Identification and Functional Analysis of Adipokinetic Hormone Receptor in Ostrinia furnacalis Guenée Larvae Parasitized by Macrocentrus cingulum.

As a typical G protein-coupled receptor, the adipokinetic hormone receptor (AKHR) has seven transmembrane domains (TMDs), and its structure and function are similar to the gonadotropin-releasing hormone receptor (GnRHR) in vertebrates. However, there is a dearth of information on other components of the AKHR signaling pathway and how it functions in the interaction between insect hosts and parasitoids. In this study, we cloned and analyzed the multifunctional Ostrinia furnacalis AKHR (OfAKHR) cDNA (GenBank accession number MF797868). OfAKHR has a 2206 bp full-length cDNA, which includes an open reading frame containing 1194 bp. OfAKHR contains the typical seven TMDs, and a "DRY" motif. OfAKHR has the highest relative expression in the fat body and the fifth instar larvae. The results revealed that ApoLpⅢ, PPO2, GS, TPS, Cecropin, and Moricin decreased the transcription levels from 48 to 72 h after the knockdown of OfAKHR expression by dsOfAKHR injection in the fourth instar O. furnacalis larvae. The parasitization of Macrocentrus cingulum selectively upregulated the expression levels of nutrition metabolism and immune-related genes in parasitized O. furnacalis larvae, stimulated lysozyme activity, and obviously raised the concentrations of triglyceride and trehalose in the hemolymph of O. furnacalis larvae. However, they inhibited the activities of PO and trehalase. This study is conducive to a deeper cognition of the roles of OfAKHR in nutrition and immune homeostasis, coevolution, and coexistence between parasitic wasps and hosts. It also sheds light on the potential as the target of pest control reagents.

Analysis of Active Components and Transcriptome of Freesia refracta Callus Extract and Its Effects against Oxidative Stress and Wrinkles in Skin.

Freesia refracta (FR), a perennial flower of the Iris family (Iridaceae), is widely used in cosmetics despite limited scientific evidence of its skin benefits and chemical composition, particularly of FR callus extract (FCE). This study identified biologically active compounds in FCE and assessed their skin benefits, focusing on anti-aging. FR calli were cultured, extracted with water at 40 °C, and analyzed using Centrifugal Partition Chromatography (CPC), Nuclear Magnetic Resonance (NMR), and HCA, revealing key compounds, namely nicotinamide and pyroglutamic acid. FCE significantly increased collagen I production by 52% in normal and aged fibroblasts and enhanced fibroblast-collagen interaction by 37%. An in vivo study of 43 female volunteers demonstrated an 11.1% reduction in skin roughness and a 2.3-fold increase in collagen density after 28 days of cream application containing 3% FCE. Additionally, the preservation tests of cosmetics containing FCE confirmed their stability over 12 weeks. These results suggest that FCE offers substantial anti-aging benefits by enhancing collagen production and fibroblast-collagen interactions. These findings highlighted the potential of FCE in cosmetic applications, providing significant improvements in skin smoothness and overall appearance. This study fills a gap in the scientific literature regarding the skin benefits and chemical composition of FR callus extract, supporting its use in the development of effective cosmeceuticals.

Adipokinetic hormone signaling mediates the enhanced fecundity of Diaphorina citri infected by 'Candidatus Liberibacter asiaticus'.

Diaphorina citri serves as the primary vector for 'Candidatus Liberibacter asiaticus (CLas),' the bacterium associated with the severe Asian form of huanglongbing. CLas-positive D. citri are more fecund than their CLas-negative counterparts and require extra energy expenditure. Therefore, understanding the molecular mechanisms linking metabolism and reproduction is of particular importance. In this study, we found adipokinetic hormone (DcAKH) and its receptor (DcAKHR) were essential for increasing lipid metabolism and fecundity in response to CLas infection in D. citri. Knockdown of DcAKH and DcAKHR not only resulted in the accumulation of triacylglycerol and a decline of glycogen, but also significantly decreased fecundity and CLas titer in ovaries. Combined in vivo and in vitro experiments showed that miR-34 suppresses DcAKHR expression by binding to its 3' untranslated region, whilst overexpression of miR-34 resulted in a decline of DcAKHR expression and CLas titer in ovaries and caused defects that mimicked DcAKHR knockdown phenotypes. Additionally, knockdown of DcAKH and DcAKHR significantly reduced juvenile hormone (JH) titer and JH signaling pathway genes in fat bodies and ovaries, including the JH receptor, methoprene-tolerant (DcMet), and the transcription factor, Krüppel homolog 1 (DcKr-h1), that acts downstream of it, as well as the egg development related genes vitellogenin 1-like (DcVg-1-like), vitellogenin A1-like (DcVg-A1-like) and the vitellogenin receptor (DcVgR). As a result, CLas hijacks AKH/AKHR-miR-34-JH signaling to improve D. citri lipid metabolism and fecundity, while simultaneously increasing the replication of CLas, suggesting a mutualistic interaction between CLas and D. citri ovaries.

