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Edible insects are a promising source of bioactive compounds with diverse health benefits. This study investigated the immunomodulatory properties of polysaccharides isolated from Protaetia brevitarsis seulensis larvae (PBSL). Polysaccharides were fractionated using a molecular weight cutoff membrane, and among these fractions, the higher molecular weight fraction (H-PBSL, 666.84 kDa) demonstrated significant immunomodulatory activity. Methylation and NMR structural analyses revealed H-PBSL to be an acidic heteroglycan with a complex structure, consisting of a backbone of repeating (1→4)-linked α-glucan units highly branched at O-6 positions with T-α-Glcp, T-α-GlcpA, and T-β-Galp. The immunomodulatory effects of H-PBSL were evaluated using RAW264.7 macrophage cells. H-PBSL treatment enhanced phagocytic activity and increased the expression of immune modulators and macrophage activation surface molecules. In addition, H-PBSL activated the NF-κB signaling pathway, evidenced by increased phosphorylation of IκB and NF-κB, and translocation of NF-κB from cytosol to nucleus. Moreover, inhibition of Toll-like receptor 4 (TLR4) reduced H-PBSL-induced nitric oxide synthesis, indicating TLR4′s pivotal role in H-PBSL-mediated macrophage activation. These findings highlight the potential of H-PBSL as a novel immunomodulatory agent derived from an edible insect, with possible applications in functional foods and nutraceuticals.

Modulation of osteoclast formation could be a therapeutic target for inhibiting pathological bone destruction. The receptor activator of nuclear factor (NF)-κB ligand (RANKL) is known to be an essential factor in osteoclast differentiation and activation inducers. However, whether Protaetia brevitarsis seulensis (P. brevitarsis) larvae—a traditional animal-derived medicine used in many Asian countries—can inhibit RANKL-induced osteoclast formation and prevent ovariectomy (OVX)-induced bone loss has not been evaluated. Here, we aimed to investigate the anti-osteoporotic effects of P. brevitarsis larvae ethanol extract (PBE) in RANKL-stimulated RAW264.7 cells and OVX mice. In vitro, PBE (0.1, 0.5, 1, and 2 mg/mL) decreased RANKL‑induced tartrate-resistant acid phosphatase (TRAP) activity and expression of osteoclastogenesis-associated genes and proteins. Furthermore, PBE (0.1, 0.5, 1, and 2 mg/mL) significantly inhibited the phosphorylation of p38 and NF-κB. Female C3H/HeN mice were divided into five groups (n = 5 per group), namely, sham-operated, OVX, OVX+PBEL (100 mg/kg, oral gavage), OVX+PBEH (200 mg/kg, oral gavage), and OVX+estradiol (0.03 μg/day, subcutaneous injection). High doses of PBE significantly increased femoral bone mineral density (BMD) and bone volume/tissue volume (BV/TV), whereas femoral bone surface/bone volume (BS/BV) and osteoclastogenesis-associated protein expression decreased compared to those in the OVX group. Moreover, PBE (200 mg/kg) significantly increased estradiol and procollagen type I N-terminal propeptide and decreased N-terminal telopeptide of type I collagen and C-terminal telopeptide of type I collagen compared to those in the OVX group. Our results suggest that PBE can be an effective therapeutic candidate for preventing or treating postmenopausal osteoporosis.

A white-spotted flower chafer Protaetia brevitarsis seulensis widely distributed in Asian countries is traditionally used in oriental medicine. This study explored gene expression abundance with respect to wing development and metamorphosis in P. b. seulensis based on the large-scale RNA-seq data. The transcriptome assembly consists of 23,551 high-quality transcripts which are approximately 96.7% covered. We found 265 wing development genes, 19 metamorphosis genes, and 1,314 candidates. Of the 1,598 genes, 1,594 are included exclusively in cluster 4 with similar gene co-expression patterns. The network centrality analyses showed that wing development- and metamorphosis-related genes have a high degree of betweenness centrality and are expressed most highly in eggs, moderately in pupa and adults, and lowest in larva. This study provides some meaningful clues for elucidating the genetic modulation mechanism of wing development and metamorphosis in P. b. seulensis.

