Delta Sleep-inducing Peptide Research Articles

Modified Effect of Peptide Preparations on Spontaneous Motor Activity in Male Rats under the Conditions of Light Desynchronosis

This study examined the effect of peptide extracts from the epiphysis-pituitary gland of Reindeer (Rangifer tarandus) and a delta sleep-inducing peptide, simulating a modified release of drugs, on the spontaneous motor activity of male rats under the conditions of light desynchronosis. The study revealed changes in spontaneous motor activity under the influence of extracts of a peptide nature and a delta sleep-inducing peptide under the following polar light regimes. Under the conditions of constant lighting and constant darkness, an increase and a decrease in activity was observed, respectively. Under normal lighting, peptide extracts showed increased efficacy. This method of pharmacological adjustment of the body’s circadian oscillators using modified-release peptides can be used to develop a scheme for correcting light desynchronosis.

Delta Sleep-Inducing Peptide Recovers Motor Function in SD Rats after Focal Stroke.

Background and Objectives: Mutual effect of the preliminary and therapeutic intranasal treatment of SD rats with DSIP (8 days) on the outcome of focal stroke, induced with intraluminal middle cerebral occlusion (MCAO), was investigated. Materials and Methods: The groups were the following: MCAO + vehicle, MCAO + DSIP, and SHAM-operated. DSIP or vehicle was applied nasally 60 (±15) minutes prior to the occlusion and for 7 days after reperfusion at dose 120 µg/kg. The battery of behavioral tests was performed on 1, 3, 7, 14, and 21 days after MCAO. Motor coordination and balance and bilateral asymmetry were tested. At the end of the study, animals were euthanized, and their brains were perfused, serial cryoslices were made, and infarction volume in them was calculated. Results: Although brain infarction in DSIP-treated animals was smaller than in vehicle-treated animals, the difference was not significant. However, motor performance in the rotarod test significantly recovered in DSIP-treated animals. Conclusions: Intranasal administration of DSIP in the course of 8 days leads to accelerated recovery of motor functions.

Effects of Delta-sleep-inducing, Kisspeptin-10 and pt-141 Neuropeptides on Sexual Behaviour in Male Rats

The work presents a comparative assessment of the effects of delta-sleep-inducing peptide (DSIP), kiss-peptin-10 and PT-141 neuropeptides on the copulatory behaviour in male rats with natural sexual activity. A single intraperitoneal injection of DSIP (1 mg/kg) promotes the motivational and copulatory components of sexual male rat behaviour in courtship of a receptive female. The neuropeptide application significantly boosts sexual activity in males, rises the copulation rate, mean number of ejaculations towards sexual exhaustion and reduces rest periods in animals. Kisspeptin-10 (1 mg/kg) promotes high arousal in the middle (increased copulation rate in copulatory series 6) and end of the courtship cycle (increased ratio of sexually active males in copulatory series 8-9). PT-141 (0.13 mg/kg) facilitates sexual activity in male rats only in the onset and middle of the courtship cycle. The transience of DSIP and PT-141 stimulating effect warrants adjustments in the neuropeptide dosage and application regimens.

NEUROPEPTIDES EFFECTS ON RAT ESTROUS CYCLE DISORDERS CAUSED BY MORPHINE

The aim of the study was to evaluate the influence of the Delta sleep-inducing peptide (DSIP) or the analogue of the adrenocorticotropin4-10 fragment (FACTH) on changes in the estrous cycle of rats caused by long-term administration of morphine. It has been found that the intranasal administration of DSIP or FACTH for 14 days did not lead to significant changes in the estrous cycle in mature female inbred rats. The introduction of morphine at a dose of 60 mg/kg for 60 days was accompanied by a statistically significant change in the duration and structure of the estrous cycle in experimental animals: a decrease in the duration of the estrus period to 1,50 ± 0,17 days and an increase in interintegration to 8,30 ± 0,80 days, as well as the total duration of the estrous cycle up to 9,60 ± 0,65 days. In turn, the use of DSIP and FACTH for 14 days after the administration of morphine at a dose of 60 mg/kg for 60 days led to the normalization of the structure and duration of the estrous cycle in mature female inbred rats.