A robust ultra-performance liquid chromatography-tandem mass spectrometry method for simultaneous determination of 10 components in glutathione cycle.

Glutathione (GSH) is an important antioxidant that is generated and degraded via the GSH cycle. Quantification of the main components in the GSH cycle is necessary to evaluate the process of GSH. In this study, a robust ultra-performance liquid chromatography-tandem mass spectrometry method for the simultaneous quantification of 10 components (GSH; γ-glutamylcysteine; cysteinyl-glycine; n-acetylcysteine; homocysteine; cysteine; cystine; methionine; glutamate; pyroglutamic acid) in GSH cycle was developed. The approach was optimized in terms of derivative, chromatographic, and spectrometric conditions as well as sample preparation. The unstable thiol groups of GSH, γ-glutamylcysteine, cysteinyl-glycine, n-acetylcysteine, cysteine, and homocysteine were derivatized by n-ethylmaleimide. The derivatized and underivatized analytes were separated on an amino column with gradient elution. The method was further validated in terms of selectivity (no interference), linearity (R2 > 0.99), precision (% relative standard deviation [RSD%] range from 0.57 to 10.33), accuracy (% relative error [RE%] range from -3.42 to 10.92), stability (RSD% < 5.68, RE% range from -2.54 to 4.40), recovery (RSD% range from 1.87 to 7.87) and matrix effect (RSD% < 5.42). The validated method was applied to compare the components in the GSH cycle between normal and oxidative stress cells, which would be helpful in clarifying the effect of oxidative stress on the GSH cycle.

Compensatory enhancement of input maintains aversive dopaminergic reinforcement in hungry Drosophila.

Hungry animals need compensatory mechanisms to maintain flexible brain function, while modulation reconfigures circuits to prioritize resource seeking. In Drosophila, hunger inhibits aversively reinforcing dopaminergic neurons (DANs) to permit the expression of food-seeking memories. Multitasking the reinforcement system for motivation potentially undermines aversive learning. We find that chronic hunger mildly enhances aversive learning and that satiated-baseline and hunger-enhanced learning require endocrine adipokinetic hormone (AKH) signaling. Circulating AKH influences aversive learning via its receptor in four neurons in the ventral brain, two of which are octopaminergic. Connectomics revealed AKH receptor-expressing neurons to be upstream of several classes of ascending neurons, many of which are presynaptic to aversively reinforcing DANs. Octopaminergic modulation of and output from at least one of these ascending pathways is required for shock- and bitter-taste-reinforced aversive learning. We propose that coordinated enhancement of input compensates for hunger-directed inhibition of aversive DANs to preserve reinforcement when required.

The tick Ixodes scapularis has five different GPCRs specifically activated by ACP (adipokinetic hormone/corazonin-related peptide).