Abstract Malignant melanoma is highly resistant to conventional treatments and is one of the most aggressive types of skin cancers. Conventional cancer treatments are limited due to drug resistance, tumor selectivity, and solubility. Therefore, new treatments with fewer side effects and excellent effects should be developed. In previous studies, we have analyzed antimicrobial peptides (AMPs), which showed antibacterial and anti-inflammatory effects in insects, and some AMPs also exhibited anticancer efficacy. Anticancer peptides (ACPs) are known to have fewer side effects and high anticancer efficacy. In this study, the insect-derived peptide poecilocorisin-1 (PCC-1) did not induce toxicity in the human epithelial cell line HaCaT, but its potential as an anticancer agent was confirmed through specific effects of antiproliferation, apoptosis, and cell cycle arrest in two melanoma cell lines, SK-MEL-28 and G361. Additionally, we discovered a novel anticancer mechanism of insect-derived peptides in melanoma through the regulation of transcription factor Sp1 protein, which is overexpressed in cancer, apoptosis, and cell cycle-related proteins. Taken together, this study aims to clarify the anticancer efficacy and safety of insect-derived peptides and to present their potential as future therapeutic agents.

Abstract Background Field cricket (Gryllus bimaculatus) is newly emerged as an edible insect in several countries. Anti-inflammatory effect of glycosaminoglycan derived from this cricket on chronic disease animal model such as diabetic mouse has not been fully investigated yet. Thus, the objective of this study was to determine the anti-oxidative effect of such glycosaminoglycan on diabetic mouse. Methods To discover potential therapeutic agents, field cricket glycosaminoglycan (GbG) was tested in the present study. Its anti-oxidative activities in diabetic mice were determined based on its abilities to reduce glucose, ALT, AST, ALP, LDL-cholesterol and BUN levels. Dung beetle (C. molossus) glycosaminoglycan (CaG) was used as a positive control. Db mice were intraperitoneally administered for 1 month according to their group assignments: 1) normal (DB-Hetero); 2) control (DB-Homo); 3) 5 mg/kg treatment of CaG (CaG5); 4) 5 mg/kg treatment of GbG (GbG5); and 5) 10 mg/kg treatment of metformin (Metformin 10). Results Blood glucose level decreased after 1st week of treatment with GbG. LDL-cholesterol and alkaline phosphatase levels were also inhibited by GbG. Markers of oxidative damage, such as protein carbonyl content and levels of hepatocellular biomarkers, were reduced in db mice treated with GbG. Especially anti-oxidative activities of catalase, superoxide dismutase and glutathione peroxidase were significantly increased in GbG treated group compared to those in the control (Db Homo). GbG was composed of heparin disaccharides. Its main N-glycan was identified as Hex9GlcNAc2 (m/z 1905.7) with neutral mono-sugar mainly comprising of hexose and L (+) rhamnose by mass spectroscopy. Conclusions Sero-biochemical and hepatocellular anti-oxidant assay results in db mice suggest that cricket (G. bimaculatus) glycosaminoglycan might possess anti-oxidative effect in diabetic state.

