Browse more peptide research, methods and limitations.
Intranasal NPY promoted sleep and reduced ACTH and cortisol in healthy young men, demonstrating CRH-opposing anxiolytic and sedative effects with potential therapeutic applications for depression and insomnia.
Antonijevic, I A; Murck, H; Bohlhalter, S; Frieboes, R M; Holsboer, F; Steiger, A · RCT
Arginine-rich hexapeptides identified from peptide libraries blocked VEGF from binding to its receptor (IC50 = 2–4 micromolar) and selectively inhibited VEGF-driven blood vessel growth without toxicity to normal cells. In animal models, the peptides stopped new blood vessel formation in both chick membrane and rabbit cornea assays. Most notably, one hexapeptide (RRKRRR) blocked both the growth and spread of human colon cancer cells implanted in mice.
Bae, D G; Gho, Y S; Yoon, W H; Chae, C B · Preclinical
Chemical ablation of noradrenergic neurons did not prevent GH secretagogue-induced Fos expression in the arcuate nucleus or brainstem, demonstrating a non-noradrenergic activation pathway.
Bailey, A R; von Engelhardt, N; Leng, G; Smith, R G; Dickson, S L · Animal Study
The heart produces and locally utilizes enkephalins, dynorphins, and endorphins as autocrine/paracrine cardioprotective factors, potentially mediating ischemic preconditioning.
Barron, B A · Review
The minimal active ghrelin fragment is the first 4 amino acids (GSSF) with octanoyl modification on Ser3; the fatty acid modification is essential while most of the 28-residue chain is dispensable for receptor activation.
Bednarek, M A; Feighner, S D; Pong, S S; McKee, K K; Hreniuk, D L; Silva, M V; Warren, V A; Howard, A D; Van Der Ploeg, L H; Heck, J V · In Vitro
Thymosin alpha-1 (0.01-10 μg SC daily for 7 days) increased thymocytes and blood cells, reduced primary tumor weight, and inhibited organ colonization by metastatic cells in tumor-bearing BALB/c mice.
Beuth, J; Schierholz, J M; Mayer, G · Animal Study
Thymic hormones serve dual roles in oncology: as biomarkers correlating with immune status and prognosis, and as therapeutic immunostimulants that enhance anti-tumor immunity when combined with conventional cancer treatments.
Bodey, B; Bodey, B; Siegel, S E; Kaiser, H E · Review
Intracerebroventricular dynorphin antibodies completely blocked nitrous oxide antinociception, proving that N2O analgesic effect is mediated by neuronal release of endogenous dynorphin activating kappa opioid receptors.
Branda, E M; Ramza, J T; Cahill, F J; Tseng, L F; Quock, R M · Animal Study
Food intake regulation involves convergent afferent signals from gut peptides (CCK, GLP-1, PYY, ghrelin), adipose tissue (leptin), vagal mechanoreceptors, and higher brain centers, all integrated by hypothalamic circuitry.
Bray, G A · Review
Intrathecal anti-dynorphin antibodies blocked nitrous oxide antinociception, while anti-enkephalin and anti-endorphin antibodies did not, confirming spinal dynorphin release mediates N2O analgesia at the spinal cord level.
Cahill, F J; Ellenberger, E A; Mueller, J L; Tseng, L F; Quock, R M · Animal Study
Specific GHS binding sites were detected in normal and neoplastic human thyroid tissue, with highest density in medullary thyroid carcinoma, suggesting GH secretagogues may affect thyroid biology and that GHS-R could serve as a thyroid cancer marker.
Cassoni, P; Papotti, M; Catapano, F; Ghè, C; Deghenghi, R; Ghigo, E; Muccioli, G · In Vitro
Alpha-MSH and its C-terminal tripeptide fragment KPV demonstrated direct antimicrobial activity against S. aureus, C. albicans, and E. coli, establishing a dual anti-inflammatory/antimicrobial function for this neuropeptide.
Catania, A; Cutuli, M; Garofalo, L; Carlin, A; Airaghi, L; Barcellini, W; Lipton, J M · In Vitro
In the efficacy trial, nesiritide infused at 0.015 and 0.030 μg/kg/min reduced pulmonary-capillary wedge pressure by 6.0 and 9.6 mmHg respectively, compared to a 2.0 mmHg increase with placebo (p < 0.001). Clinical status improved in 60% and 67% of nesiritide patients versus 14% with placebo (p < 0.001). Dyspnea improved in 57% and 53% versus 12% (p < 0.001), and fatigue improved in 32% and 38% versus 5% (p < 0.001). In the comparative trial, nesiritide's improvements in clinical status, dyspnea, and fatigue were sustained for up to seven days and were comparable to standard intravenous heart failure therapy. The most common adverse effect was dose-related hypotension, which was usually asymptomatic.
