Tachykinin-related peptides modulate immune-gene expression in the mealworm beetle Tenebrio molitor L.

Tachykinins (TKs) are a group of conserved neuropeptides. In insects, tachykinin-related peptides (TRPs) are important modulators of several functions such as nociception and lipid metabolism. Recently, it has become clear that TRPs also play a role in regulating the insect immune system. Here, we report a transcriptomic analysis of changes in the expression levels of immune-related genes in the storage pest Tenebrio molitor after treatment with Tenmo-TRP-7. We tested two concentrations (10–8 and 10–6 M) at two time points, 6 and 24 h post-injection. We found significant changes in the transcript levels of a wide spectrum of immune-related genes. Some changes were observed 6 h after the injection of Tenmo-TRP-7, especially in relation to its putative anti-apoptotic action. Interestingly, 24 h after the injection of 10–8 M Tenmo-TRP-7, most changes were related to the regulation of the cellular response. Applying 10–6 M Tenmo-TRP-7 resulted in the downregulation of genes associated with humoral responses. Injecting Tenmo-TRP-7 did not affect beetle survival but led to a reduction in haemolymph lysozyme-like antibacterial activity, consistent with the transcriptomic data. The results confirmed the immunomodulatory role of TRP and shed new light on the functional homology between TRPs and TKs

Tachykinin-related peptides modulate immune-gene expression in the mealworm beetle Tenebrio molitor L

The research was partially supported by Grant No. 2021/41/B/NZ9/01054 from the National Science Centre (Poland). AU was supported by a scholarship from the Polish National Agency for Academic Exchange (NAWA) within the Bekker Programme, 2019 (personal stipend, PPN/BEK/2019/1/00167), a scholarship from the Deutscher Akademischer Austauschdienst (DAAD) within the program for Research Stays for University Academics and Scientists, 2018 (personal stipend, 91696887), and a scholarship from the Initiative of Excellence, Research University (ID-UB Project), within the International Junior and Senior Exchange, 2021 (personal stipend, 018/07/POB2/0001). The publication fee was supported by the ID-UB Project (040/08/POB2/0010). JR was funded by DFG FOR 5026.Tachykinins (TKs) are a group of conserved neuropeptides. In insects, tachykinin-related peptides (TRPs) are important modulators of several functions such as nociception and lipid metabolism. Recently, it has become clear that TRPs also play a role in regulating the insect immune system. Here, we report a transcriptomic analysis of changes in the expression levels of immune-related genes in the storage pest Tenebrio molitor after treatment with Tenmo-TRP-7. We tested two concentrations (10-8 and 10-6 M) at two time points, 6 and 24 h post-injection. We found significant changes in the transcript levels of a wide spectrum of immune-related genes. Some changes were observed 6 h after the injection of Tenmo-TRP-7, especially in relation to its putative anti-apoptotic action. Interestingly, 24 h after the injection of 10-8 M Tenmo-TRP-7, most changes were related to the regulation of the cellular response. Applying 10-6 M Tenmo-TRP-7 resulted in the downregulation of genes associated with humoral responses. Injecting Tenmo-TRP-7 did not affect beetle survival but led to a reduction in haemolymph lysozyme-like antibacterial activity, consistent with the transcriptomic data. The results confirmed the immunomodulatory role of TRP and shed new light on the functional homology between TRPs and TKs.Peer reviewe

Effect of Short-Term Desiccation, Recovery Time, and CAPA–PVK Neuropeptide on the Immune System of the Burying Beetle Nicrophorus vespilloides

Environmental conditions, especially related to winter, are crucial for shaping activity of insect immune system. However, our previous research clearly indicates differences in the immune system functioning when the cold stress was induced in the laboratory conditions and when the beetles were collected from natural environment during winter. This is probably related to the multiplication of observed effects by simultaneous presence of different stress factors characteristic of winter, including desiccation. For these reasons, our next step was analysis of the effects of short-term desiccation and recovery time on the functioning of immune system of burying beetle Nicrophorus vespilloides. Also, the effect of Tenmo–PVK-2 (tenebrionid periviscerokinin), member of the CAPA–PVK neuropeptide family, was investigated to better understand observed changes. Short-term desiccation decreases the phagocytic activity of burying beetle haemocytes, which is correlated with a reduction in their adhesive ability. On the other hand, there was a significant increase in phenoloxidase (PO) activity and the level of proPO expression, which may suggest sealing the cuticula by melanin deposition and prevention of water loss. Additionally, the elevated level of defensin expression may be associated with the cross-talk between mechanisms, which participate in insect response to environmental stress, including pathogen infection. After 1 h of recovery time, the activity of tested cellular and humoral mechanisms was mostly back to the control level. However, inhibition of the activity of PO and down-regulation of proPO were noted. These results also indicate importance of melanin deposition during water loss. Moreover, it suggests that some changes in immune system functioning during stress conditions do not have an immune function. Interestingly, part of the effects characteristic of recovery time were also observed after the application of Tenmo–PVK-2, mainly related to haemocyte morphology. These results indicate that CAPA–PVK neuropeptides may also influence on activity of burying beetle immune system. It should be also highlighted that, because of the study of the effects of CAPA–PVK neuropeptides, homologs of vertebrate neuromedin U, the results may be interesting for search evolutionary similarities in the functioning of the neuroendocrine system of insects and vertebrates