Probiotic Gluconacetobacter strains are intestinal microbes with beneficial effects on human health. Recently, researchers have used these strains to biosynthesize metal and non-metal nanoparticles for treating various chronic diseases. Despite their importance in nanotechnology, gold nanoparticles (AuNPs) biosynthesized by Gluconacetobacter species have not been clearly identified for treating inflammation and inflammation-associated diseases. While ginsenoside CK has strong pharmaceutical activity, it also has strong cytotoxicity and hydrophobicity which is hurdle to make formulation. Peptide–nanoparticle hybrids are gaining increasing attention for their potential biomedical applications, including human inflammatory diseases. Herein, we developed peptide CopA3 surface conjugated and ginsenoside compound K (CK) loaded gold nanoparticles (GNP-CK-CopA3), which intracellularly synthesised by the probiotic Gluconacetobacter liquefaciens kh-1, to target lipopolysaccharide (LPS)-activated RAW264.7 macrophages. The synthetic GNP-CK-CopA3 was characterised by various instrumental techniques. The results of our cellular uptake and MTT assays exhibited obvious drug intracellular delivery without significant cytotoxicity. In addition, pre-treatment with GNP-CK-CopA3 significantly ameliorated LPS-induced nitric oxide (NO) and reactive oxygen species (ROS) production and suppressed the mRNA and protein expression of pro-inflammatory cytokines in macrophages. Furthermore, GNP-CK-CopA3 efficiently inhibited the activation of the nuclear factor-κB (NF-κB) and mitogen-activating protein kinase (MAPK) signalling pathways. Taken together, our findings highlight the potential of using peptide–nanoparticle hybrids in the development of anti-inflammatory approaches and providing the experimental foundation for further application.

Abstract Background Dung beetle glycosaminoglycan is known to possess anti-aging activities. However, its anti-cancer mechanisms are not fully elucidated yet. The objective of this study was to evaluate the anti-cancer effect of insect-derived polymer dung beetle glycosaminoglycan (GAG) after intraperitoneally injecting it to melanoma mice induced by B16F10 cells. Methods To determine molecular mechanism involved in the anti-cancer effect of dung beetle GAG, its origin N-glycan under 3KD Dalton was assayed for melanoma cell cytotoxicity. Quantitative comparisons of adhesive molecule on extracellular matrix and activities of tissue inhibitor of metalloprotease 2 (TIMP-2) were also investigated. In vivo anti-cancer effect of dung beetle GAG on solid tumor size, survival time and gene-expression profiles was also assayed using B10F10 melanoma mice model. Mice with induced melanoma were then treated with Catharsius molossus (dung beetle) GAG (CaG) at 5 mg/kg for 8 weeks to investigate its anti-cancer effects compared to bumblebee (Bombus ignitus) queen glycosaminoglycan (IQG) and Huechys sanguinea glycosaminoglycan (HEG). Results These N-glycans derived from these GAG were composed of many linear heparinoid polysaccharides, polymers with hexose and N-acetylhexose. Adminstration with these GAGs increased survival time and decreased melanoma sizes in mice, in accordance with their inhibitory effects on cell growth ratio of melanoma B16F10. In addition, treatment with N-glycans derived from theses glycosaminoglycan increased activities of TIMP-2 in HMVEC cells pretreated with TNF-alpha and in melanoma cells, suggesting that they had anti-inflammatory and anticancer activities. In DNA microarray results, compared to control, CaG treated mouse group showed upregulation of 192 genes including collagen,typeI,alpha1 (Col1a1), consistent with the highly increased in vitro extracellular matrix (ECM) adhesion on collagen 1 and up-regulation of heparanase (Hpse). After treatment with CaG, a total of 152 genes were down-regulated, including nuclear RNA export factor (Nxf3) and hyaluronan proteoglycan link protein1 (Hapln1). Conclusions Glycosaminoglycan, CaG can strengthen ECM by increasing activity of TIMP-2 and adhesion activity on collagen known to inhibit changes of ECM, leading to tumor cell invasion and progression.

