP synthase has a direct role in lipid metabolism and lipophorin physiology, which are not directly due to changes in energy metabolism.
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Affiliation(s)
| | - Samara Santos-Araujo
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil
| | | | - Alessa Macedo-Silva
- Programa de Pós-Graduação em Biociências, Universidade do Estado do Rio de Janeiro, Brazil
| | | | - Katia C Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Brazil
| | - David Majerowicz
- Programa de Pós-Graduação em Biociências, Universidade do Estado do Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Brazil; Departamento de Biotecnologia Farmacêutica, Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Brazil.
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Braz V, Selim L, Gomes G, Costa ML, Mermelstein C, Gondim KC. Blood meal digestion and changes in lipid reserves are associated with the post-ecdysis development of the flight muscle and ovary in young adults of Rhodnius prolixus. JOURNAL OF INSECT PHYSIOLOGY 2023; 146:104492. [PMID: 36801397 DOI: 10.1016/j.jinsphys.2023.104492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 02/03/2023] [Accepted: 02/16/2023] [Indexed: 06/18/2023]
Abstract
Rhodnius prolixus is a hemimetabolous, hematophagous insect, and both nymphs and adults feed exclusively on blood. The blood feeding triggers the molting process and, after five nymphal instar stages, the insect reaches the winged adult form. After the final ecdysis, the young adult still has a lot of blood in the midgut and, thus, we have investigated the changes in protein and lipid contents that are observed in the insect organs as digestion continues after molting. Total midgut protein content decreased during the days after the ecdysis, and digestion was finished fifteen days later. Simultaneously, proteins and triacylglycerols present in the fat body were mobilized, and their contents decreased, whereas they increased in both the ovary and the flight muscle. In order to evaluate the activity of de novo lipogenesis of each organ, the fat body, ovary and flight muscle were incubated in the presence of radiolabeled acetate, and the fat body showed the highest efficiency rate (around 47%) to convert the taken up acetate into lipids. The levels of de novo lipid synthesis in the flight muscle and ovary were very low. When 3H-palmitate was injected into the young females, its incorporation by the flight muscle was higher than by the ovary or the fat body. In the flight muscle, the 3H-palmitate was similarly distributed amongst triacylglycerols, phospholipids, diacylglycerols and free fatty acids, while in the ovary and fat body it was mostly found in triacylglycerols and phospholipids. The flight muscle was not fully developed after the molt, and at day two no lipid droplets were observed. At day five, very small lipid droplets were present, and they increased in size up to day fifteen. The diameter of the muscle fibers also increased from day two to fifteen, as well as the internuclear distance, indicating that muscle hypertrophy occurred along these days. The lipid droplets from the fat body showed a different pattern, and their diameter decreased after day two, but started to increase again at day ten. The data presented herein describes the development of the flight muscle after the final ecdysis, and modifications that occur regarding lipid stores. We show that, after molting, substrates that are present in the midgut and fat body are mobilized and directed to the ovary and flight muscle, for the adults of R. prolixus to be ready to feed and reproduce.
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Affiliation(s)
- Valdir Braz
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Lukas Selim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Geyse Gomes
- Laboratório de Diferenciação Muscular, Instituto de Ciências Biomédicas, UFRJ Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Manoel Luis Costa
- Laboratório de Diferenciação Muscular, Instituto de Ciências Biomédicas, UFRJ Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Claudia Mermelstein
- Laboratório de Diferenciação Muscular, Instituto de Ciências Biomédicas, UFRJ Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Katia C Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
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Moraes B, Braz V, Santos-Araujo S, Oliveira IA, Bomfim L, Ramos I, Gondim KC. Deficiency of Acetyl-CoA Carboxylase Impairs Digestion, Lipid Synthesis, and Reproduction in the Kissing Bug Rhodnius prolixus. Front Physiol 2022; 13:934667. [PMID: 35936892 PMCID: PMC9353303 DOI: 10.3389/fphys.2022.934667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 06/14/2022] [Indexed: 11/14/2022] Open
Abstract
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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Affiliation(s)
- Bruno Moraes
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Valdir Braz
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Samara Santos-Araujo
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Isadora A. Oliveira
- Centro de Espectrometria de Massas de Biomoléculas, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Larissa Bomfim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Isabela Ramos
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Katia C. Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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10
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Arêdes DS, De Paula IF, Santos-Araujo S, Gondim KC. Silencing of Mitochondrial Trifunctional Protein A Subunit (HADHA) Increases Lipid Stores, and Reduces Oviposition and Flight Capacity in the Vector Insect Rhodnius prolixus. FRONTIERS IN INSECT SCIENCE 2022; 2:885172. [PMID: 38468769 PMCID: PMC10926480 DOI: 10.3389/finsc.2022.885172] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 05/16/2022] [Indexed: 03/13/2024]
Abstract
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 β-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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Affiliation(s)
| | | | | | - Katia C. Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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11
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Dynamics of maternal gene expression in Rhodnius prolixus. Sci Rep 2022; 12:6538. [PMID: 35449214 PMCID: PMC9023505 DOI: 10.1038/s41598-022-09874-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 03/14/2022] [Indexed: 11/08/2022] Open
Abstract
The study of developmental processes in Rhodnius prolixus has recently advanced with the sequencing of the genome. In this work, we analyze the maternal gene expression driving oogenesis and early embryogenesis in R. prolixus. We examined the transcriptional profile of mRNAs to establish the genes expressed across the ovary, unfertilized eggs and different embryonic stages of R. prolixus until the formation of the germ band anlage (0, 12, 24, and 48 h post egg laying). We identified 81 putative maternal and ovary-related genes and validated their expression by qRT-PCR. We validate the function of the ortholog gene Bicaudal-D (Rp-BicD) by in situ hybridization and parental RNAi. Consistent with a role in oogenesis and early development of R. prolixus, we show that lack of Rp-BicD does not significantly affect oogenesis but impairs the formation of the blastoderm. Based on our findings, we propose three times of action for maternal genes during oogenesis and embryogenesis in R. prolixus.
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12
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Kaczmarek A, Boguś M. The metabolism and role of free fatty acids in key physiological processes in insects of medical, veterinary and forensic importance. PeerJ 2021; 9:e12563. [PMID: 35036124 PMCID: PMC8710053 DOI: 10.7717/peerj.12563] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Accepted: 11/07/2021] [Indexed: 12/16/2022] Open
Abstract
Insects are the most widespread group of organisms and more than one million species have been described. These animals have significant ecological functions, for example they are pollinators of many types of plants. However, they also have direct influence on human life in different manners. They have high medical and veterinary significance, stemming from their role as vectors of disease and infection of wounds and necrotic tissue; they are also plant pests, parasitoids and predators whose activities can influence agriculture. In addition, their use in medical treatments, such as maggot therapy of gangrene and wounds, has grown considerably. They also have many uses in forensic science to determine the minimum post-mortem interval and provide valuable information about the movement of the body, cause of the death, drug use, or poisoning. It has also been proposed that they may be used as model organisms to replace mammal systems in research. The present review describes the role of free fatty acids (FFAs) in key physiological processes in insects. By focusing on insects of medical, veterinary significance, we have limited our description of the physiological processes to those most important from the point of view of insect control; the study examines their effects on insect reproduction and resistance to the adverse effects of abiotic (low temperature) and biotic (pathogens) factors.
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Affiliation(s)
- Agata Kaczmarek
- Witold Stefański Institute of Parasitology, Polish Academy of Sciences, Warsaw, Poland
| | - Mieczysława Boguś
- Witold Stefański Institute of Parasitology, Polish Academy of Sciences, Warsaw, Poland
- Biomibo, Warsaw, Poland
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13
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Nascimento PVP, Almeida-Oliveira F, Macedo-Silva A, Ausina P, Motinha C, Sola-Penna M, Majerowicz D. Gene annotation of nuclear receptor superfamily genes in the kissing bug Rhodnius prolixus and the effects of 20-hydroxyecdysone on lipid metabolism. INSECT MOLECULAR BIOLOGY 2021; 30:297-314. [PMID: 33455040 DOI: 10.1111/imb.12696] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 11/29/2020] [Accepted: 01/11/2021] [Indexed: 06/12/2023]
Abstract
The hormone 20-hydroxyecdysone is fundamental for regulating moulting and metamorphosis in immature insects, and it plays a role in physiological regulation in adult insects. This hormone acts by binding and activating a receptor, the ecdysone receptor, which is part of the nuclear receptor gene superfamily. Here, we analyse the genome of the kissing bug Rhodnius prolixus to annotate the nuclear receptor superfamily genes. The R. prolixus genome displays a possible duplication of the HNF4 gene. All the analysed insect organs express most nuclear receptor genes as shown by RT-PCR. The quantitative PCR analysis showed that the RpEcR and RpUSP genes are highly expressed in the testis, while the RpHNF4-1 and RpHNF4-2 genes are more active in the fat body and ovaries and in the anterior midgut, respectively. Feeding does not induce detectable changes in the expression of these genes in the fat body. However, the expression of the RpHNF4-2 gene is always higher than that of RpHNF4-1. Treating adult females with 20-hydroxyecdysone increased the amount of triacylglycerol stored in the fat bodies by increasing their lipogenic capacity. These results indicate that 20-hydroxyecdysone acts on the lipid metabolism of adult insects, although the underlying mechanism is not clear.