Modulatory effects of delta sleep-inducing peptide in a lindane model of generalized seizures

Delta sleep-inducing peptide (DSIP) is an endogenous peptide that is constantly present in several different brain regions. Lindane is used as a pesticide and scabicide, but it also induces seizures refractory to conventional antiepileptics. The aim of this paper was to determine whether DSIP modulates lindane-induced seizures in rats in a behavioral and electroencephalographic (EEG) study. DSIP (1 mg/kg, i.p.) or dimethyl-sulfoxide (DMSO, 0.5 ml/kg, intraperitoneally (i.p.)) were injected 30 min before lindane (8 mg/kg, i.p.) to adult male rats with previously implanted electrodes for EEG registration. During the following 30 min, the EEG was registered, and the following behavioral characteristics of seizures were observed: incidence, latency and intensity. A descriptive scale with grades from 0 to 4 provided an estimate of seizure intensity. In the EEG, the number and duration of ictal periods were analyzed using NeuroSciLaBG (Belgrade, Serbia) software. The lethality rate was also analyzed. DSIP-treated animals showed significantly modified characteristics of lindane-induced seizures when compared to the group without DSIP pretreatment (i.e. a reduced seizure intensity and a prolonged seizure latency period). However, no significant effects of DSIP on seizure incidence and lindane-induced lethality were observed. EEG analyses showed a significantly decreased number of lindane-induced EEG ictal periods in DSIP-treated animals, but with unaltered duration. These results show that DSIP favorably modulates lindane-induced seizures in rats, showing a potential to be an adjuvant component of antiepileptic treatment strategy for refractory seizures.

Expression and Purification of Delta Sleep-Inducing Peptide Fused with Protein Transduction Domain and Human Serum Albumin in Pichia pastoris.

Sleep is a natural part of every individual's life. Delta sleep-inducing peptide (DSIP) is a nonapeptide that could promote sleep through the induction of slow wave sleep. However, little is known about the pharmacological effect of DSIP on insomnia. The main objective of this study was to analyze the pharmacological effect of DSIP on insomnia. We designed a fusion protein containing N-terminal TAT-based transduction domain followed by human serum albumin and DSIP and designated this protein as PHD fusion protein. The PHD fusion protein were expressed in Pichia pastoris and purified. Mice were administered single subcutaneous injections three concentrations of PHD fusion protein (0.5, 1, 2 mg/kg), and the pharmacological activity of PHD fusion protein was studied using classic pentobarbitalinduced sleep test. We expressed the PHD fusion protein in P. pastoris; furthermore, the PHD fused protein was purified to near homogeneity by DEAE Sepharose FF, Phenyl Sepharose HP and Blue Sepharose 6 FF. Our result showed that the increase of pentobarbital-induced hypnotic effect characterized by reducing sleep latency and prolonged sleep duration was observed for increasing concentrations of PHD fusion protein (P<0.05); moreover, different dose of PHD fusion protein could induce the mice to re-sleep in a dose-dependent manner, whereas higher doses of PHD fusion protein (1.0, 2.0 mg/kg) significantly increased the rate of sleep re-onset compared with the vehicle group of mice (P<0.05). PHD fusion protein increased the hypnotic effects of pentobarbital by reducing sleep latency and prolonged sleep duration. The present study suggested PHD fusion protein could be a new drug candidate for insomnia.

STUDY OF THE COMBINED INFLUENCE OF SODIUM THIOPENTAL AND DELTA SLEEP-INDUCING PEPTIDE ON ANTIOXIDANT DEFENSE SYSTEM IN RATS

A biochemical investigation was performed into activity of rat antioxidant defense enzymes at different time interval after administration of sodium thiopental and delta-sleep-inducing peptide (DSIP). It was shown that thiopental coma was accompanied by a decreased level of superoxide dismutase ( 6 and 24 h after exposure) and increased level of caspase-3 ( 6 h after exposure) in the rat blood plasma. A pharmacological correction with DSIP induced a decrease of the level of superoxide dismutase ( 6 and 24 h after exposure), glutathione peroxidase and glucose 6-phosphate dehydrogenase (after 6h).

Effect of Delta Sleep-Inducing Peptide on Functional State of Hepatocytes in Rats During Restraint Stress.

We studied the effect of delta sleep-inducing peptide (40, 120, and 360 μg/kg intraperitoneally, 1 h before the experiment) on free radical oxidation in the liver, aminotransferase activity, and total serum protein content in male Wistar rats during restraint stress. Treatment with the peptide in a dose of 40 μg/kg increased catalase and superoxide dismutase (SOD) activities and malonic dialdehyde (MDA) concentration in the liver homogenate of animals subjected to acute stress. No significant changes were found after administration of this peptide in other doses. Under conditions of chronic stress, the peptide in a dose of 40 μg/kg caused the most pronounced effect. Catalase and SOD activities and MDA concentration decreased, while aminotransferase activity and protein content remained unchanged under these conditions. Administration of the peptide in a dose of 120 μg/kg was accompanied by a decrease in SOD activity and MDA concentration, increase in total protein content, and reduction of AST activity. Increasing the peptide dose to 360 μg/kg abolished its effects.