White-spotted flower chafer (Protaetia brevitarsis) is an edible insect and its larva was used as a traditional Asian medicine. It’s a promising material as a novel food source because of its nutritional components. In this study, as part of the preclinical toxicity program, we evaluated the toxicity of freeze-dried P. brevitarsis larva powder to develop a novel food material. In a single-dose oral toxicity study in rats, there were no changes in mortality, clinical observations, and body weight in rats administered 5000 mg/kg P. brevitarsis larva powder. In a 13-week oral repeated dose toxicity study in rats, there were no adverse effects or changes in mortality, clinical observations, body weight, food consumption, ophthalmology, clinical pathology, necropsy, organ weight, and histopathology at doses of 300, 1000, and 3000 mg/kg/day. In identification of allergic reactions, P. brevitarsis larva powder induced no increases of serum immunoglobulin E and histamine concentrations over 13 weeks of oral administration in rats. In a genotoxicity assessment, P. brevitarsis larva powder didn’t provoke bacterial reverse mutations, chromosomal aberrations, and micronucleated reticulocytes. Therefore, freeze-dried P. brevitarsis larva powder shows no evidence of toxic and mutagenic changes under the experimental conditions of the present in vitro and in vivo studies. Keywords: Protaetia brevitarsis larva, Edible insect, Single-dose oral toxicity, 13-week oral toxicity, Genotoxicity

Abstract The edible grasshopper Oxya chinensis sinuosa is consumed worldwide for its various medicinal effects. The purpose of this study was to investigate potential bioactive antithrombotic and antiplatelet compounds from O. chinensis sinuosa. Five N-acetyldopamine dimers (1–5) were isolated from O. chinensis sinuosa and compounds 1 and 2 were identified as new chemicals with chiral centers at H-2 and H-3 of the benzo-1,4-dioxane structure. Compounds 1–4 were found to have both FXa and platelet aggregation inhibitory activities. These compounds inhibited the catalytic activity of FXa toward its synthetic substrate, S-2222, by noncompetitive inhibition, and inhibited platelet aggregation induced by ADP and U46619. Furthermore, compounds 1–4 showed enhanced antithrombotic effects, which were assessed using in vivo models of pulmonary embolism and arterial thrombosis. The isolated compounds also showed anticoagulant effects in mice. However, compounds 1–4 did not prolong bleeding time in mice, as shown by tail clipping. N-Acetyldopamine dimers, including two new stereoisomers 1 and 2, are novel antithrombotic compounds showing both FXa inhibition and antiplatelet aggregation activity with a low bleeding risk. Collectively, these results suggest that compounds 1–4 could serve as candidates and provide scaffolds for development of new antithrombotic drugs.

Abstract Background This study aimed to evaluate the anti-aging effect of a newly prepared insect-derived compound, dung beetle glycosaminoglycan (GAG), given intraperitoneally to old SD rats as part of their diet for 1 month. Insect GAG administration was found to be related to a reduction in oxidative damage, hepato-cellular biomarker levels, protein carbonyl content, and malondialdehyde concentration. The anti-aging-related molecular genetic mechanisms of dung beetle GAG are not yet fully elucidated. Results Catharsius molossus (a type of dung beetle) GAG (CaG) possessed anti-aging activities; it reduced the serum level of creatinine kinase, had aortic vasorelaxant activities and cardioprotective actions, and maintained a normal glucose level in treated rats. Microarray analysis was performed with a rat 30 K cDNA clone set array to identify the gene-expression profiles of 14-month-old SD rats treated with dung beetle glycosaminoglycan 5 mg/kg (CaG5) over a 1-month period, which was done to investigate its anti-aging effect as compared to that of either Bombus ignitus (a type of bumblebee) queen GAG 5 mg/kg (IQG5) or chondroitin sulfate 10 mg/kg. CaG5 and IQG5 had marked anti-inflammatory effects, bringing about inhibition of free fatty acid, uric acid, sGPT, IL-1 beta, and CK values. In addition, anticoagulant and antithrombotic effects were seen: the concentration of factor 1 (fibrinogen) was increased in CaG- treated rat plasma. The CaG5-treated rat group, compared to the control, displayed upregulation of 131 genes, including lipocalin 2 (Lbp) and a serine peptidase inhibitor, Kaszal type3 (Spink3), and 64 downregulated genes, including lysyl oxidase (Lox), serine dehydratase (sds), and retinol saturase (Retsat). Conclusion Our data suggest that dung beetle glycosaminoglycan may be a helpful treatment for aged rats, which indicates its potential as a therapeutic biomaterial for aging.