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Affiliation(s)
- P V P Nascimento
- Departamento de Biotecnologia Farmacêutica, Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - F Almeida-Oliveira
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - A Macedo-Silva
- Departamento de Biotecnologia Farmacêutica, Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - P Ausina
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - C Motinha
- Departamento de Biotecnologia Farmacêutica, Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - M Sola-Penna
- Departamento de Biotecnologia Farmacêutica, Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - D Majerowicz
- Departamento de Biotecnologia Farmacêutica, Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Rio de Janeiro, Brazil
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14
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Saraiva FB, Alves-Bezerra M, Majerowicz D, Paes-Vieira L, Braz V, Almeida MGMD, Meyer-Fernandes JR, Gondim KC. Blood meal drives de novo lipogenesis in the fat body of Rhodnius prolixus. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2021; 133:103511. [PMID: 33278628 DOI: 10.1016/j.ibmb.2020.103511] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 11/18/2020] [Accepted: 11/24/2020] [Indexed: 06/12/2023]
Abstract
In insects, lipids are stored in the fat body mainly as triacylglycerol. Lipids can be directly provided by digestion and incorporated from the hemolymph, or synthesized de novo from other substrates such as carbohydrates and amino acids. The first step in de novo lipid synthesis is catalyzed by acetyl-CoA carboxylase (ACC), which carboxylates acetyl-CoA to form malonyl-CoA. Rhodnius prolixus is a hematophagous insect vector of Chagas disease and feeds exclusively on large and infrequent blood meals. Adult females slowly digest the blood and concomitantly accumulate lipids in the fat body. In this study, we investigated the regulation of R. prolixus ACC (RhoprACC) expression and de novo lipogenesis activity in adult females at different nutritional and metabolic conditions. A phylogenetic analysis showed that insects, similar to other arthropods and unlike vertebrate animals, have only one ACC gene. In females on the fourth day after a blood meal, RhoprACC transcript levels were similar in the anterior and posterior midgut, fat body and ovary and higher in the flight muscles. In the fat body, gene expression was higher in fasted females and decreased after a blood meal. In the posterior midgut it increased after feeding, and no variation was observed in the flight muscle. RhoprACC protein content analysis of the fat body revealed a profile similar to the gene expression, with higher protein contents before feeding and in the first two days after a blood meal. Radiolabeled acetate was used to follow de novo lipid synthesis in the fat body and it was incorporated mainly into triacylglycerol, diacylglycerol and phospholipids. This lipogenic activity was inhibited by soraphen A, an ACC inhibitor, and it varied according to the insect metabolic status. De novo lipogenesis was very low in starved females and increased during the initial days after a blood meal. The flight muscles had a very low capacity to synthesize lipids when compared to the fat body. Radiolabeled leucine was also used as a substrate for de novo lipogenesis and the same lipid classes were formed. In conclusion, our results indicate that the blood meal induces the utilization of diet-derived amino acids by de novo lipogenesis in the fat body, and that the control of this activity does not occur at the RhoprACC gene or protein expression level.
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Affiliation(s)
- Felipe B Saraiva
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil
| | - Michele Alves-Bezerra
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - David Majerowicz
- Departamento de Biotecnologia Farmacêutica, Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Brazil
| | - Lisvane Paes-Vieira
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil
| | - Valdir Braz
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil
| | - Muriel G M D Almeida
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil
| | | | - Katia C Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil.
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15
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Entringer PF, Majerowicz D, Gondim KC. The Fate of Dietary Cholesterol in the Kissing Bug Rhodnius prolixus. Front Physiol 2021; 12:654565. [PMID: 33868022 PMCID: PMC8047208 DOI: 10.3389/fphys.2021.654565] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Accepted: 02/23/2021] [Indexed: 11/13/2022] Open
Abstract
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.
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Affiliation(s)
- Petter F. Entringer
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - David Majerowicz
- Departamento de Biotecnologia Farmacêutica, Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Katia C. Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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16
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Silva ERMN, Santos LV, Caiado MS, Hastenreiter LSN, Fonseca SRR, Carbajal-de-la-Fuente AL, Carvalho MG, Pontes EG. The influence of larval density on triacylglycerol content in Aedes aegypti (Linnaeus) (Diptera: Culicidae). ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2021; 106:e21757. [PMID: 33145814 DOI: 10.1002/arch.21757] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 09/09/2020] [Accepted: 10/09/2020] [Indexed: 06/11/2023]
Abstract
Given the importance of Aedes aegypti as an arbovirus vector, understanding the impact of population density during larval development is fundamental to improve control methods. The aims of this study were to analyze the effects of larval density on the triacylglycerol (TAG) reserves, fecundity, and the size of mosquitos. To evaluate the influence of density on the amount of TAG in the different stages of development of A. aegypti, the larvae were reared in densities of 0.04, 0.32, and 0.8 larvae/ml, represented by D1, D2, and D3, respectively. Larval rearing density affected the amount of TAG in the different developmental stages of this insect. The group reared with the highest population density (D3) presented greater storage of TAG, except when analyzing the amount of TAG μg/protein in the fat body of blood-fed females. In addition, it was possible to observe higher resistance to fasting and a greater number of eggs laid. Insects reared in D2 and D3 were larger than those in the D1 group. This study provides interesting data for future investigations on how the density of larval rearing affects the lipid metabolism for synthesis and mobilization of TAG stored in A. aegypti and how it influences size and reproduction.
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Affiliation(s)
- Elaine R M N Silva
- Departamento de Bioquímica, Instituto de Química, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil
| | - Luan V Santos
- Departamento de Bioquímica, Instituto de Química, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil
| | - Matheus S Caiado
- Departamento de Bioquímica, Instituto de Química, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil
| | - Luana S N Hastenreiter
- Departamento de Bioquímica, Instituto de Química, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil
| | - Sabrina R R Fonseca
- Departamento de Química Orgânica, Instituto de Química, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil
| | - Ana L Carbajal-de-la-Fuente
- Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
- Centro Nacional de Diagnóstico e Investigación en Endemo-Epidemias (CeNDIE), Administración Nacional de Laboratorios e Institutos de Salud "Dr. Carlos Malbrán" (ANLIS), Buenos Aires, Argentina
| | - Mario G Carvalho
- Departamento de Química Orgânica, Instituto de Química, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil
| | - Emerson G Pontes
- Departamento de Bioquímica, Instituto de Química, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil
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17
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Santos-Araujo S, Bomfim L, Araripe LO, Bruno R, Ramos I, Gondim KC. Silencing of ATG6 and ATG8 promotes increased levels of triacylglycerol (TAG) in the fat body during prolonged starvation periods in the Chagas disease vector Rhodnius prolixus. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2020; 127:103484. [PMID: 33022370 DOI: 10.1016/j.ibmb.2020.103484] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 09/18/2020] [Accepted: 09/29/2020] [Indexed: 06/11/2023]
Abstract
Rhodnius prolixus is an obligatorily hematophagous insect known as an important vector of Chagas disease. Autophagy is a conserved cellular mechanism that acts in response to nutrient starvation, where components of the cytoplasm are sequestered by a double membrane organelle, named autophagosome, which is targeted to fuse with the lysosome for degradation. Lipophagy is the process of lipid degradation by selective autophagy, where autophagosomes sequester lipid droplets and degrade triacylglycerol (TAG) generating free fatty acids for β-oxidation. Here, two essential genes of the autophagic pathway, Atg6/Beclin1 (RpAtg6) and Atg8/LC3 (RpAtg8), were silenced and the storage of lipids during starvation in Rhodnius prolixus was monitored. We found that RNAi knockdown of both RpAtg6 and RpAtg8 resulted in higher levels of TAG in the fat body and the flight muscle, 24 days after the blood meal, as well as a larger average diameter of the lipid droplets in the fat body, as seen by Nile Red staining under the confocal fluorescence microscope. Silenced starved insects had lower survival rates when compared to control insects. Accordingly, when examined during the starvation period for monitored activity, silenced insects had lower spontaneous locomotor activity and lower forced flight rates. Furthermore, we found that some genes involved in lipid metabolism had their expression levels altered in silenced insects, such as the Brummer lipase (down regulated) and the adipokinetic hormone receptor (up regulated), suggesting that, as previously observed in mammalian models, the autophagy and neutral lipolysis machineries are interconnected at the transcriptional level. Altogether, our data indicate that autophagy in the fat body is important to allow insects to mobilize energy from lipid stores.