Морфология печени крыс в условиях острого эмоционально-болевого стресса на фоне введения дельта-сон индуцирующего пептида

An acute foot-shock stress caused a reduction in parenchymal-stromal ratio due to the dilation and hyperemia of the liver blood vessels, a stagnation phenomenon in the bile capillaries and cholestasis, an increase in the intensity of the liver current functioning and development of degenerative and destructive changes in hepatocytes, an increase in the current proliferative activity of hepatocytes along with the reduced depth of reparative reserves according to the results of the morphometric examination of the liver. Delta sleep-inducing peptide (DSIP) in the every dose used (40, 120, and 360 mcg/kg) increased the parenchymal-stromal ratio indicators in stressed animals. Peptide introduction in a dose of 40 mcg/kg was accompanied by increasing the current rate of functioning hepatocytes and accumulating the potential reparative reserves in stressed animals. DSIP in a dose of 360 mcg/kg contributed to a decrease in hyperemia, stagnation phenomenon and cholestasis, a significant reduction in degenerative processes and an increase in the liver reparative reserves. In conditions of the acute foot-shock stress the thymus relative weight was also reduced, but it was leveled after administrating DSIP in doses of 40 and 360 mcg/kg. Thus both the stress and peptide administration had no effect on the relative liver weight.

Role of phosphorylated delta sleep inducing peptide (p-DSIP) on sleep architecture and spatial memory impairment of rats under chronic hypobaric hypoxia

Event Abstract Back to Event Role of phosphorylated delta sleep inducing peptide (p-DSIP) on sleep architecture and spatial memory impairment of rats under chronic hypobaric hypoxia Koustav Roy1, Krishna Kishore1*, Koushik Ray1, Meetu Wadhwa1, Vishal Jain1, Garima Chauhan1, Punita Kumari1, Shahnawaz Alam1, Usha Panjwani1 and Shashi Bala Singh1 1 Defence Institute of Physiology and Allied Sciences (DIPAS), Defence Research and Development Organization (DRDO), Neurophysiology, India Sleep architecture alteration is one of the causes for sleep deprivation at high altitude. Hypobaric hypoxia (HH) affects non rapid eye movement sleep (NREM) followed by alteration in rapid eye movement sleep. NREM plays major role in spatial memory. Delta sleep inducing peptide (DSIP) is a well known peptide playing a role in improving sleep quality. Previous studies have shown HH induced memory impairments but its correlation with sleep deprivation is still need to be understood. The present study was designed to evaluate the role of sleep in HH induced cognitive declined. Animals were exposed to HH stress at 25,000 feet for continuous 7 days. P-DSIP was given as intervention at a dose of 10µg/kg/day for positive control. Norepinephrine (NE), serotonin and dopamine (DA) levels were measured from hippocampus, cortex, brain stem and hypothalamus by HPLC. Result showed that concentration of NE and DA were more increased after chronic hypoxia than control group. The finding may be due to over activity of tyrosine hydroxylase. Serotonin level was decreased in hypoxia group. It may be casued by the less activity of tryptophan hydroxylase as it is more sensitive to oxygen than monoamine oxidase (MAO). On the other hand, in p-DSIP treated group NE and DA levels significantly decrease than without drug treated group and serotonin level was significantly increases. Morris water maze (MWM) performance was significantly improved in p-DSIP treated hypoxic rats than only hypoxia group. MWM performance improvement may be due to improvement of serotonin level in drug treated group. P-DSIP has a major possibility to improve quality of sleep in drug treated group, which may directly play a positive role in MWM performance. Keywords: Memory, Sleep, neurotransmitters, in vivo, hypobaric hypoxia Conference: 14th Meeting of the Asian-Pacific Society for Neurochemistry, Kuala Lumpur, Malaysia, 27 Aug - 30 Aug, 2016. Presentation Type: Poster Presentation Session Topic: 14th Meeting of the Asian-Pacific Society for Neurochemistry Citation: Roy K, Kishore K, Ray K, Wadhwa M, Jain V, Chauhan G, Kumari P, Alam S, Panjwani U and Singh S (2016). Role of phosphorylated delta sleep inducing peptide (p-DSIP) on sleep architecture and spatial memory impairment of rats under chronic hypobaric hypoxia. Conference Abstract: 14th Meeting of the Asian-Pacific Society for Neurochemistry. doi: 10.3389/conf.fncel.2016.36.00138 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 04 Aug 2016; Published Online: 11 Aug 2016. * Correspondence: Dr. Krishna Kishore, Defence Institute of Physiology and Allied Sciences (DIPAS), Defence Research and Development Organization (DRDO), Neurophysiology, Delhi, Delhi, India, kishu16in@yahoo.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Koustav Roy Krishna Kishore Koushik Ray Meetu Wadhwa Vishal Jain Garima Chauhan Punita Kumari Shahnawaz Alam Usha Panjwani Shashi Bala Singh Google Koustav Roy Krishna Kishore Koushik Ray Meetu Wadhwa Vishal Jain Garima Chauhan Punita Kumari Shahnawaz Alam Usha Panjwani Shashi Bala Singh Google Scholar Koustav Roy Krishna Kishore Koushik Ray Meetu Wadhwa Vishal Jain Garima Chauhan Punita Kumari Shahnawaz Alam Usha Panjwani Shashi Bala Singh PubMed Koustav Roy Krishna Kishore Koushik Ray Meetu Wadhwa Vishal Jain Garima Chauhan Punita Kumari Shahnawaz Alam Usha Panjwani Shashi Bala Singh Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Enzymatic attributes of an l-isoaspartyl methyltransferase from Candida utilis and its role in cell survival