Physiological activity of peptides yamamarin and alloferone and their peptidomimetics in Tenebrio molitor L. beetle

Wydział BiologiiW pracy zbadano w układzie heterologicznym z wykorzystaniem chrząszcza T. molitor aktywność immunotropową, gonadotropową oraz embriotoksyczną: alloferonu i jamamarinu oraz ich peptydomimetyków stanowiących koniugaty z nasyconymi kwasami tłuszczowymi: kwasem kaprylowym [C8], mirystynowym [C14] i palmitynowym [C16]. Badania prowadzone na dorosłych chrząszczach wykazały plejotropowe i zróżnicowane oddziaływanie tych związków na procesy związane z funkcjonowaniem układu immunologicznego i rozrodczego oraz rozwój embrionalny. Należy zaznaczyć, że badania z wykorzystaniem testowanych peptydomimetyków alloferonu zostały przeprowadzone po raz pierwszy. Z kolei poznanie aktywności jamamarinu, niedawno opisanego pentapeptydu wyizolowanego z ćmy Antheraea yamamai, jak i jego analogu, dostarczyło nowych danych odnośnie fizjologicznej roli tego peptydu u owadów. Uzyskane wyniki wskazują, że testowane peptydy modulują aktywność układu immunologicznego zarówno na poziomie odpowiedzi komórkowej, zmieniając aktywność fagocytarną hemocytów oraz ich zdolność do nodulacji, jak i wpływają na odpowiedź typu humoralnego opartą o aktywność oksydazy polifenolowej. Aplikacja obu peptydów oraz ich analogów powodowała zwiększenie liczby hemocytów fagocytujących oraz w sposób stężeniowo-zależny wpływała na proces nodulacji, równocześnie indukując stężeniowo- oraz czasowo-zależne zmiany w odpowiedzi humoralnej. Ponadto, związki te, choć nie wpływały na zdolność hemocytów do adhezji, to w części populacji tych komórek wykazywały działanie pro-apoptotyczne. W trakcie badań wykazano ponadto szerokie i zróżnicowane spektrum oddziaływania badanych peptydów i ich analogów na procesy związane z funkcjonowaniem żeńskiego układu rozrodczego T. molitor. Związki te posiadają właściwości oocytrotropowe, folikulotropowe i wpływają na proces owulacji oraz owipozycji, W kontekście rozwojowym, obserwowano, po ich aplikacji topikalnej w trakcie embriogenezy, działanie embriotoksycznie, prowadzące do redukcji liczby wylęgających się larw. Dodatkowo, iniekcja tych związków powodowała wystąpienie stężeniowo-zależnych zmian w objętości oocytów terminalnych, które nie były jednak powiązane z równoczesnymi zmianami w strukturze nabłonka folikularnego owariolii. Były one raczej skorelowane ze zwiększeniem poziomu ekspresji genu kodującego witelogeninę, białka zapasowego dla rozwijającego się zarodka, w tkance ciała tłuszczowego i jajniku. Ponadto po aplikacji alloferonu oraz jego analogów obserwowano bimodalny, stężeniowo-zależny wpływ tego związku na liczbę składanych jaj. Chociaż wyniki przeprowadzonych badań pokazują wyraźnie immunotropową, gonadotropową i embriotoksyczną aktywność alloferonu i jamamarinu oraz ich peptydomimetyków, to trudno precyzyjnie określić, które z tych rodzajów aktywności są bardziej specyficzne dla jednego lub drugiego peptydu natywnego. Wykonana wstępna analiza współzależności struktura – aktywność fizjologiczna dla obu peptydów zdaje się pokazywać, że modyfikowanie N-końca ich cząsteczki w kierunku bardziej hydrofobowym pozwala otrzymać koniugaty o własnościach agonistów lub antagonistów. Fakt, że oba natywne peptydy wykazują szerokie działanie fizjologiczne dowodzi pośrednio występowania receptora(ów) w tkankach T. molior dla tych peptydów. Poza tym zróżnicowana niekiedy odpowiedź w badanych procesach fizjologicznych podczas działania poszczególnych analogów sugeruje możliwość zmiany w oddziaływaniu analogów z receporem(ami) dla tych peptydów, a także modyfikowania transdukcji sygnału.In the study, immunotropic, gonadotropic and embryotoxic activity of alloferone and yamamarin and their peptidomimetics being conjugates with saturated fatty acids: caprylic acid [C8], myristic [C14] and palmitic [C16], in a heterologous biotest with T. molitor was tested. Studies have shown pleiotropic and differential effects of these compounds on processes related to the functioning of the immune and reproductive system and embryonal development in adult beetles. It should be noted that studies on selected alloferone peptidomimetics were carried out for the first time. In turn, revealed activity of yamamarin, a recently described pentapeptide isolated from Antheraea yamamai moths, as well as its analogue, is the foundation of knowledge about this peptide and its role in insect physiology. The obtained data showed that the tested peptides modulate the activity of the immune system at the cellular level of response, changing the ability of haemocytes to the phagocytosis and nodulation process, as well as at the humoral immunological response based on the action of polyphenol oxidase. Both peptides and their analogues increased the number of phagocytic haemocytes and showed a concentration-dependent effect on the nodulation process. Simultaneously, tested peptides induced concentration- and time-dependent changes in the humoral response in adult beetles. These compounds, although in the initial phase did not affect the ability of haemocytes to adhesion, part of the cell population showed a pro-apoptotic effect. The study also showed a broad and diversified impact spectrum of the tested peptides and their analogues on processes related to the functioning of the female reproductive system of T. molitor. These compounds possess oocytrotropic and follicle stimulating properties. They influence ovulation and egg-laying processes, and in developmental aspect, after topical application they work embryotoxically, reducing the number of hatching larvae. Injections of these compounds caused the occurrence of concentration-dependent changes in the volume of terminal oocytes, which, however, were not related to simultaneous changes in the ovarian follicle epithelium, but rather, they were correlated with the increased expression of the gene encoding the storage protein for the developing embryo - witelogenin. After application of alloferone and its analogues, concentration-dependent bimodal changes in the number of laid eggs were observed. Although the results of the firstly conducted studies show clearly the immunotropic, gonadotropic and embryotoxic activity of alloferone, yamamarin and their peptidomimetics, it is difficult to determine precisely which of these activities are more specific for one or other of the native peptides. The preliminary analysis of the interrelationships structure - physiological activity for both peptides seems to show that modifying the N-terminus of their molecule in a more hydrophobic direction allows to obtain conjugates with agonist or antagonist properties. The fact that both native peptides show a wide physiological effect indirectly proves at the same time the presence of receptor(s) for them in T. molitor tissues. In addition, varied response of studied physiological processes during individual analogues action, suggests the possibility of changing interaction of the analogue with their receptor(s) and modifying signal transduction