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Affiliation(s)
- Samara Santos-Araujo
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil
| | - Larissa Bomfim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil
| | - Luciana O Araripe
- Laboratório de Biologia Molecular de Insetos, Instituto Oswaldo Cruz. Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular - INCT-EM/CNPq, Brazil
| | - Rafaela Bruno
- Laboratório de Biologia Molecular de Insetos, Instituto Oswaldo Cruz. Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular - INCT-EM/CNPq, Brazil
| | - Isabela Ramos
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular - INCT-EM/CNPq, Brazil
| | - Katia C Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular - INCT-EM/CNPq, Brazil.
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18
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Abstract
Abstract
The aim of this review is to discuss the usage of insect fats as an energy source in animal nutrition. Insects are a rich carrier of proteins, fat, and minerals. They are successfully introduced in animal diets (poultry, swine, rabbits, fish, and pets) as a source of many nutrients, including energy and essential fatty acids (FAs). The insects’ fat content and quality are highly affected by the type of substrate provided to the insects during the rearing period. The majority of the studies have shown that insect fats may be used as promising substitutes for conventional energy resources in animal nutrition without adverse effects on growth performance and feed utilization. They can positively affect meat quality by increasing the level of long-chain polyunsaturated FAs but may also positively influence animals by regulating the gut microbiota and stimulating the immune system. In conclusion, insect fat supplementation showed promising results in terms of their application in animal nutrition. However, compared to insect protein application, very few studies have been performed on insect fats. Therefore, because of the fat quality and content of insects, there is a need to extend experimentation regarding their implementation in animals’ diets as a replacement for conventional dietary energy resources.
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19
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Silva-Oliveira G, De Paula IF, Medina JM, Alves-Bezerra M, Gondim KC. Insulin receptor deficiency reduces lipid synthesis and reproductive function in the insect Rhodnius prolixus. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1866:158851. [PMID: 33160077 DOI: 10.1016/j.bbalip.2020.158851] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 10/20/2020] [Accepted: 10/22/2020] [Indexed: 12/26/2022]
Abstract
Rhodnius prolixus, a vector of Chagas disease, is a hematophagous insect that feeds exclusively on blood. Each blood meal is digested within the first fourteen days after feeding, providing substrates for lipid synthesis for storage and egg production. These events are precisely regulated and emerging evidence points to a key function of insulin-like peptides (ILPs) in this control. Here we investigated the role of insulin receptor in the regulation of nutrient metabolism in fed adult females. The expression of insulin receptor (RhoprIR) gene was determined in adult organs, and it was highest in ovaries and previtellogenic follicles. We generated insects with RNAi-mediated knockdown of RhoprIR to address the physiological role of this receptor. RhoprIR deficiency improved longevity and reduced triacylglycerol storage in the fat body, whereas blood digestion remained unchanged for seven days after blood meal. The lower lipid content was attributable to decreased de novo lipogenesis as well as reduced incorporation of hemolymph-derived fatty acids into newly synthesized lipids within this organ. Consistent with that, fat bodies from RhoprIR-deficient insects exhibited decreased gene expression levels of lipophorin receptor (RhoprLpR), glycerol-3-phosphate acyltransferase 1 and 4 (RhoprGpat1 and RhoprGpat4), and carnitine palmitoyltransferase 1 (RhoprCpt1). Although hemolymph lipid profile was not affected by RhoprIR disruption, the concentration of circulating vitellogenin was increased. In line with these changes, RhoprIR-deficient females exhibited smaller ovaries and a marked reduction in oviposition. Taken together, these findings support a key role of insulin receptor in nutrient homeostasis, lipid synthesis and egg production following a blood meal.
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Affiliation(s)
- Gleidson Silva-Oliveira
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil
| | - Iron F De Paula
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil
| | - Jorge M Medina
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil
| | - Michele Alves-Bezerra
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Houston, TX 77030, USA.
| | - Katia C Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Brazil.
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20
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Leyria J, Orchard I, Lange AB. What happens after a blood meal? A transcriptome analysis of the main tissues involved in egg production in Rhodnius prolixus, an insect vector of Chagas disease. PLoS Negl Trop Dis 2020; 14:e0008516. [PMID: 33057354 PMCID: PMC7591069 DOI: 10.1371/journal.pntd.0008516] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 10/27/2020] [Accepted: 09/23/2020] [Indexed: 12/17/2022] Open
Abstract
The blood-sucking hemipteran Rhodnius prolixus is a vector of Chagas disease, one of the most neglected tropical diseases affecting several million people, mostly in Latin America. The blood meal is an event with a high epidemiological impact since adult mated females feed several times, with each meal resulting in a bout of egg laying, and thereby the production of hundreds of offspring. By means of RNA-Sequencing (RNA-Seq) we have examined how a blood meal influences mRNA expression in the central nervous system (CNS), fat body and ovaries in order to promote egg production, focusing on tissue-specific responses under controlled nutritional conditions. We illustrate the cross talk between reproduction and a) lipids, proteins and trehalose metabolism, b) neuropeptide and neurohormonal signaling, and c) the immune system. Overall, our molecular evaluation confirms and supports previous studies and provides an invaluable molecular resource for future investigations on different tissues involved in successful reproductive events. These analyses serve as a starting point for new investigations, increasing the chances of developing novel strategies for vector population control by translational research, with less impact on the environment and more specificity for a particular organism.
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Affiliation(s)
- Jimena Leyria
- Department of Biology, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Ian Orchard
- Department of Biology, University of Toronto Mississauga, Mississauga, ON, Canada
| | - Angela B. Lange
- Department of Biology, University of Toronto Mississauga, Mississauga, ON, Canada
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21
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Almeida MGMD, Arêdes DS, Majerowicz D, Færgeman NJ, Knudsen J, Gondim KC. Expression of acyl-CoA-binding protein 5 from Rhodnius prolixus and its inhibition by RNA interference. PLoS One 2020; 15:e0227685. [PMID: 31935250 PMCID: PMC6959561 DOI: 10.1371/journal.pone.0227685] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 12/24/2019] [Indexed: 12/03/2022] Open
Abstract
The acyl-CoA-binding proteins (ACBP) act by regulating the availability of acyl-CoA in the cytoplasm and must have essential functions in lipid metabolism. The genome of the kissing-bug Rhodnius prolixus encodes five proteins of this family, but little is known about them. In this study we investigated the expression and function of RpACBP-5. Feeding induced RpACBP-5 gene expression in the posterior midgut, and an increase of about four times was observed two days after the blood meal. However, the amount of protein, which was only detected in this organ, did not change during digestion. The RpACBP-5 gene was also highly expressed in pre-vitellogenic and vitellogenic oocytes. Recombinant RpACBP-5 was shown to bind to acyl-CoA of different lengths, and it exhibited nanomolar affinity to lauroyl-CoA in an isothermal titration assay, indicating that RpACBP-5 is a functional ACBP. RpACBP-5 knockdown by RNA interference did not affect digestion, egg laying and hatching, survival, or accumulation of triacylglycerol in the fat body and oocytes. Similarly, double knockdown of RpACBP-1 and RpACBP-5 did not alter egg laying and hatching, survival, accumulation of triacylglycerol in the fat body and oocytes, or the neutral lipid composition of the posterior midgut or hemolymph. These results show that RpACBP-5 is a functional ACBP but indicate that the lack of a detectable phenotype in the knockdown insects may be a consequence of functional overlap of the proteins of the ACBP family found in the insect.