BackgroundsSpontaneous deamidation and isoaspartate (IsoAsp) formation contributes to aging and reduced longevity in cells. A protein-l-isoaspartate (d-aspartate) O-methyltransferase (PCMT) is responsible for minimizing IsoAsp moieties in most organisms. MethodsPCMT was purified in its native form from yeast Candida utilis. The role of the native PCMT in cell survival and protein repair was investigated by manipulating intracellular PCMT levels with Oxidized Adenosine (AdOx) and Lithium Chloride (LiCl). Proteomic Identification of possible cellular targets was carried out using 2-dimensional gel electrophoresis, followed by on-Blot methylation and mass spectrometric analysis. ResultsThe 25.4kDa native PCMT from C. utilis was found to have a Km of 3.5µM for AdoMet and 33.36µM for IsoAsp containing Delta Sleep Inducing Peptide (DSIP) at pH 7.0. Native PCMT comprises of 232 amino acids which is coded by a 698bp long nucleotide sequence. Phylogenetic comparison revealed the PCMT to be related more closely with the prokaryotic homologs. Increase in PCMT levels in vivo correlated with increased cell survival under physiological stresses. PCMT expression was seen to be linked with increased intracellular reactive oxygen species (ROS) concentration. Proteomic identification of possible cellular substrates revealed that PCMT interacts with proteins mainly involved with cellular housekeeping. PCMT effected both functional and structural repair in aged proteins in vitro. General significanceIdentification of PCMT in unicellular eukaryotes like C. utilis promises to make investigations into its control machinery easier owing to the familiarity and flexibility of the system.

Influence of delta-sleep inducing peptide on the state of lysosomal membranes and the intensity of lysosomal proteolysis in different rat tissues with physiological aging of the organism

It is shown that subcutaneous injection of exogenous delta-sleep inducing peptide (DSIP) in rats aged 2–24 months at a dose of 100 μg/kg animal body weight in courses of 5 consecutive days per month has a stabilizing effect on the state of lysosomal membranes in rat tissues (brain, heart muscle, and liver) at different ontogenetic stages, and this effect is accompanied by an increased intensity of lysosomal proteolysis in these tissues.

Influence of delta-sleep peptide on the enzymatic activity of the mitochondrial electron transport chain in various rat tissues with aging of the organism

It is shown that subcutaneous injection of exogenous delta-sleep inducing peptide (DSIP) to rats aged 2-24 months in a dose of 100 μg/kg animal body weight by courses of 5 consecutive days per month has a stabilizing effect on the NADH-dehydrogenase activity in the mitochondrial fractions of various tissues, which together with increasing capacity of the antioxidant system should reduce the production of free radicals and their adverse action on cells macromolecule, herewith the activity of succinate dehydrogenase did not change.