Insects as a New Complex Model in Hormonal Basis of Obesity

Nowadays, one of the biggest problems in healthcare is an obesity epidemic. Consumption of cheap and low-quality energy-rich diets, low physical activity, and sedentary work favor an increase in the number of obesity cases within many populations/nations. This is a burden on society, public health, and the economy with many deleterious consequences. Thus, studies concerning this disorder are extremely needed, including searching for new, effective, and fitting models. Obesity may be related, among other factors, to disrupting adipocytes activity, disturbance of metabolic homeostasis, dysregulation of hormonal balance, cardiovascular problems, or disorders in nutrition which may lead to death. Because of the high complexity of obesity, it is not easy to find an ideal model for its studies which will be suitable for genetic and physiological analysis including specification of different compounds’ (hormones, neuropeptides) functions, as well as for signaling pathways analysis. In recent times, in search of new models for human diseases there has been more and more attention paid to insects, especially in neuro-endocrine regulation. It seems that this group of animals might also be a new model for human obesity. There are many arguments that insects are a good, multidirectional, and complex model for this disease. For example, insect models can have similar conservative signaling pathways (e.g., JAK-STAT signaling pathway), the presence of similar hormonal axis (e.g., brain–gut axis), or occurrence of structural and functional homologues between neuropeptides (e.g., neuropeptide F and human neuropeptide Y, insulin-like peptides, and human insulin) compared to humans. Here we give a hint to use insects as a model for obesity that can be used in multiple ways: as a source of genetic and peptidomic data about etiology and development correlated with obesity occurrence as well as a model for novel hormonal-based drug activity and their impact on mechanism of disease occurrence