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Affiliation(s)
- Muriel G. M. D. Almeida
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Daniela S. Arêdes
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - David Majerowicz
- Institut for Biokemi og Molekylær Biologi, Syddansk Universitet, Odense, Denmark
- Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Nils J. Færgeman
- Institut for Biokemi og Molekylær Biologi, Syddansk Universitet, Odense, Denmark
| | - Jens Knudsen
- Institut for Biokemi og Molekylær Biologi, Syddansk Universitet, Odense, Denmark
| | - Katia C. Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- * E-mail:
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Fruttero LL, Leyria J, Moyetta NR, Ramos FO, Settembrini BP, Canavoso LE. The Fat Body of the Hematophagous Insect, Panstrongylus megistus (Hemiptera: Reduviidae): Histological Features and Participation of the β-Chain of ATP Synthase in the Lipophorin-Mediated Lipid Transfer. JOURNAL OF INSECT SCIENCE (ONLINE) 2019; 19:5539020. [PMID: 31346627 PMCID: PMC6658809 DOI: 10.1093/jisesa/iez078] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Indexed: 05/09/2023]
Abstract
In insects, lipid transfer to the tissues is mediated by lipophorin, the major circulating lipoprotein, mainly through a nonendocytic pathway involving docking receptors. Currently, the role of such receptors in lipid metabolism remains poorly understood. In this work, we performed a histological characterization of the fat body of the Chagas' disease vector, Panstrongylus megistus (Burmeister), subjected to different nutritional conditions. In addition, we addressed the role of the β-chain of ATP synthase (β-ATPase) in the process of lipid transfer from lipophorin to the fat body. Fifth-instar nymphs in either fasting or fed condition were employed in the assays. Histological examination revealed that the fat body was composed by diverse trophocyte phenotypes. In the fasting condition, the cells were smaller and presented a homogeneous cytoplasmic content. The fat body of fed insects increased in size mainly due to the enlargement of lipid stores. In this condition, trophocytes contained abundant lipid droplets, and the rough endoplasmic reticulum was highly developed and mitochondria appeared elongated. Immunofluorescence assays showed that the β-ATPase, a putative lipophorin receptor, was located on the surface of fat body cells colocalizing partially with lipophorin, which suggests their interaction. No changes in β-ATPase expression were found in fasting and fed insects. Blocking the lipophorin-β-ATPase interaction impaired the lipophorin-mediated lipid transfer to the fat body. The results showed that the nutritional status of the insect influenced the morphohistological features of the tissue. Besides, these findings suggest that β-ATPase functions as a lipophorin docking receptor in the fat body.
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Affiliation(s)
- Leonardo L Fruttero
- Departamento de Bioquímica Clínica, Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba CP, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
| | - Jimena Leyria
- Departamento de Bioquímica Clínica, Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba CP, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
| | - Natalia R Moyetta
- Departamento de Bioquímica Clínica, Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba CP, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
| | - Fabian O Ramos
- Departamento de Bioquímica Clínica, Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba CP, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
| | - Beatriz P Settembrini
- Museo Argentino de Ciencias Naturales Bernardino Rivadavia (CONICET), Buenos Aires, Argentina
| | - Lilián E Canavoso
- Departamento de Bioquímica Clínica, Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba CP, Argentina
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba, Argentina
- Corresponding author, e-mail:
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Gondim KC, Atella GC, Pontes EG, Majerowicz D. Lipid metabolism in insect disease vectors. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2018; 101:108-123. [PMID: 30171905 DOI: 10.1016/j.ibmb.2018.08.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Revised: 08/17/2018] [Accepted: 08/26/2018] [Indexed: 06/08/2023]
Abstract
More than a third of the world population is at constant risk of contracting some insect-transmitted disease, such as Dengue fever, Zika virus disease, malaria, Chagas' disease, African trypanosomiasis, and others. Independent of the life cycle of the pathogen causing the disease, the insect vector hematophagous habit is a common and crucial trait for the transmission of all these diseases. This lifestyle is unique, as hematophagous insects feed on blood, a diet that is rich in protein but relatively poor in lipids and carbohydrates, in huge amounts and low frequency. Another unique feature of these insects is that blood meal triggers essential metabolic processes, as molting and oogenesis and, in this way, regulates the expression of various genes that are involved in these events. In this paper, we review current knowledge of the physiology and biochemistry of lipid metabolism in insect disease vectors, comparing with classical models whenever possible. We address lipid digestion and absorption, hemolymphatic transport, and lipid storage by the fat body and ovary. In this context, both de novo fatty acid and triacylglycerol synthesis are discussed, including the related fatty acid activation process and the intracellular lipid binding proteins. As lipids are stored in order to be mobilized later on, e.g. for flight activity or survivorship, lipolysis and β-oxidation are also considered. All these events need to be finely regulated, and the role of hormones in this control is summarized. Finally, we also review information about infection, when vector insect physiology is affected, and there is a crosstalk between its immune system and lipid metabolism. There is not abundant information about lipid metabolism in vector insects, and significant current gaps in the field are indicated, as well as questions to be answered in the future.
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Affiliation(s)
- Katia C Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
| | - Georgia C Atella
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Emerson G Pontes
- Departamento de Bioquímica, Instituto de Química, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ, Brazil
| | - David Majerowicz
- Departamento de Biotecnologia Farmacêutica, Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
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Alves-Bezerra M, Ramos IB, De Paula IF, Maya-Monteiro CM, Klett EL, Coleman RA, Gondim KC. Deficiency of glycerol-3-phosphate acyltransferase 1 decreases triacylglycerol storage and induces fatty acid oxidation in insect fat body. Biochim Biophys Acta Mol Cell Biol Lipids 2017; 1862:324-336. [DOI: 10.1016/j.bbalip.2016.12.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Revised: 12/06/2016] [Accepted: 12/08/2016] [Indexed: 12/19/2022]
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Lavarías S, Ocon C, van Oosterom VL, Laino A, Medesani DA, Fassiano A, Garda H, Donadelli J, de Molina MR, Capítulo AR. Multibiomarker responses in aquatic insect Belostoma elegans (Hemiptera) to organic pollution in freshwater system. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:1322-1337. [PMID: 27771882 DOI: 10.1007/s11356-016-7493-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 08/18/2016] [Indexed: 06/06/2023]
Abstract
The present study analyzes a battery of biomarkers in the water bug Belostoma elegans from a stream polluted with organic matter (OMS), and another one considered as reference site (RS) during spring-summer season (December to March). Biochemical parameters of glucidic, lipidic and oxidative metabolic pathways were analyzed in males and females of this insect. In general, no significant differences were observed in all biomarkers assayed between both sexes, except lactate concentration which was higher in males than in females (p < 0.0006) in the first three months. About carbohydrate metabolism parameters, only pyruvate-kinase showed significant differences between insects collected in both streams (p < 0.05) during December. However, the total lipid content, saturated fatty acid, and mainly triacylglycerol were higher in insects from RS compared to those from OMS (p < 0.002) in all sampled months. Levels of lipoperoxidation, protein oxidation, reduced glutathione and glutathione-S-transferase activity showed no differences between insects collected from both streams. Nevertheless, the significant increase observed in superoxide dismutase and catalase activities (p < 0.004) could be due to the elevated oxidative metabolism in insects from RS compared to those from OMS with lower dissolved oxygen. Regarding those responding parameters, males accounted for the differences between the two sites during the study period. In conclusion, our results support that lipidic energetic reserves and antioxidant enzyme activities in B. elegans could be used as biomarkers of environmental pollution by organic matter.
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Affiliation(s)
- S Lavarías
- Instituto de Limnología de La Plata (ILPLA) CONICET CCT La Plata-Universidad Nacional de La Plata (UNLP), Boulevard 120 y 62, 1900, La Plata, Argentina.
| | - C Ocon
- Instituto de Limnología de La Plata (ILPLA) CONICET CCT La Plata-Universidad Nacional de La Plata (UNLP), Boulevard 120 y 62, 1900, La Plata, Argentina
| | - V López van Oosterom
- Instituto de Limnología de La Plata (ILPLA) CONICET CCT La Plata-Universidad Nacional de La Plata (UNLP), Boulevard 120 y 62, 1900, La Plata, Argentina
| | - A Laino
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP) CONICET CCT La Plata-Universidad Nacional de La Plata (UNLP), La Plata, Argentina
| | - D A Medesani
- IQUIBICEN Fac. Cs. Exactas y Naturales. Universidad de Buenos Aires (UBA), Buenos Aires, Argentina
| | - A Fassiano
- IQUIBICEN Fac. Cs. Exactas y Naturales. Universidad de Buenos Aires (UBA), Buenos Aires, Argentina
| | - H Garda
- Instituto de Investigaciones Bioquímicas de La Plata (INIBIOLP) CONICET CCT La Plata-Universidad Nacional de La Plata (UNLP), La Plata, Argentina
| | - J Donadelli
- Instituto de Limnología de La Plata (ILPLA) CONICET CCT La Plata-Universidad Nacional de La Plata (UNLP), Boulevard 120 y 62, 1900, La Plata, Argentina
| | - M Ríos de Molina
- IQUIBICEN Fac. Cs. Exactas y Naturales. Universidad de Buenos Aires (UBA), Buenos Aires, Argentina
| | - A Rodrigues Capítulo
- Instituto de Limnología de La Plata (ILPLA) CONICET CCT La Plata-Universidad Nacional de La Plata (UNLP), Boulevard 120 y 62, 1900, La Plata, Argentina
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26
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Lipid metabolism in Rhodnius prolixus: Lessons from the genome. Gene 2016; 596:27-44. [PMID: 27697616 DOI: 10.1016/j.gene.2016.09.045] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2016] [Revised: 09/22/2016] [Accepted: 09/28/2016] [Indexed: 01/01/2023]
Abstract
The kissing bug Rhodnius prolixus is both an important vector of Chagas' disease and an interesting model for investigation into the field of physiology, including lipid metabolism. The publication of this insect genome will bring a huge amount of new molecular biology data to be used in future experiments. Although this work represents a promising scenario, a preliminary analysis of the sequence data is necessary to identify and annotate the genes involved in lipid metabolism. Here, we used bioinformatics tools and gene expression analysis to explore genes from different genes families and pathways, including genes for fat breakdown, as lipases and phospholipases, and enzymes from β-oxidation, fatty acid metabolism, and acyl-CoA and glycerolipid synthesis. The R. prolixus genome encodes 31 putative lipase genes, including 21 neutral lipases and 5 acid lipases. The expression profiles of some of these genes were analyzed. We were able to identify nine phospholipase A2 genes. A variety of gene families that participate in fatty acid synthesis and modification were studied, including fatty acid synthase, elongase, desaturase and reductase. Concerning the synthesis of glycerolipids, we found a second isoform of glycerol-3-phosphate acyltransferase that was ubiquitously expressed throughout the organs. Finally, all genes involved in fatty acid β-oxidation were identified, but not a long-chain acyl-CoA dehydrogenase. These results provide fundamental data to be used in future research on insect lipid metabolism and its possible relevance to Chagas' disease transmission.
