The effect of pea albumin 1F on glucose metabolism in mice.

Pea albumin 1F (PA1F), a plant peptide isolated from pea seeds, can dramatically increase blood glucose concentration by subcutaneous injection with a dosage of 5 or 10 microg/g (body weight) in normal and type II diabetic mice (KK/upj-Ay). The voltage-dependent anion channel 1 (VDAC-1) has been identified as the PA1F binding protein from mice pancreatic cell membrane, which may be involved in the regulation of enhancing blood glucose in response to PA1F binding. The results clearly show that peptide-signaling molecules from plants can affect mammalian physiological functions, especially, in association with glucose metabolism.

Preparation and identification of monoclonal antibodies against recombinant human thioredoxins.

Thioredoxin (Trx) is a member of the thioredoxin protein family and has a conserved catalytic domain (-Trp-Cys-Gly-Pro-Cys-Lys-) with reduction/oxidation (redox) activity. There are two main members in this family, Trx-1, a cytosolic and nuclear form, and Trx -2, a mitochondrial form. Trx-1 is a 104 amino acid multifunctional protein that has been extensively studied. Here we report the preparation of monoclonal antibodies (MAb) against recombinant human Trx-1(hTrx). To enhance its immunogenicity, Trx-1 was coupled to carrier protein bovine serum albumin by a two-step glutaraldehyde method. Using conventional procedures, we prepared three stable hybridoma cell lines that can produce and secret anti-Trx MAbs. We further analyzed their isotypes, titer, and affinity and found that those MAbs belong to the G1 subclass with kappa light chains, respectively. The MAbs were capable of recognizing hTrx-1, as determined by Western blotting.

[Value of multiplanar reconstruction of lumbar nerve roots on the same level by high resolution computed tomography in diagnosis of lumbar disc herniation and/or bulge].

OBJECTIVE: To explore value of multiplanar reconstruction of lumbar nerve roots on the same level by high resolution computed tomography (HRCT) in diagnosis of lumbar disc herniation and/or bulge (LDHB). METHODS: Thirty-one patients with manifestations of typical nerve root compression, such as lumbago and tenderness of percussion pain at the corresponding sites were scanned with 16-slice spiral CT and multiplanar reconstruction of lumbar nerve roots on the same level with the workshop ADW4.150, and were diagnosed as with LDHB with 50 segments. The diagnoses were confirmed by operation later. RESULTS: This technique showed not only the existence of LDHB but also the signs of nerve root compression, including the touch of nerve roots with the LDHB (100%), translocation of nerve roots (96%), morphological change (94%), changes of diameter (92%), changes of direction (88%), changes of density (80%), increase of the angle between the dural sac and nerve root (76%), etc. Along with the prolonging of time, the nerve roots became thinner in all segments. CONCLUSION: Multiplanar reconstruction of lumbar nerve roots on the same level by high resolution computed tomography is valuable in the diagnosis of lumbar disc herniation and/or bulge.

Activity of the plant peptide aglycin in mammalian systems.

A 37 residue peptide, aglycin, has been purified from porcine intestine. The sequence is identical to that of residues 27-63 of plant albumin 1 B precursor (PA1B, chain b) from pea seeds. Aglycin resists in vitro proteolysis by pepsin, trypsin and Glu-C protease, compatible with its intestinal occurrence and an exogenous origin from plant food. When subcutaneously injected into mice (at 10 microg.g(-1) body weight), aglycin has a hyperglycemic effect resulting in a doubling of the blood glucose level within 60 min. Using surface plasmon resonance biosensor technology, an aglycin binding protein with an apparent molecular mass of 34 kDa was detected in membrane protein extracts from porcine and mice pancreas. The polypeptide was purified by affinity chromatography and identified through peptide mass fingerprinting as the voltage-dependent anion-selective channel protein 1. The results indicate that aglycin has the potential to interfere with mammalian physiology.

Preparation and identification of monoclonal antibodies against daintain.

Daintain is a 17-kDa polypeptide originally purified from porcine intestine. This polypeptide is associated with insulin secretion and inflammatory responses. Daintain is highly similar in amino acid sequence to allograft inflammatory factor-1 (AIF-1). Here we report the preparation and identification of monoclonal antibodies (MAbs) against daintain. To enhance its immunogenicity, daintain was coupled to carrier protein bovine serum albumin (BSA) by a two-step glutaraldehyde method. Using conventional procedures, we obtained four stable hybridoma cell lines that can produce and secret anti-daintain MAbs. We further analyzed their isotypes, titer, and affinity, and found that those MAbs belong to the G1 subclass with kappa light chains. The MAbs were capable of recognizing daintain as determined by Western blotting. The produced MAbs will be a useful tool for further investigation of daintain functions in organisms.

Preparation and identification of monoclonal antibodies against pea albumin 1b (PA 1b).

PA 1b (pea albumin 1b), extracted from pea seeds, is thermostable and is multifunctional. It has an attractive peros toxicity, and is also involved in the regulation of callus growth and cell proliferation. Here we report the preparation of monoclonal antibodies (MAbs) against this peptide for further investigation of peptide distribution and functions. PA 1b was coupled to carrier protein using the two-step glutaraldehyde method as an immunal antigen. Five stable cell lines producing anti-PA 1b MAbs were obtained. We analyzed their isotypes, titer, and affinity and found that those MAbs belong to the G(1) and G(2b) subclasses with kappa light chain, respectively. Using these antibodies, a competitive inhibition ELISA was developed, and approximately 15 nmol/L of antigen was detected.