Insects have about 50 neuropeptide genes and about 70 genes, coding for neuropeptide G protein-coupled receptors (GPCRs). An important, but small family of evolutionarily related insect neuropeptides consists of adipokinetic hormone (AKH), corazonin, and AKH/corazonin-related peptide (ACP). Normally, insects have one specific GPCR for each of these neuropeptides. The tick Ixodes scapularis is not an insect, but belongs to the subphylum Chelicerata, which comprises ticks, scorpions, mites, spiders, and horseshoe crabs. Many of the neuropeptides and neuropeptide GPCRs occurring in insects, also occur in chelicerates, illustrating that insects and chelicerates are evolutionarily closely related. The tick I. scapularis is an ectoparasite and health risk for humans, because it infects its human host with dangerous pathogens during a blood meal. Understanding the biology of ticks will help researchers to prevent tick-borne diseases. By annotating the I. scapularis genome sequence, we previously found that ticks contain as many as five genes, coding for presumed ACP receptors. In the current paper, we cloned these receptors and expressed each of them in Chinese Hamster Ovary (CHO) cells. Each expressed receptor was activated by nanomolar concentrations of ACP, demonstrating that all five receptors were functional ACP receptors. Phylogenetic tree analyses showed that the cloned tick ACP receptors were mostly related to insect ACP receptors and, next, to insect AKH receptors, suggesting that ACP receptor genes and AKH receptor genes originated by gene duplications from a common ancestor. Similar duplications have probably occurred for the ligand genes, during a process of ligand/receptor co-evolution. Interestingly, chelicerates, in contrast to all other arthropods, do not have AKH or AKH receptor genes. Therefore, the ancestor of chelicerates might have lost AKH and AKH receptor genes and functionally replaced them by ACP and ACP receptor genes. For the small family of AKH, ACP, and corazonin receptors and their ligands, gene losses and gene gains occur frequently between the various ecdysozoan clades. Tardigrades, for example, which are well known for their survival in extreme environments, have as many as ten corazonin receptor genes and six corazonin peptide genes, while insects only have one of each, or none.

Expression of brain-derived neurotrophic factor and formation of migrasome increases in the glioma cells induced by the adipokinetic hormone.

OBJECTIVE: It has been previously shown that brain-derived neurotrophic factor is linked with various types of cancer. Brain-derived neurotrophic factor is found to be highly expressed in multiple human cancers and associated with tumor growth, invasion, and metastasis. Adipokinetic hormones are functionally related to the vertebrate glucagon, as they have similar functionalities that manage the nutrient-dependent secretion of these two hormones. Migrasomes are new organelles that contain numerous small vesicles, which aid in transmitting signals between the migrating cells. Therefore, the aim of this study was to investigate the effects of Anax imperator adipokinetic hormone on brain-derived neurotrophic factor expression and ultrastructure of cells in the C6 glioma cell line. METHODS: The rat C6 glioma cells were treated with concentrations of 5 and 10 Anax imperator adipokinetic hormone for 24 h. The effects of the Anax imperator adipokinetic hormone on the migrasome formation and brain-derived neurotrophic factor expression were analyzed using immunocytochemistry and transmission electron microscope. RESULTS: The rat C6 glioma cells of the 5 and 10 µM Anax imperator adipokinetic hormone groups showed significantly high expressions of brain-derived neurotrophic factor and migrasomes numbers, compared with the control group. CONCLUSION: A positive correlation was found between the brain-derived neurotrophic factor expression level and the formation of migrasome, which indicates that the increased expression of brain-derived neurotrophic factor and the number of migrasomes may be involved to metastasis of the rat C6 glioma cell line induced by the Anax imperator adipokinetic hormone. Therefore, the expression of brain-derived neurotrophic factor and migrasome formation may be promising targets for preventing tumor proliferation, invasion, and metastasis in glioma.

Pyroglutamylation modulates electronic properties and the conformational ensemble of the amyloid ß-peptide.

Alzheimer's disease (AD) is a neurodegenerative disorder that is characterized by the formation of extracellular amyloid-ß (Aß) plaques. The underlying cause of AD is unknown, however, post-translational modifications (PTMs) of Aß have been found in AD patients and are thought to play a role in protein aggregation. One such PTM is pyroglutamylation, which can occur at two sites in Aß, Glu3 and Glu11. This modification of Aß involves the truncation and charge-neutralization of N-terminal glutamate, causing Aß to become more hydrophobic and prone to aggregation. The molecular mechanism by which the introduction of pyroglutamate (pE) promotes aggregation has not been determined. To gain a greater understanding of the role that charge neutralization and truncation of the N-terminus plays on Aß conformational sampling, we used the Drude polarizable force field (FF) to perform molecular dynamics simulations on AßpE3-42 and AßpE11-42 and comparing their properties to previous simulations of Aß1-42. The Drude polarizable FF allows for a more accurate representation of electrostatic interactions, therefore providing novel insights into the role that charge plays in protein dynamics. Here, we report the parametrization of pE in the Drude polarizable FF and the effect of pyroglutamylation on Aß. We found that AßpE3-42 and AßpE11-42 alter the permanent and induced dipoles of the peptide. Specifically, we found that AßpE3-42 and AßpE11-42 have modification-specific backbone and sidechain polarization response and perturbed solvation properties that shift the Aß conformational ensemble.