Solanaceae glycoalkaloids: α-solanine and α-chaconine modify the cardioinhibitory activity of verapamil

Many plants from various genera produce secondary metabolites which have high biological activity as α-solanine and α-chaconine — glycoalkaloids from the Solanaceae family. In plants, they act as a natural weapon against herbivorous and as antipathogenic agents during fungal or bacterial infection. Thus, they are of interest to many researchers searching for new pharmacologically active compounds with the potential for use as drugs in therapies of different diseases. Moreover, they are commonly found in popular agricultural products like tomatoes, potatoes, or eggplants, and therefore, they may be consumed in quite high amounts. Because of their biological activity, glycoalkaloids may interact with many drugs used in therapies of various disorders. In our studies, we wanted to check, if Solanaceae glycoalkaloids, α-solanine, and α-chaconine, interact with popular drug verapamil, a calcium channel blocker used in the treatment of hypertension and as an antiarrhythmic drug, and in this way change its effectiveness. Our studies conducted on insect myocardium showed, that glycoalkaloids act antagonistically to this drug. They decreased the maximal effects evoked by pure verapamil and changed the pharmacokinetic parameters of verapamil action; hence, it seems that the consumption of glycoalkaloid-reach products during verapamil administration should be considering. Moreover, the analysis of L-type calcium channel transcript distribution in insect tissues indicated the presence of two splicing variants, one more present in the myocardium, and the second one in the nervous system

The Dark Side of Iron: The Relationship between Iron, Inflammation and Gut Microbiota in Selected Diseases Associated with Iron Deficiency Anaemia—A Narrative Review

Iron is an indispensable nutrient for life. A lack of it leads to iron deficiency anaemia (IDA), which currently affects about 1.2 billion people worldwide. The primary means of IDA treatment is oral or parenteral iron supplementation. This can be burdened with numerous side effects such as oxidative stress, systemic and local-intestinal inflammation, dysbiosis, carcinogenic processes and gastrointestinal adverse events. Therefore, this review aimed to provide insight into the physiological mechanisms of iron management and investigate the state of knowledge of the relationship between iron supplementation, inflammatory status and changes in gut microbiota milieu in diseases typically complicated with IDA and considered as having an inflammatory background such as in inflammatory bowel disease, colorectal cancer or obesity. Understanding the precise mechanisms critical to iron metabolism and the awareness of serious adverse effects associated with iron supplementation may lead to the provision of better IDA treatment. Well-planned research, specific to each patient category and disease, is needed to find measures and methods to optimise iron treatment and reduce adverse effects

Beetles as Model Organisms in Physiological, Biomedical and Environmental Studies – A Review

Model organisms are often used in biological, medical and environmental research. Among insects, Drosophila melanogaster, Galleria mellonella, Apis mellifera, Bombyx mori, Periplaneta americana, and Locusta migratoria are often used. However, new model organisms still appear. In recent years, an increasing number of insect species has been suggested as model organisms in life sciences research due to their worldwide distribution and environmental significance, the possibility of extrapolating research studies to vertebrates and the relatively low cost of rearing. Beetles are the largest insect order, with their representative – Tribolium castaneum – being the first species with a completely sequenced genome, and seem to be emerging as new potential candidates for model organisms in various studies. Apart from T. castaneum, additional species representing various Coleoptera families, such as Nicrophorus vespilloides, Leptinotarsa decemlineata, Coccinella septempunctata, Poecilus cupreus, Tenebrio molitor and many others, have been used. They are increasingly often included in two major research aspects: biomedical and environmental studies. Biomedical studies focus mainly on unraveling mechanisms of basic life processes, such as feeding, neurotransmission or activity of the immune system, as well as on elucidating the mechanism of different diseases (neurodegenerative, cardiovascular, metabolic, or immunological) using beetles as models. Furthermore, pharmacological bioassays for testing novel biologically active substances in beetles have also been developed. It should be emphasized that beetles are a source of compounds with potential antimicrobial and anticancer activity. Environmental-based studies focus mainly on the development and testing of new potential pesticides of both chemical and natural origin. Additionally, beetles are used as food or for their valuable supplements. Different beetle families are also used as bioindicators. Another important research area using beetles as models is behavioral ecology studies, for instance, parental care. In this paper, we review the current knowledge regarding beetles as model organisms and their practical application in various fields of life science