An insect’s innate immune system is the front line of defense against many invading microorganisms. One of the important components of this defense system is antimicrobial peptides (AMPs). Papiliocin is a well-studied antimicrobial peptide (AMP) isolated from the swallowtail butterfly, Papilio xuthus, and it was previously reported to be effective against Gram-positive bacteria, Gram-negative bacteria, and fungi, particularly in drug resistant Gram-negative bacteria. Hence, we aimed to identify novel AMPs from Papilio xuthus using its transcriptome. We immunized the swallowtail butterfly with Escherichia coli, Staphylococcus aureus, Candida albicans, and the total RNA was isolated. De novo transcriptome assembly and functional annotations were conducted, and AMPs were predicted using an in-silico pipeline. The obtained 344,804,442 raw reads were then pre-processed to retrieve 312,509,806 (90.6%) total clean reads. A total of 38,272 unigenes were assembled with the average length of 1010 bp. Differential gene expression analysis identified 584 and 1409 upregulated and downregulated genes, respectively. The physicochemical, aggregation, and allergen propensity were used as filtration criteria. A total of 248 peptides were predicted using our in-house pipeline and the known AMPs were removed, resulting in 193 novel peptides. Finally, seven peptides were tested in vitro and three peptides (Px 5, 6, and 7) showed stronger antimicrobial activity against Gram-negative bacteria and yeast. All the tested peptides were non-allergens. The identified novel AMPs may serve as potential candidates for future antimicrobial studies.

Antimicrobial peptides (AMPs) are the frontline innate defense system evolutionarily preserved in insects to combat invading pathogens. These AMPs could serve as an alternative to classical antibiotics to overcome the burden of treating multidrug resistant bacteria. Psacotheasin, a knottin type AMP was isolated from Psacothea hilaris and shown to exhibit antimicrobial activity, especially against fungi through apoptosis mediated cell death. In this study, we aimed to identify novel probable AMPs from Psacothea hilaris, the yellow spotted longicorn beetle. The beetle was immunized with the two bacterial strains (E. coli and S. aureus), and the yeast strain C. albicans. After immunization, total RNA was isolated and sequenced in Illumina platform. Then, beetle transcriptome was de novo assembled and searched for putative AMPs with the known physiochemical features of the AMPs. A selection of AMP candidates were synthesized and tested for antimicrobial activity. Four peptides showed stronger activity against E. coli than the control AMP, melittin while one peptide showed similar activity against S. aureus. Moreover, four peptides and two peptides showed antifungal activity stronger than and similar to melittin, respectively. Collectively one peptide showed both antibacterial and antifungal activity superior to melittin; thus, it provides a potent antimicrobial peptide. All the peptides showed no hemolysis in all the tested concentrations. These results suggest that in silico mining of insects’ transcriptome could be a promising tool to obtain and optimize novel AMPs for human needs.

The larva of Allomyrina dichotoma (family Scarabaeidae) is an edible insect that is registered in the Korean Food Standards Codex as a food resource. The chemical study on the larvae of A. dichotoma resulted in the isolation of three new tetrahydroquinolines, allomyrinaines A–C (1–3), one new dopamine derivative, allomyrinamide A (4), and four known compounds (5–8). The structures were elucidated on the basis of 1D and 2D nuclear magnetic resonance (NMR) and MS spectroscopic data analysis. Allomyrinaines A–C (1–3) possessed three stereogenic centers at C-2, C-3, and C-4, whose relative configurations were determined by analyses of the coupling constants and the nuclear Overhauser enhancement spectroscopy (NOESY) data, as well as DP4+ calculation. The anti-inflammatory effects of compounds 1–4 were evaluated in human endothelial cells. Allomyrinaines A–C (1–3) could stabilize vascular barrier integrity on lipopolysaccharide (LPS)-induced vascular inflammation via inhibition of the nuclear factor-κB (NF-κB) pathway. The physiologically relevant concentration was confirmed by Q-TOF-MS-based quantitative analysis on allomyrinaines A–C in crude extract. This study suggests that allomyrinaines A–C (1–3) are bioactive constituents of A. dichotoma to treat vascular inflammatory disorder.