Functional analysis of adipokinetic hormone signaling in reproductive diapause of Coccinella septempunctata.

BACKGROUND: The ladybeetle, Coccinella septempunctata, an important predator, is widely used to control aphids, whiteflies, mites, thrips, and lepidopteran pests. Diapause control technology is key to extending C. septempunctata shelf-life and commercialization. Lipid accumulation is a major feature of reproductive diapause, but the function of AKH signaling as a regulator of lipid mobilization in reproductive diapause remains unclear. This study aimed to identify and characterize AKH and AKHR genes, and clarify their functions in reproductive diapause. RESULTS: The relative expression levels of CsAKH and CsAKHR were the highest in the head and fat body, respectively, and were significantly decreased under diapause conditions, both in developmental stages and tissues (head, midgut, fat body, and ovary). Furthermore, CsAKH and CsAKHR expression was increased significantly after juvenile hormone (JH) injection, but CsMet silencing significantly inhibited CsAKH and CsAKHR expression, whereas CsMet knockdown blocked the induction effect of JH. CsAKH and CsAKHR knockdown significantly reduced water content, increased lipid storage, and promoted the expression of genes related to lipid synthesis, but significantly blocked ovarian development, and induced forkhead box O (FOXO) gene expression in C. septempunctata under reproduction conditions. By contrast, injection of AKH peptide significantly inhibited FOXO expression, reduced lipid storage, and increased water content in C. septempunctata under diapause conditions. CONCLUSION: These results indicate that CsAKH and CsAKHR are involved in the regulation of lipid accumulation and ovarian development during diapause in C. septempunctata, and provide a promising target for manipulating C. septempunctata diapause. © 2024 Society of Chemical Industry.

Ophthalmic acid is a glutathione regulating tripeptide.

Since its discovery in 1958 in the lens of cows, ophthalmic acid (OPH) has stood in the shadow of its anti-oxidant analog: glutathione (GSH). Lacking the thiol group that gives GSH many of its important properties, ophthalmic acid's function has remained elusive, and it has been widely presumed to be an accidental product of the same enzymes. In this review, we compile evidence demonstrating that OPH is a ubiquitous metabolite found in bacteria, plants, fungi, and animals, produced through several layers of metabolic regulation. We discuss the limitations of the oft-repeated suggestions that aberrations in OPH levels should solely indicate GSH deficiency or oxidative stress. Finally, we discuss the available literature and suggest OPH's role in metabolism as a GSH-regulating tripeptide; controlling both cellular and organelle influx and efflux of GSH, as well as modulating GSH-dependent reactions and signaling. Ultimately, we hope that this review reinvigorates and directs more research into this versatile metabolite.

Authentication of a lophotrochozoan adipokinetic hormone receptor in a Gastropod, Aplysia californica.

Gonadotropin-releasing hormone (GnRH) superfamily comprises multiple families of signaling peptides in both protostomes and deuterostomes. Among this superfamily, vertebrate GnRH stimulates reproduction, but other GnRH superfamily members elicit diverse pleiotropic effects. Within the GnRH superfamily members, adipokinetic hormone (AKH) and its receptor are well described in ecdysozoans but understudied in other lineages. To fill this knowledge gap, we deorphanized a putative receptor for a lophotrochozoan AKH in a gastropod mollusk, Aplysia californica, and named it Aplca-AKHR. Phylogenetic analysis revealed an orthologous relationship of Aplca-AKHR with ecdysozoan AKHRs and other putative lophotrochozoan AKHRs. Aplca-AKHR bound specifically to the previously identified Aplca-AKH with high affinity and activated the inositol phosphate pathway. Aplca-AKHR was expressed widely among central and peripheral tissues, but most prominently in several central ganglia and the heart. The expression of Aplca-AKHR was downregulated by a hyposaline challenge, consistent with a role in volume and fluid regulation previously described for its ligand, Aplca-AKH. In summary, this is the first pairing of a lophotrochozoan AKH with its cognate receptor. Expression data further support diverse central and peripheral roles, including volume and fluid control, of this ligand/receptor pair.