Colucci, W S; Elkayam, U; Horton, D P; Abraham, W T; Bourge, R C; Johnson, A D; Wagoner, L E; Givertz, M M; Liang, C S; Neibaur, M; Haught, W H; LeJemtel, T H · Randomized Controlled Trial
Alpha-MSH and KPV demonstrated broad-spectrum antimicrobial activity including against MRSA and drug-resistant organisms, with an anti-Candida mechanism resembling amphotericin B membrane disruption.
Cutuli, M; Cristiani, S; Lipton, J M; Catania, A · In Vitro
Acyclic permutants of kalata B1 folded into native-like cystine knot structures without the circular backbone, but backbone cyclization was required for full biological activity and optimal structural stability.
Daly, N L; Craik, D J · In Vitro
Thymosin alpha-1 combined with low-dose IFN or IL-2 shows high efficacy against cancers in both preclinical models and human clinical trials, supporting its role as a cancer immunotherapy adjuvant.
Garaci, E; Pica, F; Rasi, G; Favalli, C · Review
Three macrocyclic trypsin inhibitors (MCoTI-I, -II, -III) from Momordica cochinchinensis are the smallest known naturally cyclic peptides, with atypical backbone cyclization and potent trypsin inhibition.
Hernandez, J F; Gagnon, J; Chiche, L; Nguyen, T M; Andrieu, J P; Heitz, A; Trinh Hong, T; Pham, T T; Le Nguyen, D · In Vitro
Self-assembling peptide scaffolds supported extensive neurite outgrowth and formation of active, functional synapses, demonstrating programmable peptide-based materials for neural regeneration.
Holmes, T C; de Lacalle, S; Su, X; Liu, G; Rich, A; Zhang, S · In Vitro
Alpha-MSH modulates inflammation through melanocortin receptor-mediated inhibition of NF-κB signaling, reducing pro-inflammatory cytokines, fever, and immune activation in both peripheral tissues and the central nervous system.
Ichiyama, T; Sato, S; Okada, K; Catania, A; Lipton, J M · Review
IL-2 contains a structural domain resembling opioid peptides around its 45th Tyr residue that mediates analgesic effects, blocked by anti-opioid antibodies, revealing molecular overlap between immune and opioid signaling.
Jiang, C L; Xu, D; Lu, C L; Wang, Y X; You, Z D; Liu, X Y · In Vitro
Chronic nandrolone treatment altered met-enkephalin and dynorphin concentrations in limbic and striatal brain regions, providing a neurochemical mechanism for steroid-associated mood and behavioral disturbances.
Johansson, P; Hallberg, M; Kindlundh, A; Nyberg, F · Animal Study
Obese Zucker rats had reduced arcuate POMC mRNA and PVN alpha-MSH levels compared to lean controls, indicating impaired melanocortin satiety signaling as a driver of genetic obesity.
Kim, E M; O'Hare, E; Grace, M K; Welch, C C; Billington, C J; Levine, A S · Animal Study
BNP increased acutely and much more prominently than ANP during coronary angioplasty, with serial changes correlating with procedural myocardial stress, confirming BNP as the superior acute cardiac biomarker.
Kyriakides, Z S; Markianos, M; Michalis, L; Antoniadis, A; Nikolaou, N I; Kremastinos, D T · Cohort
Hypoxia induced coordinated upregulation of adrenomedullin and its receptor RDC-1 in brain astrocytes and endothelial cells, with NF-κB-mediated transcriptional activation, suggesting an autocrine/paracrine protective mechanism at the blood-brain barrier.
Ladoux, A; Frelin, C · In Vitro
Repeated ethanol produced both short-term (24h) and persistent (2-week) alterations in enkephalin and dynorphin tissue concentrations in mesolimbic reward regions, providing a neurochemical basis for alcohol craving and relapse.
Lindholm, S; Ploj, K; Franck, J; Nylander, I · Animal Study
Elevated pre-cardioversion BNP and ANP predicted atrial fibrillation recurrence after DC cardioversion in mild CHF patients, and BNP declined after successful rhythm restoration.