The infl uence of the treatment with deltalycyn on clinical, functional and morphological manifestations of diabetic retinopathy

Aim. Protective effects of delta sleep-inducing peptide (DSIP) on retinopathy has been shown earlier on the model of streptozotocin diabetes mellitus. 52 patients with non-prolypherative form of diabetic retinopathy (DR) were prescribed treatment with deltalcyn intranasal administration– drug, which was composed on the DSIP basis. This medication was taken during month twice per half of year.Methods and results. Severity of DR was 20 – 35 units in accordance to ETDRS scale. It was established that in half of year index of optical density of macular pigment, which was determined in heterochrome fl icker – photometry test, increased by 32,4% (P&lt;0.05) in compare to control group of patients (traditional treatment of 35 patients with DR). And exceeded the index which was registered before treatment by35,1% (P&lt;0.05). Vision acuteness increased by9,4 % (P&lt;0,05), along with the reduction of the number of created microaneurisms – by 16,4% (P&lt;0,05). It was observed during this period.Conclusion. Deltalycyn possessed protective activity against not-prolypherative form of DR.

Neurodegenrative changes in retina of rats with streptozotocin diabetes under different conditions of experimental treatment

Introduction . Diabetic retinopathy pathogenesis includes mechanisms of free radical generation and intensification of lipid peroxidation. It was shown that electrical stimulation (ES) of cerbellar structures as well as administration of delta-sleep inducing peptide (DSIP) is able both to alleviate intensified lipid peroxidation and cause neuroprotective action in neuronal tissue. The aim of research was to investigate the effectiveness of combined usage of DSIP and ES of paleocerebellar cortex upon neurodegenerative manifestations in retina of rats suffered from streptozotocin (STZ)- induced diabetes. Methods of investigations . In Wistar rats diabetes have been modeled via i.p. STZ administration (55,0 mg/kg, i.p.). Electrical stimulations (ES) (100 Hz, 0,25 ms, 80-120 mcA, 2,5 s) of paleocerebellar cortex (V-VII lobules), which have been delivered during ten weeks two times daily (9.00; 19.00), started on 15 th day from the moment of STZ injection. DSIP («Sigma-Aldrich Chemie GmbH», Germany) have been administered every third day during ten weeks in a dosage of 50 mcg/ kg, i.p. Separate group of STZ-treated rats have been provided with combined usage of DSIP and ES in mentioned dosage and regimen during ten weeks. Retinal hemotoxylin eosin painted slices (5 mcm) have been used for light microscopy and calculation of the number of neurons in retinal layers using digital photos. Results have been expressed as number of cells/mm 2 + SEM. Results . Histological investigation of retina of rats with STZ diabetes revealed the net neurons vacuolization, along with edematic and picnotic deteriorations of neurons. Such disturbances were absent in intact rats and also less pronounced in groups of rats treated with DSIP and paleocerebellar ES. In rats with STZ-induced diabetes the outer nuclear layer contained less number of neurons – by 35,4% when compared with the same index in intact animals (P 0,05). The number of neurons in the retinal inner nuclear layer of STZ-treated rats was reduced by 2,2 times pertained to intact rats (P<0,05). In groups of rats with DSIP administration and paleocerebellar ES the reduction was 1,94 and 1,8 times correspondently when compared with the intact rats (P<0,05). Combined usage of DSIP and paleocerebellar ES was followed by the prevalence in number of neurons by 53,1% pertained to the similar index in STZ-treated animals (P<0,05). At the same time the number of neurons in inner nuclear layer was still diminished by 30,8% when compared to intact animals (P<0,05). The number of neurons in retinal ganglionar layer in STZ- treated rats was reduced by 2,1 times in comparison with the similar data in intact rats (P<0,05). The reduction of investigated index by 1,79 and 1,93 times was observed in diabetic rats treated with DSIP and ES correspondently (P<0,05). Combined usage of DSIP and ES in STZ-treated rats was followed by prevalence of the number of neurons by 36,9% when compared to the data in STZ-treated rats (P<0,05). At the same time the investigated index was reduced by 34,4% in comparison with the such one registered in intact animals (P<0,05). Conclusions. 1.The development of STZ-induced diabetes is connected with neurodegenerative changes in retina, which is most pronounced in the outer nuclear layer. 2. The combined usage of DSIP and ES of paleocerebellar cortex is followed by the pronounced neurtoprotective action under condition of experimental STZ- induced diabetes.