The Bacteroidetes Q-rule and glutaminyl cyclase activity increase the stability of extracytoplasmic proteins.

IMPORTANCE: Exclusively in the Bacteroidetes phylum, most proteins exported across the inner membrane via the Sec system and released into the periplasm by type I signal peptidase have N-terminal glutamine converted to pyroglutamate. The reaction is catalyzed by the periplasmic enzyme glutaminyl cyclase (QC), which is essential for the growth of Porphyromonas gingivalis and other periodontopathogens. Apparently, pyroglutamyl formation stabilizes extracytoplasmic proteins and/or protects them from proteolytic degradation in the periplasm. Given the role of P. gingivalis as the keystone pathogen in periodontitis, P. gingivalis QC is a promising target for the development of drugs to treat and/or prevent this highly prevalent chronic inflammatory disease leading to tooth loss and associated with severe systemic diseases.

Increased TSPO expression, pyroglutamate-modified amyloid beta (AßN3(pE)) accumulation and transient clustering of microglia in the thalamus of Tg-SwDI mice.

Epidemiological studies showed that Alzheimer's disease (AD) and cerebral amyloid angiopathy (CAA) frequently co-occur; however, the precise mechanism is not well understood. A unique animal model (Tg-SwDI mice) was developed to investigate the early-onset and robust accumulation of both parenchymal and vascular Aß in the brain. Tg-SwDI mice have been extensively used to study the mechanisms of cerebrovascular dysfunction, neuroinflammation, neurodegeneration, and cognitive decline observed in AD/CAA patients and to design biomarkers and therapeutic strategies. In the present study, we documented interesting new features in the thalamus of Tg-SwDI mice: 1) a sharp increase in the expression of ionized calcium-binding adapter molecule 1 (Iba-1) in microglia in 6-month-old animals; 2) microglia clustering at six months that disappeared in old animals; 3) N-truncated/modified AßN3(pE) peptide in 9-month-old female and 12-month-old male mice; 4) an age-dependent increase in translocator protein (TSPO) expression. These findings reinforce the versatility of this model for studying multiple pathological issues involved in AD and CAA.

The proline effect and the tryptophan immonium ion assist in de novo sequencing of adipokinetic hormones.

Adipokinetic hormones (AKHs) in Arthopoda are characterized by special sequence features including limited choices of amino acid residues in certain positions, such as Trp in position 8. Over 100 different AKHs have been described, but de novo sequencing of novel peptide hormones can be a challenge. In a project of analyzing corpora cardiaca extracts from two fly species, two different moths, a termite and a beetle for their AKHs, we noted specific patterns in the fragmentation spectra of octapeptides in electrospray Q-TOF experiments resulting from the presence of Pro in position 6. The preference for cleavage N-terminal to Pro residues created an abundant y3″-ion, which, in conjunction with the two b-ions resulting from the fragmentation before and after Pro, provided a marker pattern. As Pro6 occurs in about 61% of known AKHs, this information is highly relevant for sequence elucidation. Moreover, the default presence of Trp8 allowed the use of its immonium ion for AKH candidate identification. In addition, we assembled the known AKH sequences from the literature and sequences of AKH-type format found in the Uniprot database in a single online resource. These efforts assisted in the analysis workflow and led to the assignment of two novel AKHs and evidence for the presence of Melme-CC and Dorpa-AKH in the corpus cardiacum of the scarab beetle Sinodendron cylindricum.

Comparative analysis of adipokinetic hormones and their receptors in Blattodea reveals novel patterns of gene evolution.