Beta-amyloid peptide (Aβ) damage is one of major potential causes of Alzheimer's disease (AD) and its modulation has emerged as a promising approach to control the onset of AD. In the present study, the effects of oleic acid (OA) against Aβ25–35-stimulated neurotoxicity, inflammatory responses, and further molecular mechanism underlying the neuroprotective properties of OA in PC12 cells were investigated. Pre-treatment of OA significantly decreased Aβ25–35-mediated cytotoxicity by increasing cell viability through the attenuation of intracellular reactive oxygen species (ROS) level and downregulation of pro-apoptotic activated caspase-3, thereby mitigating apoptotic morphological alterations. Improper up-regulation of both cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) by Aβ25–35 was significantly suppressed by preconditioning of OA through repression of the inhibitory unit I-κB degradation, which impedes subsequent nuclear translocation of the functionally active subunit of transcription factor nuclear factor-kappa B (NF-κB). OA noticeably attenuated Aβ25–35-stimulated phosphorylation of p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK1/2), and c-Jun-N-terminal kinase (JNK). Taken together, these findings suggest that the mechanisms responsible for anti-apoptotic and anti-inflammatory properties of OA in Aβ25–35-mediated neuronal damage is associated with COX-2 and iNOS downregulation through activation of NF-κB mediated by upstream kinases including JNK, ERK and p38 MAPK.

To clarify the anti-obesity effect of Allomyrina dichotoma larvae (ADL), we previously reported that ADL block adipocyte differentiation on 3T3-L1 cell lines through downregulation of transcription factors, such as peroxisome proliferator-activated receptor-γ (PPARG) and CCAAT/enhancer binding protein-α (CEBPA). In this study, we tested whether ADL prevent obesity in mice fed a high-fat diet (HFD) and further investigated the mechanism underlying the effects of ADL. All mice were maintained on a normal-fat diet (NFD) for 1 week and then assigned to one of five treatment groups: (1) NFD; (2) HFD; (3) HFD and 100 mg·kg−1·day−1 ADL; (4) HFD and 3000 mg·kg−1·day−1ADL; or (5) HFD and 3000 mg·kg−1·day−1 yerba mate (Ilex paraguariensis, positive control). ADL and yerba mate were administered orally daily. Mice were fed experimental diets and body weight was monitored weekly for 6 weeks. Our results indicated that ADL reduced body weight gain, organ weight and adipose tissue volume in a dose-dependent manner. Body weight gain was approximately 22.4% lower compared to mice fed only HFD, but the difference did not reach the level of statistical significance. Real-time polymerase chain reaction (PCR) analysis revealed that gene expression levels of PPARG, CEBPA and lipoprotein lipase (LPL) in the epididymal fat tissue of HFD-fed mice receiving 3000 mg·kg−1·day−1 ADL were reduced by 12.4-, 25.7-, and 12.3-fold, respectively, compared to mice fed HFD only. Moreover, mice administered ADL had lower serum levels of triglycerides and leptin than HFD-fed mice that did not receive ADL. Taken together our results suggest that ADL and its constituent bioactive compounds hold potential for the treatment and prevention of obesity.