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Majerowicz D, Hannibal-Bach HK, Castro RSC, Bozaquel-Morais BL, Alves-Bezerra M, Grillo LAM, Masuda CA, Færgeman NJ, Knudsen J, Gondim KC. The ACBP gene family in Rhodnius prolixus: Expression, characterization and function of RpACBP-1. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2016; 72:41-52. [PMID: 27001070 DOI: 10.1016/j.ibmb.2016.03.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 03/04/2016] [Accepted: 03/16/2016] [Indexed: 06/05/2023]
Abstract
The acyl-CoA-binding proteins (ACBP) constitute a family of conserved proteins that bind acyl-CoA with high affinity and protect it from hydrolysis. Thus, ACBPs may have essential roles in basal cellular lipid metabolism. The genome of the insect Rhodnius prolixus encodes five ACBP genes similar to those described for other insect species. The qPCR analysis revealed that these genes have characteristic expression profiles in insect organs, suggesting that they have specific roles in insect physiology. Recombinant RpACBP-1 was able to bind acyl-CoA in an in vitro gel-shift assay. Moreover, heterologous RpACBP-1 expression in acb1Δ mutant yeast rescued the multi-lobed vacuole phenotype, indicating that RpACBP-1 acts as a bona fide acyl-CoA-binding protein. RpACBP-1 knockdown using RNAi caused triacylglycerol accumulation in the insect posterior midgut and a reduction in the number of deposited eggs. The amount of stored triacylglycerol was reduced in flight muscle, and the incorporation of fatty acids in cholesteryl esters was increased in the fat body. These results showed that RpACBP-1 participates in several lipid metabolism steps in R. prolixus.
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Affiliation(s)
- David Majerowicz
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Institut for Biokemi og Molekylær Biologi, Syddansk Universitet, Odense, Denmark
| | - Hans K Hannibal-Bach
- Institut for Biokemi og Molekylær Biologi, Syddansk Universitet, Odense, Denmark
| | - Rodolfo S C Castro
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Bruno L Bozaquel-Morais
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Michele Alves-Bezerra
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Luciano A M Grillo
- Escola de Enfermagem e Farmácia, Universidade Federal de Alagoas, Maceió, Brazil
| | - Claudio A Masuda
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Nils J Færgeman
- Institut for Biokemi og Molekylær Biologi, Syddansk Universitet, Odense, Denmark
| | - Jens Knudsen
- Institut for Biokemi og Molekylær Biologi, Syddansk Universitet, Odense, Denmark
| | - Katia C Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular, Brazil.
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Alves-Bezerra M, Klett EL, De Paula IF, Ramos IB, Coleman RA, Gondim KC. Long-chain acyl-CoA synthetase 2 knockdown leads to decreased fatty acid oxidation in fat body and reduced reproductive capacity in the insect Rhodnius prolixus. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:650-62. [PMID: 27091636 DOI: 10.1016/j.bbalip.2016.04.007] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Revised: 03/16/2016] [Accepted: 04/13/2016] [Indexed: 10/21/2022]
Abstract
Long-chain acyl-CoA esters are important intermediates in lipid metabolism and are synthesized from fatty acids by long-chain acyl-CoA synthetases (ACSL). The hematophagous insect Rhodnius prolixus, a vector of Chagas' disease, produces glycerolipids in the midgut after a blood meal, which are stored as triacylglycerol in the fat body and eggs. We identified twenty acyl-CoA synthetase genes in R. prolixus, two encoding ACSL isoforms (RhoprAcsl1 and RhoprAcsl2). RhoprAcsl1 transcripts increased in posterior midgut on the second day after feeding, and RhoprAcsl2 was highly transcribed on the tenth day. Both enzymes were expressed in Escherichia coli. Recombinant RhoprACSL1 and RhoprACSL2 had broad pH optima (7.5-9.5 and 6.5-9.5, respectively), were inhibited by triacsin C, and were rosiglitazone-insensitive. Both showed similar apparent Km for palmitic and oleic acid (2-6 μM), but different Km for arachidonic acid (0.5 and 6 μM for RhoprACSL1-Flag and RhoprACSL2-Flag, respectively). The knockdown of RhoprAcsl1 did not result in noticeable phenotypes. However, RhoprACSL2 deficient insects exhibited a 2.5-fold increase in triacylglycerol content in the fat body, and 90% decrease in fatty acid β-oxidation. RhoprAcsl2 knockdown also resulted in 20% increase in lifespan, delayed digestion, 30% reduced oviposition, and 50% reduction in egg hatching. Laid eggs and hatched nymphs showed remarkable alterations in morphology. In summary, R. prolixus ACSL isoforms have distinct roles on lipid metabolism. Although RhoprACSL1 functions remain unclear, we propose that RhoprACSL2 is the main contributor for the formation of the intracellular acyl-CoA pool channeled for β-oxidation in the fat body, and is also required for normal reproduction.
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Affiliation(s)
- Michele Alves-Bezerra
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil; Department of Nutrition, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Eric L Klett
- Department of Nutrition, University of North Carolina, Chapel Hill, NC 27599, USA; Department of Medicine, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Iron F De Paula
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Isabela B Ramos
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Rosalind A Coleman
- Department of Nutrition, University of North Carolina, Chapel Hill, NC 27599, USA
| | - Katia C Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
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29
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Lipovšek S, Novak T. Autophagy in the fat body cells of the cave cricket Troglophilus neglectus Krauss, 1878 (Rhaphidophoridae, Saltatoria) during overwintering. PROTOPLASMA 2016; 253:457-466. [PMID: 25956501 DOI: 10.1007/s00709-015-0824-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Accepted: 04/24/2015] [Indexed: 06/04/2023]
Abstract
The cave cricket Troglophilus neglectus regularly overwinters for 4-5 months in hypogean habitats. Winter dormancy is a natural starvation period, providing the opportunity to study autophagy under natural conditions. We aimed to evaluate the autophagic activity in adipocytes and urocytes of the fat body in three time frames: directly before overwintering, in the middle of dormancy, and at its end. For this purpose, we sampled individuals in caves. The cell ultrastructure was studied by transmission electron microscopy (TEM) and the abundance of autophagosomes by immunofluorescence microscopy (IFM), applying the widely used, specific immunolabeling marker microtubule-associated protein 1 light chain 3 (LC3). Before overwintering, TEM revealed scarce autophagosomes and residual bodies in the adipocytes and none in the urocytes. Congruently, IFM showed a very limited or no reaction. In the middle and at the end of overwintering, in both cell types, phagophores, autophagosomes, autolysosomes, and residual bodies were identified by TEM, while LC3 immunolabeling for detecting autophagosomes showed a conspicuous positive reaction. Both methods revealed that there were no significant differences between the sexes in any time frame. Minimal autophagic activity was detected before the winter dormancy, and it gradually intensified till the end of overwintering, probably because reserve proteins in protein granula are not composed of all the required amino acids. We conclude that in T. neglectus, autophagy is a substantial response to starvation and supports homeostatic processes during winter dormancy by supplying cells with nutrients.
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Affiliation(s)
- Saška Lipovšek
- Faculty of Medicine, University of Maribor, Taborska ulica 8, 2000, Maribor, Slovenia.