Mabuchi, N; Tsutamoto, T; Maeda, K; Kinoshita, M · Cohort
The combined GHRP-6 + GHRH stimulation test accurately diagnosed adult GH deficiency with high sensitivity and specificity, requiring a single blood draw at 15-30 minutes and avoiding the risks of insulin-induced hypoglycemia.
Mahajan, T; Lightman, S L · Clinical Trial
BNP, ANP, and Big Endothelin-1 each independently correlated with heart failure severity but reflected different pathophysiological aspects — cardiac volume overload versus vascular/renal dysfunction — providing complementary clinical information.
Masson, S; Gorini, M; Salio, M; Lucci, D; Latini, R; Maggioni, A P · Cohort
Adrenomedullin dilates blood vessels through dual mechanisms — direct smooth muscle relaxation and endothelial NO release — with autocrine/paracrine production by vascular endothelial and smooth muscle cells.
Minamino, N; Kangawa, K; Matsuo, H · Review
Melatonin directly regulates thymosin alpha-1 and thymulin production, driving their nocturnal peaks in serum and thymus. Pinealectomy abolished and melatonin replacement restored the circadian thymic peptide pattern.
Molinero, P; Soutto, M; Benot, S; Hmadcha, A; Guerrero, J M · Animal Study
Special forces soldiers showed higher plasma NPY during extreme stress and faster post-stress recovery compared to regular troops, with higher NPY correlating with better performance and less psychological distress.
Morgan, C A; Wang, S; Southwick, S M; Rasmusson, A; Hazlett, G; Hauger, R L; Charney, D S · Cohort
Oral AOD9604 — a synthetic peptide fragment based on the fat-burning region of human growth hormone — reduced weight gain by over 50% in obese Zucker rats. Treated animals gained only 15.8 g versus 35.6 g in controls over 19 days of daily oral dosing at 500 µg/kg body weight. Fat tissue from treated animals showed increased lipolytic (fat-breaking) activity. Critically, unlike full-length growth hormone (which is known to worsen insulin resistance with chronic use), AOD9604 showed no adverse effects on insulin sensitivity when tested with euglycemic clamp techniques — considered the gold standard for measuring insulin action. This separation of fat-burning benefits from growth hormone's diabetogenic side effects was the key finding.
Ng, F M; Sun, J; Sharma, L; Libinaka, R; Jiang, W J; Gianello, R · Animal Study
Endomorphin-2 produces analgesia through both direct mu-opioid receptor activation and indirect dynorphin A release activating kappa receptors via descending pain pathways, while endomorphin-1 uses only the mu pathway.
Ohsawa, M; Mizoguchi, H; Narita, M; Chu, M; Nagase, H; Tseng, L F · Animal Study
Persistent BNP elevation after anthracycline chemotherapy predicted development of cardiotoxicity, distinguishing at-risk patients from those with only transient, benign BNP rises.
Okumura, H; Iuchi, K; Yoshida, T; Nakamura, S; Takeshima, M; Takamatsu, H; Ikeno, A; Usuda, K; Ishikawa, T; Ohtake, S; Matsuda, T · Cohort
Specific GHS binding sites identified in human adrenal, gonadal (ovary/testis), cardiac, and vascular tissues, with ghrelin confirmed as an endogenous ligand at these sites.
Papotti, M; Ghè, C; Cassoni, P; Catapano, F; Deghenghi, R; Ghigo, E; Muccioli, G · In Vitro
Hybrid CCK-A agonist peptides combining structural features of hexapeptide and tetrapeptide classes showed potent receptor binding and selectivity, advancing design of satiety-inducing peptide drugs for obesity.
Pierson, M E; Comstock, J M; Simmons, R D; Julien, R; Kaiser, F; Rosamond, J D · In Vitro
Alcohol-preferring mice had lower baseline nociceptin and dynorphin B in reward regions, with alcohol consumption producing additional changes in met-enkephalin levels, linking opioid/nociceptin system configuration to alcohol preference.
Ploj, K; Roman, E; Gustavsson, L; Nylander, I · Animal Study
GHB stimulated GH release partly through GH secretagogue receptor-related pathways in addition to GABA mechanisms, with additive effects when combined with GHRP in both rats and dogs.
Rigamonti, A E; Müller, E E · Animal Study
Neuropathic and inflammatory chronic pain models produced distinct regional patterns of nociceptin, dynorphin B, and met-enkephalin changes in brain pain pathways, indicating pain type-specific opioid system plasticity.