Copepods, small aquatic crustaceans, are the most abundant metazoan zooplankton and outnumber every other group of multicellular animals on earth. In spite of ecological and biological importance in aquatic environment, their morphological plasticity, originated from their various lifestyles and their incomparable capacity to adapt to a variety of environments, has made the identification of species challenging, even for expert taxonomists. Molecular approaches to species identification have allowed rapid detection, discrimination, and identification of cryptic or sibling species based on DNA sequence data. We examined sequence variation of a partial mitochondrial cytochrome C oxidase I gene (COI) from 133 copepod individuals collected from the Korean Peninsula, in order to identify and discriminate 94 copepod species covering six copepod orders of Calanoida, Cyclopoida, Harpacticoida, Monstrilloida, Poecilostomatoida and Siphonostomatoida. The results showed that there exists a clear gap with ca. 20 fold difference between the averages of within-specific sequence divergence (2.42%) and that of between-specific sequence divergence (42.79%) in COI, suggesting the plausible utility of this gene in delimitating copepod species. The results showed, with the COI barcoding data among 94 copepod species, that a copepod species could be distinguished from the others very clearly, only with four exceptions as followings: Mesocyclops dissimilis-Mesocyclops pehpeiensis (0.26% K2P distance in percent) and Oithona davisae-Oithona similis (1.1%) in Cyclopoida, Ostrincola japonica-Pseudomyicola spinosus (1.5%) in Poecilostomatoida, and Hatschekia japonica-Caligus quadratus (5.2%) in Siphonostomatoida. Thus, it strongly indicated that COI may be a useful tool in identifying various copepod species and make an initial progress toward the construction of a comprehensive DNA barcode database for copepods inhabiting the Korean Peninsula.

Cockroaches are surrogate hosts for microbes that cause many human diseases. In spite of their generally destructive nature, cockroaches have recently been found to harbor potentially beneficial and medically useful substances such as drugs and allergens. However, genomic information for the American cockroach (Periplaneta americana) is currently unavailable; therefore, transcriptome and gene expression profiling is needed as an important resource to better understand the fundamental biological mechanisms of this species, which would be particularly useful for the selection of novel antimicrobial peptides. Thus, we performed de novo transcriptome analysis of P. americana that were or were not immunized with Escherichia coli. Using an Illumina HiSeq sequencer, we generated a total of 9.5 Gb of sequences, which were assembled into 85,984 contigs and functionally annotated using Basic Local Alignment Search Tool (BLAST), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) database terms. Finally, using an in silico antimicrobial peptide prediction method, 86 antimicrobial peptide candidates were predicted from the transcriptome, and 21 of these peptides were experimentally validated for their antimicrobial activity against yeast and gram positive and -negative bacteria by a radial diffusion assay. Notably, 11 peptides showed strong antimicrobial activities against these organisms and displayed little or no cytotoxic effects in the hemolysis and cell viability assay. This work provides prerequisite baseline data for the identification and development of novel antimicrobial peptides, which is expected to provide a better understanding of the phenomenon of innate immunity in similar species.

Our previous study demonstrated that CopA3, a disulfide dimerof the coprisin peptide analogue (LLCIALRKK), has antibacterialactivity. In this study, we assessed whether CopA3caused cellular toxicity in various mammalian cell lines.CopA3 selectively caused a marked decrease in cell viabilityin Jurkat T, U937, and AML-2 cells (human leukemia cells),but was not cytotoxic to Caki or Hela cells. Fragmentation ofDNA, a marker of apoptosis, was also confirmed in the leukemiacell lines, but not in the other cells. CopA3-induced apoptosisin leukemia cells was mediated by apoptosis inducingfactor (AIF), indicating induction of a caspase-independent signalingpathway. [BMB reports 2012; 45(2): 85-90]

Dot blot hybridization of total RNA from normal and bacteria-injected larvae of the dung beetle Copris tripartitus identified 13 cDNA clones that seem to be associated with the immune response. A cDNA encoding a dung beetle homolog of the heat shock protein HSP70 (CTHSP70) was characterized by full-length sequencing and expression pattern analysis. CTHSP70 was upregulated 4 h after bacterial injection, reached maximum level after 8 h, and declined gradually after 16 h. Our data suggest that CTHSP70 and another 12 genes are involved in the anti-microbial defense that is particularly important for dung beetle larvae living in pathogen-rich conditions.