Adipokinetic hormone (AKH) is a neuropeptide produced in the insect corpora cardiaca that plays an essential role in mobilising carbohydrates and lipids from the fat body to the haemolymph. AKH acts by binding to a rhodopsin-like G protein-coupled receptor (GPCR), the adipokinetic hormone receptor (AKHR). In this study, we tackle AKH ligand and receptor gene evolution as well as the evolutionary origins of AKH gene paralogues from the order Blattodea (termites and cockroaches). Phylogenetic analyses of AKH precursor sequences point to an ancient AKH gene duplication event in the common ancestor of Blaberoidea, yielding a new group of putative decapeptides. In total, 16 different AKH peptides from 90 species were obtained. Two octapeptides and seven putatively novel decapeptides are predicted for the first time. AKH receptor sequences from 18 species, spanning solitary cockroaches and subsocial wood roaches as well as lower and higher termites, were subsequently acquired using classical molecular methods and in silico approaches employing transcriptomic data. Aligned AKHR open reading frames revealed 7 highly conserved transmembrane regions, a typical arrangement for GPCRs. Phylogenetic analyses based on AKHR sequences support accepted relationships among termite, subsocial (Cryptocercus spp.) and solitary cockroach lineages to a large extent, while putative post-translational modification sites do not greatly differ between solitary and subsocial roaches and social termites. Our study provides important information not only for AKH and AKHR functional research but also for further analyses interested in their development as potential candidates for biorational pest control agents against invasive termites and cockroaches.

Physiological responses to honeybee venom poisoning in a model organism, the firebug Pyrrhocoris apterus.

In this study, the biochemical and physiological features of the firebug Pyrrhocoris apterus were investigated to understand the impact of the honeybee Apis mellifera venom on them using physiological methods (mortality, total level of metabolism), biochemical methods (ELISA, mass spectrometry, polyacrylamide gel electrophoresis, spectrophotometry) and molecular methods (real-time PCR). Together, the obtained findings suggest that venom injection increased the level of adipokinetic hormone (AKH) in the CNS of P. apterus, indicating that this hormone plays a key role in activating defence responses. Furthermore, histamine levels in the gut increased significantly after envenomation and did not seem to be modulated by AKH. In contrast, histamine levels in the haemolymph increased after treatment with AKH and AKH + venom. In addition, we found that vitellogenin levels in haemolymph decreased in both males and females after venom application. Lipids, which are the main energy metabolites used by Pyrrhocoris, were significantly exhausted from the haemolymph after the administration of venom and the co-application with AKH reversed this effect. However, we did not find much influence on the effect of digestive enzymes after the injection of venom. Our research has highlighted the noticeable effect of bee venom on P. apterus' body and provided new insights into the role of AKH in controlling defensive responses. However, it is also likely that there will be alternative defence mechanisms.

Solid-phase synthesis and pathological evaluation of pyroglutamate amyloid-ß3-42 peptide.

Pyroglutamate amyloid-ß3-42 (AßpE3-42) is an N-terminally truncated and pyroglutamate-modified Aß peptide retaining highly hydrophobic, amyloidogenic, and neurotoxic properties. In Alzheimer's disease (AD) patients, AßpE3-42 peptides accumulate into oligomers and induce cellular toxicity and synaptic dysfunction. AßpE3-42 aggregates further seed the formation of amyloid plaques, which are the pathological hallmarks of AD. Given that AßpE3-42 peptides play critical roles in the development of neurodegeneration, a reliable and reproducible synthetic access to these peptides may support pathological and medicinal studies of AD. Here, we synthesized AßpE3-42 peptides through the microwave-assisted solid-phase peptide synthesis (SPPS). Utilizing thioflavin T fluorescence assay and dot blotting analysis with anti-amyloid oligomer antibody, the amyloidogenic activity of synthesized AßpE3-42 peptides was confirmed. We further observed the cytotoxicity of AßpE3-42 aggregates in cell viability test. To examine the cognitive deficits induced by synthetic AßpE3-42 peptides, AßpE3-42 oligomers were intracerebroventricularly injected into imprinting control region mice and Y-maze and Morris water maze tests were performed. We found that AßpE3-42 aggregates altered the expression level of postsynaptic density protein 95 in cortical lysates. Collectively, we produced AßpE3-42 peptides in the microwave-assisted SPPS and evaluated the amyloidogenic and pathological function of the synthesized peptides.

Molecular Mechanism of L-Pyroglutamic Acid Interaction with the Human Sour Receptor.