Effect of Delta Sleep-Inducing Peptide on the Expression of Antioxidant Enzyme Genes in the Brain and Blood of Rats during Physiological Aging

Subcutaneous injections of exogenous delta sleep-inducing peptide in a dose of 100 μg/kg (monthly, 5-day courses) to rats of various age groups (2-24 months) were followed by an increase in the expression of genes for SOD 1 (Sod1) and glutathione peroxidase 1 (Gpx1) in the brain and nucleated blood cells. The expression of these genes was shown to decrease during physiological aging of the body.

Delta-sleep inducing peptide entrapment in the charged macroporous matrices

Various biomolecules, for example proteins, peptides etc., entrapped in polymer matrices, impact interactions between matrix and cells, including stimulation of cell adhesion and proliferation. Delta-sleep inducing peptide (DSIP) possesses numerous beneficial properties, including its abilities in burn treatment and neuronal protection. DSIP entrapment in two macroporous polymer matrices based on copolymer of dimethylaminoethyl methacrylate and methylen-bis-acrylamide (Co-DMAEMA-MBAA) and copolymer of acrylic acid and methylen-bis-acrylamide (Co-AA-MBAA) has been studied. Quite 100% of DSIP has been entrapped into positively charged Co-DMAEMA-MBAA matrix, while the quantity of DSIP adsorbed on negatively charged Co-AA-MBAA was only 2–6%. DSIP release from Co-DMAEMA-MBAA was observed in saline solutions (0.9% NaCl and PBS) while there was no DSIP release in water or 25% ethanol, thus ionic strength was a reason of this process.

Streptozotocin-Induced Diabetes-Related Changes in the Functional State of the Rat Retina: Possibilities for Correction Using Delta Sleep-Inducing Peptide

Three months after single injection of streptozotocin (50.0 mg/kg, i.p.), average activities of superoxide dismutase (SOD) and glutathione reductase (GTR) in tissues of the retina of Wistar rats were lower by 47.5 and 42.2%, respectively, while the content of malondialdehyde (MDA) was about 330% of the norm. Recording of electroretinogram (ERG) showed that the amplitude of wave a in these animals was significantly lower (by 57.3%), while the latencies of waves a and b exceeded normal values by 27.5 and 11.8 %, respectively (P < 0.05). After injections of δ sleep-inducing peptide (δSIP, 0.05 mg/kg, i.p., once every three days for two months), SOD and GTR activities did not differ significantly from normal values, while the MDA level was higher by 53.7% (P < 0.05). The mean amplitude of ERG wave a demonstrated no considerable difference from the norm; at the same time, the latencies of waves a and b still exceeded normal values by 13.2 and 10.4 %, respectively. Therefore, negative changes in the functional state of the retina observed because of the development of diabetic retinopathy undergo noticeable moderation under the influence of δSIP.

The KND olygopeptide as a putative endogenous prototype of Delta Sleep Inducing Peptide (DSIP). comparative study of biological properties

We have undertaken a comparative study on physiological activity of well known neuropeptide DSIP (WAGGDASG E) and new closely related peptide KND (WKGGNASGE) in vivo assays. The sequence of K2, N5-DSIP (KND) was found recently by the computer search for DSIP homologous sequences in available nucleotide and protein databases at 324-332 site of Lysine-specific demethylase 3 B (EC 1.14.11, Swiss-Prot: Q7LBC6.1, 1-1761aa). This human lysine-specific histone demethylase is a representative of the recently discovered family of so called JmjC-domain-containing histone demethylases encoded by JMJD1B gene and ubiquitously expressed in tissues of various mammalian species. Biological investigations performed in this work confirm our preliminary data that DSIP-related peptide KND exhibits the similar biological properties in comparison with DSIP. Assessed by us antioxidative, anticonvulsive and behavioral effects of KND were even more expressed than in DSIP case. These results provide the additional evidences to support our suggestion that KND can be a possible endogenous prototype of "real" DSIP.

Effect of delta-sleep-inducing peptide on the functional activity of certain organs and tissues of rats in the physiological aging of an organism

This paper shows that the exogenous delta-sleep-inducing peptide (DSIP) injected subcutaneously into rats at an age of 2–24 months of postnatal development in a dose of 100 mg/kg of animal body weight in courses for five consecutive days each month has a hepatoprotective effect. DSIP does not affect the functional activity of the pancreas and is not involved in the regulation of calcium homeostasis in the physiological aging of an organism.