1.Isolation of the opioid peptide Leu-Val-Val-hemorphin-7 from bronchoalveolar lavage fluid of a patient with non-small cell lung cancer.
Duethman D;Dewan N;Conlon JM Peptides. 2000 Jan;21(1):137-42.
The decapeptide Leu-Val-Val-Tyr-Pro-Trp-Thr-Gln-Arg-Phe was isolated in high yield (1.5 nmol/ml) from bronchoalveolar lavage (BAL) fluid from a patient with an adenocarcinoma of the lung. This peptide, termed LVV-hemorphin-7 represents residues 32-41 of the beta-chain of hemoglobin and has been shown to be an endogenous ligand for opioid receptors. The N-terminal flanking peptide of LVV-hemorphin-7 [residues (1-31) of hemoglobin beta-chain] was also isolated in high yield. Neither peptide was detected in BAL fluid from the tumor-free lung of the same patient or from patients with non-neoplastic inflammatory lung disease. LVV-hemorphin-7 was not identified in BAL fluid from seven additional patients with non-small cell lung cancer, indicating that the formation of the peptide is unlikely to be of any diagnostic significance. However, the ability of LVV-hemorphin-7 to inhibit angiotensin-converting enzyme suggests that its formation may be of pathophysiological significance in the regulation of tumor blood flow in certain patients.
2.Solvent effect on kinetics of appearance of haemorphins in the course of peptic hydrolysis of bovine haemoglobin.
Lignot B;Froidevaux R;Nedjar-Arroume N;Guillochon D Biotechnol Appl Biochem. 1999 Feb;29 ( Pt 1):25-30.
The effect of the composition of the solvent on the peptic hydrolysis of bovine haemoglobin was studied to improve the preparation of two opioid peptides. Peptic hydrolysis was performed for 24 h at 23 degrees C in 0.1 M sodium acetate buffer, pH 4.5. A HPLC method was reported for isolating LVV-haemorphin-7 and VV-haemorphin-7 in one step. The kinetics of appearance of haemorphins was investigated in the presence of 20% (v/v) ethanol, a stabilizing solvent of haemoglobin or urea, a denaturant agent. Ethanol improved the yield of VV-haemorphin-7, whereas urea improved the yield of the two haemorphins. Because the amounts of haemorphins observed in urea were greater than in ethanol, the denatured state of haemoglobin is more favourable to obtaining LVV-haemorphin-7 and W-haemorphin-7. The peptide bonds that give rise to haemorphins would be more accessible to the pepsin.
3.Peptic hemoglobin hydrolysis in an ultrafiltration reactor at pilot plant scale generates opioid peptides.
Zhao Q;Piot JM;Sannier F;Guillochon D Ann N Y Acad Sci. 1995 Mar 31;750:452-8.
Two hemorphins, peptides with opioid activity, have been isolated from a pepsin hydrolysate of bovine hemoglobin, by use of gel permeation (GP) and reverse phase (RP) high-performance liquid chromatography (HPLC). Their primary structure and accurate molecular weights, determined by amino acid analysis and fast atom bombardment (FAB) mass spectrometry, were identical to fragments 31-40 (LVV-hemorphin-7) and 32-40 (VV-hemorphin 7) of the beta-chain of bovine hemoglobin. Two other peptides, 34-40 (hemorphin-7) and 34-41 (hemorphin-8) of the beta-chain of bovine hemoglobin, have been synthesized and studied. The opioid potency of these peptides, exhibited by the use of electrically stimulated muscle of isolated guinea pig ileum (GPI), were significant and comparable with some others previously described. Studies of opioid activities and primary structure of hemorphins led us to postulate the important role of arginine and phenylalanine in opioid potency.