Effects Of Short Peptides Research Articles

The effect of short peptides on the growth and yield of soybeans

Aim. Study of the effect of short di‐ and tetrapeptides (AB‐0, AE‐0) on the growth, development and productivity of Batya soybean varieties.Material and Methods. Biologically active dipeptide AB‐0 and tetrapeptide AE‐0 were used. Field studies were carried out on meadow‐brown podzolized gley heavy loamy soil. One month before planting, soybean seeds were treated with dipeptide/tetrapeptide of concentrations of 0.01 g/l or 0.001 g/l. Hand‐tended and industrial‐level research was carried out.Results. The use of dipeptide AB‐0 in a hand‐tended study had a positive effect on the growth processes of soybeans of the Batya variety compared to the control. The use of tetrapeptide AE‐0 in a hand‐tended study increased the weight of plants by 7.3‐67.0 g and plant height by 3.0‐9.0 cm compared to the control. The use of dipeptide AB‐0 and tetrapeptide AE‐0 increased the yield of soybeans by a maximum of 81.2‐83.7% compared to the control. The use of peptides AB‐0 and AE‐0 in an industrial‐level experiment increased the yield by 30.5% and 18.4%, respectively, compared with the control.Conclusion. The short peptides AB‐0 and AE‐0 studied had an impact on the growth, development and productivity of Batya soybean varieties. They can be classified as plant growth regulators.

Effect of short peptides on neuronal differentiation of stem cells.

It has been demonstrated that short peptides play an important role in the transmission of biological information, modulation of transcription, and restoring genetically conditioned alterations occurring with age. Peptidergic regulation of homeostasis occupies an important place in physiological processes, which lead to the aging of cells, tissues, and organs, consisting in the involution of major regulatory systems—the nervous, the endocrine, and the immune. The effect of AED (Ala-Glu-Asp), KED (Lys-Glu-Asp), KE (Lys-Glu), AEDG (Ala-Glu-Asp-Gly) peptides and their compound on neuronal differentiation of human periodontal ligament stem cells (hPDLSCs) was studied by immunofluorescence and western blot analysis. Growth-Associated Protein 43 (GAP43), which implements neurotransmission mechanisms and neuroplasticity, demonstrated an increased expression in hPDLSCs cultured with a compound of all studied peptides and with KED alone. The peptide compound and KED, increase the expression of Nestin (neurofilament protein), expressed in early neuronal precursors in hPDLSCs cultures. Thus, the compound of peptides AEDG, KE, AED, and KED could promote the neuronal differentiation of hPDLSCs and be a promising tool for the study of peptides as a modulator of neurogenesis in neurodegenerative diseases studied in animal models.

Effect of Short Peptides on Expression of Signaling Molecules in Organotypic Pineal Cell Culture

We demonstrated the influence of short peptides on the expression of signaling molecules in organotypic culture of the pineal gland from 3-month-old rats. Peptides Ala-Glu-Asp-Gly and Lys-Glu-Asp stimulate the expression of proliferative protein Ki-67 in pineal gland culture. These peptides as well as Glu-Asp-Arg and Lys-Glu do not affect the expression of apoptosis marker AIF. The synthesis of transcription factor CGRP by pinealocytes was stimulated only by Ala-Glu-Asp-Gly. Thus, peptide Ala-Glu-Asp-Gly tissue-specifically stimulates proliferative and secretory activities of pinealocytes, which can be used for recovery of pineal gland functions at the molecular level.

Short Membrane Active (Lipo)-peptides - Interplay Of Domain Formation, Membrane Curvature Stress And Cellular Leakage

The effect of short peptides, derived from lactoferricin, a human host defense peptide exhibiting antibacterial activity and their N-acylated derivatives was studied with biological and membrane mimetic systems. The work carried out during the European RTD-Project “ANEPID” revealed correlation between biological activity against E.coli and interaction with negatively charged lipid model systems, leading to formation of peptide effected lipid domains. Increase of hydrophobicity by addition of hydrophobic amino acids as well as N-acylation improved activity in model and biological systems, but was limited by loss of selectivity for bacterial systems.