- Department of Biology, Faculty of Natural Sciences and Mathematics, University of Maribor, Koroška 160, 2000, Maribor, Slovenia.
- Faculty of Chemistry and Chemical Engineering, University of Maribor, Smetanova ulica 17, 2000, Maribor, Slovenia.
| | - Tone Novak
- Department of Biology, Faculty of Natural Sciences and Mathematics, University of Maribor, Koroška 160, 2000, Maribor, Slovenia
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Alves-Bezerra M, De Paula IF, Medina JM, Silva-Oliveira G, Medeiros JS, Gäde G, Gondim KC. Adipokinetic hormone receptor gene identification and its role in triacylglycerol metabolism in the blood-sucking insect Rhodnius prolixus. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2016; 69:51-60. [PMID: 26163435 DOI: 10.1016/j.ibmb.2015.06.013] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Revised: 06/22/2015] [Accepted: 06/23/2015] [Indexed: 06/04/2023]
Abstract
Adipokinetic hormone (AKH) has been associated with the control of energy metabolism in a large number of arthropod species due to its role on the stimulation of lipid, carbohydrate and amino acid mobilization/release. In the insect Rhodnius prolixus, a vector of Chagas' disease, triacylglycerol (TAG) stores must be mobilized to sustain the metabolic requirements during moments of exercise or starvation. Besides the recent identification of the R. prolixus AKH peptide, other components required for the AKH signaling cascade and its mode of action remain uncharacterized in this insect. In the present study, we identified and investigated the expression profile of the gene encoding the AKH receptor of R. prolixus (RhoprAkhr). This gene is highly conserved in comparison to other sequences already described and its transcript is abundant in the fat body and the flight muscle of the kissing bug. Moreover, RhoprAkhr expression is induced in the fat body at moments of increased TAG mobilization; the knockdown of this gene resulted in TAG accumulation both in fat body and flight muscle after starvation. The inhibition of Rhopr-AKHR transcription as well as the treatment of insects with the peptide Rhopr-AKH in its synthetic form altered the transcript levels of two genes involved in lipid metabolism, the acyl-CoA-binding protein-1 (RhoprAcbp1) and the mitochondrial glycerol-3-phosphate acyltransferase-1 (RhoprGpat1). These results indicate that the AKH receptor is regulated at transcriptional level and is required for TAG mobilization under starvation. In addition to the classical view of AKH as a direct regulator of enzymatic activity, we propose here that AKH signaling may account for the regulation of nutrient metabolism by affecting the expression profile of target genes.
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Affiliation(s)
- Michele Alves-Bezerra
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Iron F De Paula
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Jorge M Medina
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gleidson Silva-Oliveira
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Jonas S Medeiros
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gerd Gäde
- Department of Biological Sciences, University of Cape Town, John Day Building, Rondebosch ZA-7701, South Africa
| | - Katia C Gondim
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
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Mustonen AM, Käkelä R, Paakkonen T, Nieminen P. Life stage-related differences in fatty acid composition of an obligate ectoparasite, the deer ked (Lipoptena cervi)-influence of blood meals and gender. Comp Biochem Physiol A Mol Integr Physiol 2014; 179:62-70. [PMID: 25223709 DOI: 10.1016/j.cbpa.2014.09.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 09/03/2014] [Accepted: 09/03/2014] [Indexed: 10/24/2022]
Abstract
Metamorphosis and diet often influence fatty acid (FA) signatures (FAS) of insects. We investigated FAS in a hematophagous ectoparasite, the deer ked (Lipoptena cervi). Deer keds shed their wings upon attachment on the host and, thus, the FAS of an individual blood-fed imago/pupa in the fur of its host can be traced back to the blood FA profile of a single moose (Alces alces). Host blood and different life stages of deer keds were investigated for FA by gas chromatography. The FAS of life stages resembled each other more closely than the diet. Blood meals modified the FAS of both sexes but the FAS of the blood-fed females were closer to those of the prepupae/pupae. The parasitizing males had higher proportions of major saturated FA (SFA) and polyunsaturated FA (PUFA) than the females, which contained more monounsaturated FA (MUFA) with higher ratios of n-3/n-6 PUFA and unsaturated FA (UFA)/SFA. The proportions of 16:1n-7 were <1% in the blood but 18% (males) and 29% (females) in the blood-fed keds. Allocation of lipids to offspring by the females and possible accumulation of PUFA in male reproductive organs may have induced these sex-related differences. MUFA percentages and UFA/SFA ratios increased while SFA and many PUFA decreased from the reproducing females to the pupae. The diapausing pupae displayed lowered n-3/n-6 PUFA ratios and could have mobilized 16:0 and 18:3n-3 for the most fundamental metabolic processes. In conclusion, FAS are modified through the life stages of the deer ked possibly due to their different FA requirements.
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Affiliation(s)
- Anne-Mari Mustonen
- University of Eastern Finland, Faculty of Science and Forestry, Department of Biology, P.O. Box 111, FI-80101 Joensuu, Finland; University of Eastern Finland, Faculty of Health Sciences, School of Medicine, Institute of Biomedicine/Anatomy, P.O. Box 1627, FI-70211 Kuopio, Finland.
| | - Reijo Käkelä
- University of Helsinki, Faculty of Biological and Environmental Sciences, Department of Biosciences, P.O. Box 65, FI-00014 University of Helsinki, Finland
| | - Tommi Paakkonen
- University of Eastern Finland, Faculty of Science and Forestry, Department of Biology, P.O. Box 111, FI-80101 Joensuu, Finland; University of Eastern Finland, Faculty of Health Sciences, School of Medicine, Institute of Biomedicine/Anatomy, P.O. Box 1627, FI-70211 Kuopio, Finland
| | - Petteri Nieminen
- University of Eastern Finland, Faculty of Science and Forestry, Department of Biology, P.O. Box 111, FI-80101 Joensuu, Finland; University of Eastern Finland, Faculty of Health Sciences, School of Medicine, Institute of Biomedicine/Anatomy, P.O. Box 1627, FI-70211 Kuopio, Finland
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Toprak U, Guz N, Gurkan MO, Hegedus DD. Identification and coordinated expression of perilipin genes in the biological cycle of sunn pest, Eurygaster maura (Hemiptera: Scutelleridae): Implications for lipolysis and lipogenesis. Comp Biochem Physiol B Biochem Mol Biol 2014; 171:1-11. [DOI: 10.1016/j.cbpb.2014.02.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2013] [Revised: 01/30/2014] [Accepted: 02/05/2014] [Indexed: 01/10/2023]
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Azeez OI, Meintjes R, Chamunorwa JP. Fat body, fat pad and adipose tissues in invertebrates and vertebrates: the nexus. Lipids Health Dis 2014; 13:71. [PMID: 24758278 PMCID: PMC4005007 DOI: 10.1186/1476-511x-13-71] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 04/14/2014] [Indexed: 12/13/2022] Open
Abstract
The fat body in invertebrates was shown to participate in energy storage and homeostasis, apart from its other roles in immune mediation and protein synthesis to mention a few. Thus, sharing similar characteristics with the liver and adipose tissues in vertebrates. However, vertebrate adipose tissue or fat has been incriminated in the pathophysiology of metabolic disorders due to its role in production of pro-inflammatory cytokines. This has not been reported in the insect fat body. The link between the fat body and adipose tissue was examined in this review with the aim of determining the principal factors responsible for resistance to inflammation in the insect fat body. This could be the missing link in the prevention of metabolic disorders in vertebrates, occasioned by obesity.
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Affiliation(s)
- Odunayo Ibraheem Azeez
- Department of Anatomy and Physiology, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort 0110 Pretoria, South Africa
- Department of Veterinary Physiology, Biochemistry and Pharmacology, Faculty of Veterinary Medicine, University of Ibadan, Ibadan, Nigeria
| | - Roy Meintjes
- Department of Anatomy and Physiology, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort 0110 Pretoria, South Africa
| | - Joseph Panashe Chamunorwa
- Department of Anatomy and Physiology, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort 0110 Pretoria, South Africa
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Entringer PF, Grillo LAM, Pontes EG, Machado EA, Gondim KC. Interaction of lipophorin with Rhodnius prolixus oocytes: biochemical properties and the importance of blood feeding. Mem Inst Oswaldo Cruz 2013; 108:836-44. [PMID: 24037104 PMCID: PMC3970653 DOI: 10.1590/0074-0276130129] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Indexed: 11/11/2023] Open
Abstract
Lipophorin (Lp) is the main haemolymphatic lipoprotein in insects and transports lipids between different organs. In adult females, lipophorin delivers lipids to growing oocytes. In this study, the interaction of this lipoprotein with the ovaries of Rhodnius prolixus was characterised using an oocyte membrane preparation and purified radiolabelled Lp (125I-Lp). Lp-specific binding to the oocyte membrane reached equilibrium after 40-60 min and when 125I-Lp was incubated with increasing amounts of membrane protein, corresponding increases in Lp binding were observed. The specific binding of Lp to the membrane preparation was a saturable process, with a K(d) of 7.1 ± 0.9 x 10-8M and a maximal binding capacity of 430 ± 40 ng 125I-Lp/µg of membrane protein. The binding was calcium independent and pH sensitive, reaching its maximum at pH 5.2-5.7. Suramin inhibited the binding interaction between Lp and the oocyte membranes, which was completely abolished at 0.5 mM suramin. The oocyte membrane preparation from R. prolixus also showed binding to Lp from Manduca sexta. When Lp was fluorescently labelled and injected into vitellogenic females, the level of Lp-oocyte binding was much higher in females that were fed whole blood than in those fed blood plasma.