Taste is classified into five types, each of which has evolved to play its respective role in mammalian survival. Sour taste is one of the important ways to judge whether food has gone bad, and the sour taste receptor (PKD2L1) is the gene behind it. Here, we investigated whether L-pyroglutamic acid interacts with sour taste receptors through electrophysiology and mutation experiments using Xenopus oocytes. R299 of hPKD2L1 was revealed to be involved in L-pyroglutamic acid binding in a concentration-dependent manner. As a result, it is possible to objectify the change in signal intensity according to the concentration of L-pyroglutamic acid, an active ingredient involved in the taste of kimchi, at the molecular level. Since the taste of other ingredients can also be measured with the method used in this experiment, it is expected that an objective database of taste can be created.

Functional insight and cell-specific expression of the adipokinetic hormone/corazonin-related peptide in the human disease vector mosquito, Aedes aegypti.

The adipokinetic hormone/corazonin-related peptide (ACP) is an insect neuropeptide structurally intermediate between corazonin (CRZ) and adipokinetic hormone (AKH). Unlike the AKH and CRZ signaling systems that are widely known for their roles in the mobilization of energy substrates and stress responses, respectively, the main role of ACP and its receptor (ACPR) remains unclear in most arthropods. The current study aimed to localize the distribution of ACP in the nervous system and provide insight into its physiological roles in the disease vector mosquito, Aedes aegypti. Immunohistochemical analysis and fluorescence in situ hybridization localized the ACP peptide and transcript within a number of cells in the central nervous system, including two pairs of laterally positioned neurons in the protocerebrum of the brain and a few ventrally localized neurons within the pro- and mesothoracic regions of the fused thoracic ganglia. Further, extensive ACP-immunoreactive axonal projections with prominent blebs and varicosities were observed traversing the abdominal ganglia. Given the prominent enrichment of ACPR expression within the abdominal ganglia of adult A. aegypti mosquitoes as determined previously, the current results indicate that ACP may function as a neurotransmitter and/or neuromodulator facilitating communication between the brain and posterior regions of the nervous system. In an effort to elucidate a functional role for ACP signaling, biochemical measurement of energy substrates in female mosquitoes revealed a reduction in abdominal fat body in response to ACP that matched the actions of AKH, but interestingly, a corresponding hypertrehalosaemic effect was only found in response to AKH since ACP did not influence circulating carbohydrate levels. Comparatively, both ACP and AKH led to a significant increase in haemolymph carbohydrate levels in male mosquitoes while both peptides had no influence on their glycogen stores. Neither ACP nor AKH influenced circulating or stored lipid levels in both male and female mosquitoes. Collectively, these results reveal ACP signaling in mosquitoes may have complex sex-specific actions, and future research should aim to expand knowledge on the role of this understudied neuropeptide.

Role of pyroglutamic acid in cumulus cells of women with polycystic ovary syndrome.

PURPOSE: Polycystic ovary syndrome is a complex heterogeneous endocrine disorder associated with established metabolic abnormalities and is a common cause of infertility in females. Glutathione metabolism in the cumulus cells (CCs) of women with PCOS may be correlated to the quality of oocytes for infertility treatment; therefore, we used a metabolomics approach to examine changes in CCs from women with PCOS and oocyte quality. METHODS: Among 135 women undergoing fertility treatment in the present study, there were 43 women with PCOS and 92 without. CCs were collected from the two groups and levels of pyroglutamic acid were measured using LC-MS/MS followed by qPCR and Western blot analysis to examine genes and proteins involved in pyroglutamic acid metabolism related to glutathione synthesis. RESULTS: Women with PCOS showed increased levels of L-pyroglutamic acid, L-glutamate, and L-phenylalanine and decreased levels of Cys-Gly and N-acetyl-L-methionine. Gene expression of OPLAH, involved in pyroglutamic synthesis, was significantly increased in women with PCOS compared with those without. Gene expression of GSS was significantly decreased in women with PCOS and synthesis of glutathione synthetase protein was decreased. Expression of nuclear factor erythroid 2-related factor 2, involved in resistance to oxidative stress, was significantly increased in women with PCOS. CONCLUSIONS: CCs of women with PCOS showed high concentrations of pyroglutamic acid and reduced glutathione synthesis, which causes oxidative stress in CCs, suggesting that decreased glutathione synthesis due to high levels of pyroglutamic acid in CCs may be related to the quality of oocytes in women with PCOS.