Alpha-crystallin is a member of the family of small heat-shock proteins (sHSP) and is composed of two subunits, alphaA-crystallin and alphaB-crystallin, which exhibit molecular chaperone-like properties. In a previous study, we found that residues 70-88 in alphaA-crystallin can function like a molecular chaperone by preventing the aggregation and precipitation of denaturing substrate proteins [Sharma, K. K., et al. (2000) J. Biol. Chem. 275, 3767-3771]. In this study, we show that the complementary sequence in alphaB-crystallin, residues 73-92 (DRFSVNLDVKHFSPEELKVK), is the functional chaperone site of alphaB-crystallin. Like the mini-alphaA-crystallin chaperone, the mini-alphaB-crystallin chaperone interacts with 1,1'-bi(4-anilino) naphthalene-5,5'-disulphonic acid (bis-ANS) and also possesses significant beta-sheet and random coil structure. Deletion of four residues (DRFS) from the N-terminus or deletion of C-terminus LKVK residues from the 73-92 peptide abolishes the chaperone-like activity against denaturing alcohol dehydrogenase. However, removal of DRFS or HFSPEELKVK is necessary to completely abolish the antiaggregation property of the peptide in insulin reduction assay. Substitution of Asp at a site corresponding to D80 in alphaB-crystallin with d-Asp or beta-Asp results in a significant loss of chaperone-like activity. Kynurenine modification of His in the peptide abolishes the antiaggregation property of the mini-chaperone. These data suggest that the 73-92 region in alphaB-crystallin is one of the substrate binding sites during chaperone activity.

Angiogenesis plays a crucial role in wound healing by forming new blood vessels from preexisting vessels by invading the wound clot and organizing into a microvascular network throughout the granulation tissue. This dynamic process is highly regulated by signals from both serum and the surrounding extracellular matrix environment. Vascular endothelial growth factor, angiopoietin, fibroblast growth factor and transforming growth factor-beta are among the potent angiogenic cytokines in wound angiogenesis. Specific endothelial cell ECM receptors are critical for morphogenetic changes in blood vessels during wound repair. In particular integrin (αvβ3) receptors for fibrin and fibronectin, appear to be required for wound angiogenesis: αvβ3 is focally expressed at the tips of angiogenic capillary sprouts invading the wound clot, and any functional inhibitors of αvβ3 such as monoclonal antibodies, cyclic RGD peptide antagonists, and peptidomimetics rapidly inhibit granulation tissue formation. In spite of clear knowledge about influence of many angiogenic factors on wound healing, little progress has been made in defining the source of these factors, the regulatory events involved in wound angiogenesis and in the clinical use of angiogenic stimulants to promote repair.

Oxidized betaB3-peptide interacts with betaB2-crystallin and enhances its aggregation and precipitation. Peptide-induced aggregation and increased hydrophobicity of the lens crystallin at 37 degrees C are relevant to crystallin aggregation in the aging lenses.

Inhibition of angiotensin converting enzyme(ACE) in presence of captopril(C), lisinopril(L) and enalapril(E) were investigated in testis and epididymis of sheep using Hip‐His‐Leu as substrate. Captopril, lisinopril and enalapril were competitive inhibitors of the enzyme from both tissues. Differences in the I50 and Ki values using these three inhibitors reflects the affinities of these inhibitors for the, ACE. In addition, the relative potencies of captopril, lisinopril and enalapril were different for testicular ACE(C > L > E) and epididymal ACE(L>C >E). This observation suggests differences between the active sites of the testicular and epididymal ACE which may reflect on their functions in vivo.

Background:Negative pressure wound therapy has emerged as an attractive treatment modality for the management and healing of chronic ulcers. Though numerous clinical studies are available, there is a lack of biochemical and histological studies evaluating the healing of chronic wounds.Materials and Methods:In the present study, a total 60 patients were divided into two groups: Limited access dressing (LAD) group (n = 30) and conventional dressing group (n = 30). Various biochemical parameters such as hydroxyproline, total protein and antioxidants such as reduced glutathione (GSH), glutathione peroxidase (GPx), catalase (CAT) and oxidative biomarker malondialdhyde (MDA) are measured in the granulation tissue. Histologically amount of inflammatory infiltrate, angiogenesis, and collagen deposition are studied to assess wound healing.Results:Patients treated with LAD have shown significant increase in the mean (±standard deviation) hydroxyproline (77.3 ± 30.1 vs. 32.3 ± 16.18; P = 0.026), total protein (13.89 ± 9.0 vs. 8.9 ± 4.59; P = 0.004), GSH (7.4 ± 1.91 vs. 5.1 ± 1.28; P = 0.039), GPx (122.3 ± 59.3 vs. 88.7 ± 34.11; P = 0.030), CAT (1.80 ± 1.14 vs. 0.9 ± 0.71; P = 0.002) and decrease in MDA (13.4 ± 5.5 vs. 8.6 ± 3.8; P = 0.004). Histological study showed comparatively fewer inflammatory cells, increased and well organised collagen bundles, and more angiogenesis in the LAD group when compared with that with conventional dressing after 10 days of treatment.Conclusion:In the present study, we have found beneficial effect of newer intermittent negative pressure therapy in combination with moist environment (LAD) on chronic wound healing by increasing collagen deposition and angiogenesis; and reducing oxidative stress and inflammatory infiltrate.