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Affiliation(s)
- Petter Franco Entringer
- Instituto de Bioquímica Médica
- Laboratório de Imunoparasitologia, Centro de Pesquisas Gonçalo Moniz-Fiocruz, Salvador, BA, Brasil
| | | | - Emerson Guedes Pontes
- Instituto de Bioquímica Médica
- Departamento de Química, Instituto de Ciências Exatas, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ, Brasil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular
| | - Ednildo Alcântara Machado
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular
| | - Katia Calp Gondim
- Instituto de Bioquímica Médica
- Instituto Nacional de Ciência e Tecnologia em Entomologia Molecular
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Triacylglycerol biosynthesis occurs via the glycerol-3-phosphate pathway in the insect Rhodnius prolixus. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1821:1462-71. [DOI: 10.1016/j.bbalip.2012.08.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 07/21/2012] [Accepted: 08/02/2012] [Indexed: 11/17/2022]
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Neutral lipid composition changes in the fat bodies of engorged females Rhipicephalus microplus ticks in response to fungal infections. Parasitol Res 2012; 112:501-9. [PMID: 23138474 DOI: 10.1007/s00436-012-3159-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Accepted: 09/28/2012] [Indexed: 10/27/2022]
Abstract
The tick's fat body plays an essential role in energy storage and utilization. This study aimed to analyze the fat body neutral lipid composition in Rhipicephalus microplus engorged females. In the first study (physiological profile of untreated ticks), the lipid analysis took place over the course of 4 days; the engorged females were incubated at optimal conditions and their fat bodies were dissected daily. Fat body lipid analysis after fungal infection with Metarhizium anisopliae sensu lato (s.l.) or Beauveria bassiana s.l. was performed with four groups: one without any treatment, one that was inoculated with a solution of 0.1 % Tween 80 in water, and two groups that were inoculated with M. anisopliae or B. bassiana conidial suspensions. The fat bodies were dissected 24 and 48 h after infection. Lipid analysis was conducted by thin-layer chromatography on a silica plate. The results of the physiological profile showed that the amounts of triacylglycerol (TAG) and free cholesterol (CHO) decreased with time, whereas cholesterol ester (CHOE) increased on the second and fourth days. Following M. anisopliae or B. bassiana infection, there was an increase in the amount of CHO after 24 h, whereas the other lipid classes were not altered. M. anisopliae caused an increase in CHOE and TAG and a reduction in CHO at 48 h after infection; however, B. bassiana infection did not cause significant alterations in the concentrations of these lipids. M. anisopliae and B. bassiana infection changed the fat body metabolism of engorged female R. microplus ticks. This study provides the first report of changes in the neutral lipid composition of the R. microplus fat body.
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Majerowicz D, Alves-Bezerra M, Logullo R, Fonseca-de-Souza AL, Meyer-Fernandes JR, Braz GRC, Gondim KC. Looking for reference genes for real-time quantitative PCR experiments in Rhodnius prolixus (Hemiptera: Reduviidae). INSECT MOLECULAR BIOLOGY 2011; 20:713-722. [PMID: 21929722 DOI: 10.1111/j.1365-2583.2011.01101.x] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Quantitative real-time PCR (qPCR) has become one of the most used techniques to measure gene expression. However, normalization of gene expression data against reference genes is essential, although these are usually used without any kind of validation. The expression of seven genes was compared in organs of Rhodnius prolixus under diverse conditions, using published software to test gene expression stability. Rp18S and elongation factor 1 (RpEF -1) were the most reliable genes for normalization in qPCR when gene expression in different organs was compared. Moreover, both genes were found to be the best references when transcript levels were compared in the posterior midgut of insects infected with Trypanosoma cruzi. Rp18S was also the best reference gene in the fat bodies of unfed and fed insects. By contrast, RpEF-1 was found to be the best reference gene for comparison between posterior midguts, and RpMIP or RpActin should be used to compare gene expression in the ovaries. Although Rp18S is indicated here as the best reference in most cases, reports from the literature show that it is difficult to find an optimum reference gene. Nevertheless, validation of candidate genes to be taken as references is important when new experimental conditions are tested to avoid incorrect data interpretation.
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Affiliation(s)
- D Majerowicz
- Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho 373, Ilha do Fundão, Rio de Janeiro, RJ, Brazil.
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38
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Benoit JB, Yang G, Krause TB, Patrick KR, Aksoy S, Attardo GM. Lipophorin acts as a shuttle of lipids to the milk gland during tsetse fly pregnancy. JOURNAL OF INSECT PHYSIOLOGY 2011; 57:1553-61. [PMID: 21875592 PMCID: PMC3209505 DOI: 10.1016/j.jinsphys.2011.08.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2011] [Revised: 08/05/2011] [Accepted: 08/08/2011] [Indexed: 05/09/2023]
Abstract
During pregnancy in the viviparous tsetse fly, lipid mobilization is essential for the production of milk to feed the developing intrauterine larva. Lipophorin (Lp) functions as the major lipid transport protein in insects and closely-related arthropods. In this study, we assessed the role of Lp and the lipophorin receptor (LpR) in the lipid mobilization process during tsetse reproduction. We identified single gene sequences for GmmLp and GmmLpR from the genome of Glossinamorsitansmorsitans, and measured spatial and temporal expression of gmmlp and gmmlpr during the female reproductive cycle. Our results show that expression of gmmlp is specific to the adult fat body and larvae. In the adult female, gmmlp expression is constitutive. However transcript levels increase in the larva as it matures within the mother's uterus, reaching peak expression just prior to parturition. GmmLp was detected in the hemolymph of pregnant females and larvae, but not in the uterine fluid or larval gut contents ruling out the possibility of direct transfer of GmmLp from mother to offspring. Transcripts for gmmlpr were detected in the head, ovaries, midgut, milk gland/fat body, ovaries and developing larva. Levels of gmmlpr remain stable throughout the first and second gonotrophic cycles with a slight dip observed during the first gonotrophic cycle. GmmLpR was detected in multiple tissues, including the midgut, fat body, milk gland, spermatheca and head. Knockdown of gmmlp by RNA interference resulted in reduced hemolymph lipid levels, delayed oocyte development and extended larval gestation. Similar suppresion of gmmlpr did not significantly reduce hemolymph lipid levels or oogenesis duration, but did extend the duration of larval development. Thus, GmmLp function as the primary shuttle for lipids originating from the midgut and fat body to the ovaries and milk gland to supply resources for developing oocytes and larval nourishment, respectively. Once in the milk gland however, lipids are apparently transferred into the developing larva not by lipophorin but by another carrier lipoprotein.