We sequenced nine introns of 25 silkworm (Bombyx mori L.) strains, assuming that the introns are particularly prone to mutation. Mean sequence divergence and maximum sequence divergence in each intronic sequence among 25 silkworm strains ranged from 0.81% (3.8 nucleotides) ~ 9.15% (85.2 nucleotides) and 1.2% (seven nucleotides) ~ 39.3% (366 nucleotides), respectively. The degree of sequence divergence in some introns is very variable, suggesting the potential of using intronic sequences for strain identification. In particular, some introns were highly promising and convenient strain markers due to the presence of a large indels (e.g., 403 bp and 329 bp) in only a limited number of strains. Phylogenetic analysis using the individual or the nine concatenated intronic sequences showed no clustering on the basis of known strain characteristics. This may further indicate the potential of the intronic sequences for the identification of silkworm strains.

The mechanism of functional insect glycosaminoglycan (GAG) on obesity caused a high fat diet has not yet been elucidated. Therefore, insect glycosaminoglycans derived from Isaria sinclairii, Bombus ignitus (a type of bumblebee) queen, and Gryllus bimaculatus were purified and investigated as a potential functional food. 14-week old male Wistar rats were fed a high-fat diet (HFD) for 6 weeks. There were five groups that received daily intraperitoneal administration of phosphate buffered saline (PBS, control), GbG (GAG from Gryllus bimaculatus) 10 mg/kg, ISG (GAG from Isaria sinclairii) 10 mg/kg, IQG (GAG from Bombus ignites) 10 mg/kg, or Pravastatin (2 mg/kg). All treatments were performed for one month. IQG produced a potential anti-inflammatory effect with the inhibition of c-reactive protein and sero-biochemical parameters of phospholipids and free fatty acids indicative of an anti-hyperlipidemic effect. Abdominal and epididymidal fat weight were reduced in conjunction with a mild increase in body weight. The level of laminin in HMVEC-C cells or fibronectin in HFD rat hepatocytes was significantly affected by these GAG treatments, which regulated adipogenesis and adipocyte function. Compared to the control rats, IQG-treated rats displayed up-regulation of 87 genes (test:control ratio >2.0) including fatty acid synthase and 3-hydroxy-3-methylglutaryl-coenzyme A reductase, with the down-regulation of 47 genes including the uridine diphosphate (UDP) glycosyltransferase 2 families, polypeptidase B, and insulin-like growth factor binding protein 1. The data suggest that IQG could potentially prevent or treat fatty liver or hyperlipidemia.

Despite the increasing interest in insect-based bioactive products, the biological activities of these products are rarely studied adequately. Larvae of Tenebrio molitor, the yellow mealworm, have been eaten as a traditional food and provide many health benefits. Therefore, we hypothesized that T. molitor larvae might influence adipogenesis and obesity-related disorders. In the present study, we investigated the anti-adipogenic and antiobesity effects of T. molitor larvae in vitro and in vivo. The lipid accumulation and triglyceride content in mature adipocytes was reduced significantly (up to 90%) upon exposure to an ethanol extract of T. molitor larvae, without a reduction in cell viability. Exposure also resulted in key adipogenic and lipogenic transcription factors. Additionally, in adipogenic differentiation medium the extract induced phosphorylation of adenosine monophosphate (AMP)-activated protein kinase and mitogen-activated protein kinases. Daily oral administration of T. molitor larvae powder to obese mice fed high-fat diet attenuated body weight gain. We also found that the powder efficiently reduced hepatic steatosis as well as aspartate and alanine transaminase enzyme levels in mice fed a high-fat diet. Our results suggest that T. molitor larvae extract has an antiobesity effect when administered as a food supplement and has potential as a therapeutic agent for obesity.