Rosén, A; Lundeberg, T; Bytner, B; Nylander, I · Animal Study
Oral estradiol supplementation in postmenopausal women modulated continuous GHRP-2-driven GH secretion, increasing IGF-1 response but altering GH pulse dynamics, revealing estrogen-GH secretagogue interactions important for clinical dosing.
Shah, N; Evans, W S; Bowers, C Y; Veldhuis, J D · RCT
Milk-derived peptides from casein and whey digestion include opioid peptides (casomorphins), antihypertensive peptides (casokinins), mineral carriers (casein phosphopeptides), and other bioactives with diverse health effects.
Shah, N P · Review
Thymosin alpha-1 plasma levels and circadian rhythms were altered in gynecologic inflammation, varying by inflammation type and normalizing with successful treatment.
Shurlygina, A; Litvinenko, G; Dergacheva, T; Trufakin, V · Cohort
Complete dopamine system failure (combined haloperidol + reserpine) produced severe gastric lesions. BPC-157 provided superior healing compared to ranitidine, atropine, and other agents while also reducing associated catalepsy.
Sikiric, P; Separovic, J; Buljat, G; Anic, T; Stancic-Rokotov, D; Mikus, D; Duplancic, B; Marovic, A; Zoricic, I; Prkacin, I; Lovric-Bencic, M; Aralica, G; Ziger, T; Perovic, D; Jelovac, N; Dodig, G; Rotkvic, I; Mise, S; Seiwerth, S; Turkovic, B; Grabarevic, Z; Petek, M; Rucman, R · Animal Study
BPC-157 showed antidepressant activity in both the Porsolt forced swim test (reduced immobility) and chronic unpredictable stress model in rats, with effects comparable to established antidepressants.
Sikiric, P; Separovic, J; Buljat, G; Anic, T; Stancic-Rokotov, D; Mikus, D; Marovic, A; Prkacin, I; Duplancic, B; Zoricic, I; Aralica, G; Lovric-Bencic, M; Ziger, T; Perovic, D; Rotkvic, I; Mise, S; Hanzevacki, M; Hahn, V; Seiwerth, S; Turkovic, B; Grabarevic, Z; Petek, M; Rucman, R · Animal Study
Adenosine was identified as a partial agonist of the GH secretagogue receptor (GHS-R) from hypothalamic extract fractionation, producing submaximal receptor activation compared to full agonists like ghrelin.
Smith, R G; Griffin, P R; Xu, Y; Smith, A G; Liu, K; Calacay, J; Feighner, S D; Pong, C; Leong, D; Pomés, A; Cheng, K; Van der Ploeg, L H; Howard, A D; Schaeffer, J; Leonard, R J · In Vitro
Atrial standstill produced a distinctive natriuretic peptide pattern: normal-to-low ANP (from non-functional atria) with markedly elevated BNP (from stressed ventricles), providing a potential diagnostic biomarker signature.
Suguta, M; Hara, K; Nakano, A; Amano, A; Hasegawa, A; Kurabayashi, M · Case Report
ICV and intrathecal anti-dynorphin antibodies blocked immobilization stress-induced analgesia, while anti-enkephalin and anti-endorphin antibodies did not, establishing dynorphin as the specific mediator at both brain and spinal levels.
Suh, H W; Song, D K; Huh, S O; Kim, Y H · Animal Study
The pharmacological uniqueness of opiates implied endogenous opioid ligands must exist, leading to the discovery of enkephalins, beta-endorphin, and dynorphins — a family of peptides with diverse roles in pain, mood, and behavior.
Terenius, L · Review
Valsartan (angiotensin II type 1 receptor blocker) reduced TNF-α, IL-6, soluble ICAM-1, and BNP in heart failure patients, demonstrating anti-inflammatory effects of angiotensin blockade beyond hemodynamic improvements.
Tsutamoto, T; Wada, A; Maeda, K; Mabuchi, N; Hayashi, M; Tsutsui, T; Ohnishi, M; Sawaki, M; Fujii, M; Matsumoto, T; Kinoshita, M · RCT
Adenosine and multiple analogs demonstrated agonist activity at the GH secretagogue receptor (GHS-R), establishing a novel link between cellular energy metabolism and growth hormone regulation.
Tullin, S; Hansen, B S; Ankersen, M; Møller, J; Von Cappelen, K A; Thim, L · In Vitro