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Affiliation(s)
- Joshua B. Benoit
- Division of Epidemiology of Microbial Diseases, School of Public Health, Yale University, New Haven, CT 06511
| | - Guangxiao Yang
- Division of Epidemiology of Microbial Diseases, School of Public Health, Yale University, New Haven, CT 06511
- Department of Pathology, Yale University School of Medicine, New Haven, CT 06520
| | - Tyler B. Krause
- Division of Epidemiology of Microbial Diseases, School of Public Health, Yale University, New Haven, CT 06511
| | - Kevin R. Patrick
- Division of Epidemiology of Microbial Diseases, School of Public Health, Yale University, New Haven, CT 06511
| | - Serap Aksoy
- Corresponding author Serap Aksoy, 60 College Street, Division of Epidemiology of Microbial Diseases, School of Public Health, Yale University, New Haven, CT 06511,
| | - Geoffrey M. Attardo
- Division of Epidemiology of Microbial Diseases, School of Public Health, Yale University, New Haven, CT 06511
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Santos R, Rosas-Oliveira R, Saraiva FB, Majerowicz D, Gondim KC. Lipid accumulation and utilization by oocytes and eggs of Rhodnius prolixus. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2011; 77:1-16. [PMID: 21308762 DOI: 10.1002/arch.20414] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Insect eggs must contain the necessary nutrients for embryonic growth. In this article, we investigated the accumulation of triacylglycerol (TAG) in growing oocytes and its utilization during embryonic development. TAG makes up about 60% of the neutral lipids in oocytes and accumulates as oocytes grow, from 2.2 ± 0.1 µg in follicles containing 1.0 mm length oocytes to 10.2 ± 0.8 µg in 2.0 mm length oocytes. Lipophorin (Lp), the hemolymphatic lipoprotein, radioactively labeled in free fatty acid (FFA) or diacylglycerol (DAG), was used to follow the transport of these lipids to the ovary. Radioactivity from both lipid classes accumulated in the oocytes, which was abolished at 4°C. The capacity of the ovary to receive FFA or DAG from Lp varied according to time after a blood meal and reached a maximum around the second day. (3) H-DAG supplied by Lp to the ovaries was used in the synthesis of TAG as, 48 hr after injection, most of the radioactivity was found in TAG (85.7% of labeling in neutral lipids). During embryogenesis, lipid stores were mobilized, and the TAG content decreased from 16.4 ± 2.1 µg/egg on the first day to 10.0 ± 1.3 µg on day 15, just before hatching. Of these, 7.4 ± 0.9 µg were found in the newly emerged nymphs. In unfertilized eggs, the TAG content did not change. Although the TAG content decreased during embryogenesis, the relative lipid composition of the egg did not change. The amount of TAG in the nymph slowly decreased during the days after hatching.
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Affiliation(s)
- Rachel Santos
- Instituto de Bioquímica Médica, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
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40
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Fruttero LL, Frede S, Rubiolo ER, Canavoso LE. The storage of nutritional resources during vitellogenesis of Panstrongylus megistus (Hemiptera: Reduviidae): the pathways of lipophorin in lipid delivery to developing oocytes. JOURNAL OF INSECT PHYSIOLOGY 2011; 57:475-486. [PMID: 21277855 DOI: 10.1016/j.jinsphys.2011.01.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2010] [Revised: 01/18/2011] [Accepted: 01/19/2011] [Indexed: 05/30/2023]
Abstract
In this work, we have analyzed the pathways by which lipophorin (Lp) delivers its lipid cargo to developing oocytes of Panstrongylus megistus, a hematophagous vector of Chagas' disease. Lp, vitellin, total lipids and proteins were measured in ovarian tissues at different stages of the reproductive cycle. Localization of Lp in developing oocytes, mainly at their cortical area, was demonstrated by immunofluorescence assays using an anti-Lp antibody labeled with FITC. In vivo approaches injecting fluorescently labeled Lp to follow the course of the entire particle (Lp-DiI or Lp-Oregon Green) or its lipid cargo (Lp-Bodipy-FA) were monitored by laser scanning confocal microscopy. Significant increases in the amounts of lipids, proteins and vitellin were observed in ovarian tissue with the progress of vitellogenesis. Unexpectedly, an increase in the amount of Lp was also observed. The experiments in vivo demonstrated that the uptake of fluorescent Lp labeled on its protein or lipid moiety by developing oocytes occurred very fast, being impaired at low temperatures. The co-injection of fluorescent Lp and vitellogenin (Vg) showed that both particles co-localized inside yolk bodies, confirming the endocytic pathway for Lp. When the fate of lipids transferred to oocytes was evaluated in vitellogenic females by co-injecting Lp-Bodipy-FA and Lp-DiI, the signal for Bodipy-FA was found in both lipid droplets and yolk bodies. In contrast, in injected females kept at 4°C the fluorescence was reduced, being observed exclusively in lipid droplets, implying that lipid transfer to the oocyte was diminished but not abolished. Taken together, the results demonstrate that in the hematophagous P. megistus, the storage of lipid resources by developing oocytes occurs by the convergence of different pathways by which Lp maximizes the delivery of its lipid cargo. In addition, it was also shown that, to some extent, lipids stored in the oocyte lipid droplets can also originate from endocytosed Vg. The relevance of these events in the context of the physiology of reproduction in P. megistus is discussed.
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Affiliation(s)
- Leonardo L Fruttero
- Departamento de Bioquímica Clínica, Centro de Investigaciones en Bioquímica Clínica e Inmunología, Facultad de Ciencias Químicas-Universidad Nacional de Córdoba, Córdoba, CP 5000, Argentina
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Lipovšek S, Novak T, Janžekovič F, Pabst MA. Role of the fat body in the cave crickets Troglophilus cavicola and Troglophilus neglectus (Rhaphidophoridae, Saltatoria) during overwintering. ARTHROPOD STRUCTURE & DEVELOPMENT 2011; 40:54-63. [PMID: 20868768 DOI: 10.1016/j.asd.2010.09.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2010] [Revised: 09/09/2010] [Accepted: 09/10/2010] [Indexed: 05/29/2023]
Abstract
The cave crickets Troglophilus cavicola and Troglophilus neglectus are the most widely distributed European species of the family Rhaphidophoridae. Their life cycles span two years. They overwinter twice in caves in 4-6 months lasting diapause, T. cavicola in warmer microhabitats. In caves, older T. cavicola undergo sexual maturation, while T. neglectus do not. We hypothesized that the use of energy-supplying compounds and reserve proteins in the fat body is more extensive in T. cavicola than in T. neglectus. We analyzed the contents and morphology of lipid droplets, glycogen rosettes and protein granula at the beginning, the middle and the end of overwintering applying optic, TEM and biochemical methods. In all individuals, the fat body is composed of about 40 oval ribbons consisted of gradually changing adipocytes and urocytes. T. cavicola use glycogen continuously, and stop using lipids in the middle of overwintering, while this is inverse in T. neglectus. Till the middle of overwintering, all individuals exploit proteins, afterwards they are unevenly exploited. We found that the fat body is differently engaged in metabolism of both cave crickets during overwintering, supporting a more glycogen-dependent metabolism in T. cavicola, and a more lipid-dependent one in T. neglectus.
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Affiliation(s)
- Saška Lipovšek
- Medical Faculty, University of Maribor, Slomškov trg 15, Maribor, Slovenia.
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Ferreira LL, Lorenzo MG, Elliot SL, Guarneri AA. A standardizable protocol for infection of Rhodnius prolixus with Trypanosoma rangeli, which mimics natural infections and reveals physiological effects of infection upon the insect. J Invertebr Pathol 2010; 105:91-7. [PMID: 20546751 DOI: 10.1016/j.jip.2010.05.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2010] [Revised: 05/05/2010] [Accepted: 05/18/2010] [Indexed: 10/19/2022]
Abstract
Trypanosoma rangeli is a protozoan parasite that shares hosts - mammals and triatomines - with Trypanosoma cruzi, the etiological agent of Chagas disease. Although T. rangeli is customarily considered to be non-pathogenic to human hosts, it is able to produce pathologies in its invertebrate hosts. However, advances are hindered by a lack of standardization of infection procedures and these pathologies need documentation. To establish a suitable, and standardizable, infection protocol, the duration of the fourth instar was evaluated in nymphs infected by injection into the thorax with different concentrations of parasites, and compared with nymphs infected naturally (i.e. orally). We demonstrate that delays in moult were attributable to the presence of the parasite in the haemolymph (vs. the gut) and propose that the protocol presented here simulates closely natural infections. This methodology was then used for the evaluation of physiological parameters and several hitherto unreported effects of T. rangeli infection on Rhodnius prolixus were revealed. Haemolymph volume was greater in infected than uninfected nymphs but this alteration could not be attributed to water retention, since infected insects lost the same amount of water as controls. However, we found that lipid content and fat body weight were both increased in insects infected by T. rangeli. We propose that this is due to the parasite's sequestration of host blood lipids and carrier proteins. With these findings, we have taken a few first steps to unravelling physiological details of the host-parasite interaction. We suggest future directions towards a fuller understanding of mechanistic and adaptive aspects of triatomine-trypanosomatid interactions.
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Abstract
The fat body plays major roles in the life of insects. It is a dynamic tissue involved in multiple metabolic functions. One of these functions is to store and release energy in response to the energy demands of the insect. Insects store energy reserves in the form of glycogen and triglycerides in the adipocytes, the main fat body cell. Insect adipocytes can store a great amount of lipid reserves as cytoplasmic lipid droplets. Lipid metabolism is essential for growth and reproduction and provides energy needed during extended nonfeeding periods. This review focuses on energy storage and release and summarizes current understanding of the mechanisms underlying these processes in insects.
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