Neuroprotective effects of short peptides derived from the Insulin-like growth factor 1

Insulin-like growth factor I (IGF-1) is a peptide synthesized in response to growth hormone stimulation. While most of the circulating IGF-1 comes from the liver, it can also be produced in other tissues and both its expression and processing undergo tissue-specific regulation. The predominant form, IGF-1Ea is a circulating factor while two others, IGF-1Eb and IGF-1Ec (MGF), are mostly expressed in different tissues or in response to various stimuli and show some preferences with respect to the signal transduction pathways they activate. In skeletal muscle specific forms of IGF-1 play a role in development and growth and in addition to these physiological roles IGF-1 functions in the damaged muscle. IGF-1 is also important for the developing and adult brain and can reduce neuronal death caused by different types of injuries. Like many other peptide hormones IGF-1 originates from a precursor pro-hormone that undergoes extensive post-translational modifications. Processing liberates the mature peptide, which acts via the specific IGF-1 receptor but additional short peptides can arise from both N- and C-termini of various IGF-1 isoforms. These derivatives function as autonomous biologically active peptides and extremely potent neuroprotective agents. Their biological effects are independent of the activation of the IGF-1 receptor. Unfortunately, little is known about their mechanism(s) of action. Likewise, the existence of the endogenous production and wider biological effects of these short peptides are uncertain. However, considering the difference in the modes of action it might be possible to dissociate the unwanted and potentially dangerous mitogenic activity of the full-length IGF-1 exerted via its receptor from the neuroprotective effects of short derivatives mediated through different pathways. Such small molecules show good penetration through the blood brain barrier, can be inexpensively manufactured and modified to increase their stability. Therefore, they are good candidates for development into a neuroprotective therapeutic modality.

Production of lymphocyte-activating factors by mouse macrophages during aging and under the effect of short peptides

Age-specific characteristics of production of lymphocyte-activating factor by mouse peritoneal macrophages and modulation of this production by short synthetic peptides (Vilon, Epithalon, and Cortagen) were studied. The production of lymphocyte-activating factors by macrophages stimulated with lipopolysaccharides in vitro was lower in old animals. The opposite modulating effects of short peptides on the production of lymphocyte-activating factors by resident and lipopolysaccharide-stimulated macrophages in young and old mice were demonstrated for the first time. This is a possible mechanism of immune system dysfunction during aging, which opens new vistas for its correction with short synthetic peptides.

Effects of short peptides on lymphocyte chromatin in senile subjects.

Effects of synthetic short peptides (Vilon, Epithalon, Livagen, Prostamax, and Cortagen) on activity of ribosome genes, parameters of common heterochromatin melting, polymorphism of structural heterochromatin (C segments) of chromosomes 1, 9, and 16, and variability of facultative heterochromatin were studied in leukocytes of subjects aged 75-88 years. All the studied peptides induced activation of ribosome genes, decondensation of densely packed chromatin fibrils, and release of genes repressed as a result of age-specific condensation of the cellular euchromatin regions (deheterochromatinization of facultative chromatin). Treatment with Epithalon, Livagen, and Prostamax led to decondensation of chromosome 1 pericentromeric structural chromatin, while Epithalon and Livagen treatment led to changes in chromosome 9 as well. Hence, short peptides activate heterochromatin and heterochromatinized regions of cell chromosomes in senile subjects.

Effects of short peptides on thymocyte blast transformation and signal transduction along the sphingomyelin pathway.

Immunomodulating effects of synthetic peptides Vilon (Lys-Glu), Epithalon (Ala-Glu-Asp-Gly), and Cortagen (Ala-Glu-Asp-Pro) and possible involvement of the sphingomyelin signal transduction pathway in their effects in mouse thymocytes were studied. Vilon produced the most potent comitogenic effect on thymocyte proliferation and modulated comitogenic activity of interleukin-1b. Epithalon was less potent, while Cortagen produced no such effects. Vilon produced a more pronounced stimulatory effect on sphingomyelinase activity in mouse thymocyte membranes compared to Epithalon and Cortagen.