Curcumin improves wound healing by modulating collagen and decreasing reactive oxygen species

Wound healing consists of an orderly progression of events that re-establish the integrity of the damaged tissue. Several natural products have been shown to accelerate the healing process. The present investigation was undertaken to determine the role of curcumin on changes in collagen characteristics and antioxidant property during cutaneous wound healing in rats. Full-thickness excision wounds were made on the back of rat and curcumin was administered topically. The wound tissues removed on 4th, 8th and 12th day (post-wound) were used to analyse biochemical and pathological changes. Curcumin increased cellular proliferation and collagen synthesis at the wound site, as evidenced by increase in DNA, total protein and type III collagen content of wound tissues. Curcumin treated wounds were found to heal much faster as indicated by improved rates of epithelialisation, wound contraction and increased tensile strength which were also confirmed by histopathological examinations. Curcumin treatment was shown to decrease the levels of lipid peroxides (LPs), while the levels of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), activities were significantly increased exhibiting the antioxidant properties of curcumin in accelerating wound healing. Better maturation and cross linking of collagen were observed in the curcumin treated rats, by increased stability of acid-soluble collagen, aldehyde content, shrinkage temperature and tensile strength. The results clearly substantiate the beneficial effects of the topical application of curcumin in the acceleration of wound healing and its antioxidant effect. Both the authors have contributed equally towards this paper.     

Fibrinogen Induces Microglia-Mediated Spine Elimination and Cognitive Impairment in an Alzheimer’s Disease Model

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Prognostic factors in canine appendicular osteosarcoma - a meta-analysis

ABSTRACT: BACKGROUND: Appendicular osteosarcoma is the most common malignant primary canine bone tumor. When treated by amputation or tumor removal alone, median survival times (MST) do not exceed 5 months, with the majority of dogs suffering from metastatic disease. This period can be extended with adequate local intervention and adjuvant chemotherapy, which has become common practice. Several prognostic factors have been reported in many different studies, e.g. age, breed, weight, sex, neuter status, location of tumor, serum alkaline phosphatase (SALP), bone alkaline phosphatase (BALP), infection, percentage of bone length affected, histological grade or histological subtype of tumor. Most of these factors are, however, only reported as confounding factors in larger studies. Insight in truly significant prognostic factors at time of diagnosis may contribute to tailoring adjuvant therapy for individual dogs suffering from osteosarcoma.The objective of this study was to systematically review the prognostic factors that are described for canine appendicular osteosarcoma and validate their scientific importance. RESULTS: A literature review was performed on selected studies and eligible data were extracted. Meta-analyses were done for two of the three selected possible prognostic factors (SALP and location), looking at both survival time (ST) and disease free interval (DFI). The third factor (age) was studied in a qualitative manner. Both elevated SALP level and the (proximal) humerus as location of the primary tumor are significant negative prognostic factors for both ST and DFI in dogs with appendicular osteosarcoma. Increasing age was associated with shorter ST and DFI, however, was not statistically significant because information of this factor was available in only a limited number of papers. CONCLUSIONS: Elevated SALP and proximal humeral location are significant negative prognosticators for canine osteosarcoma.     

Design of Escherichia coli-Expressed Stalk Domain Immunogens of H1N1 Hemagglutinin That Protect Mice from Lethal Challenge

The hemagglutinin protein (HA) on the surface of influenza virus is essential for viral entry into the host cells. The HA1 subunit of HA is also the primary target for neutralizing antibodies. The HA2 subunit is less exposed on the virion surface and more conserved than HA1. We have previously designed an HA2-based immunogen derived from the sequence of the H3N2 A/HK/68 virus. In the present study, we report the design of an HA2-based immunogen from the H1N1 subtype (PR/8/34). This immunogen (H1HA0HA6) and its circular permutant (H1HA6) were well folded and provided complete protection against homologous viral challenge. Antisera of immunized mice showed cross-reactivity with HA proteins of different strains and subtypes. Although no neutralization was observable in a conventional neutralization assay, sera of immunized guinea pigs competed with a broadly neutralizing antibody, CR6261, for binding to recombinant Viet/04 HA protein, suggesting that CR6261-like antibodies were elicited by the immunogens. Stem domain immunogens from a seasonal H1N1 strain (A/NC/20/99) and a recent pandemic strain (A/Cal/07/09) provided cross-protection against A/PR/8/34 viral challenge. HA2-containing stem domain immunogens therefore have the potential to provide subtype-specific protection.     

Alteration in haematocrit values and plasma protein fractions during the breeding cycle of female pigeons, Columba livia

Haematocrit measurements and plasma protein electrophoresis were carried out in female pigeons (Columba livia) during the breeding cycle. Non-laying birds showed higher (p < 0.001) haematocrit values than those involved in courtship and mating, nest-building, incubation and feeding and brooding. Significant differences in relative percentage of various plasma protein fractions were observed as a function of breeding. Haematocrit could be a useful index to the non-laying status of pigeons like that in chickens, Gallus domesticus.     

Studies on the induction of -aminolevulinic acid synthetase iun mouse liver

Administration of 3,5-diethoxy carbonyl-1,4-dihydrocollidine (DDC) to mice resulted in a striking increase in the level of δ-aminolevulinic acid (ALA) synthetase in liver. Although the enzyme activity was primarily localized in mitochondria and postmicrosomal supernatant fluid, a significant level of activity was also detected in purified nuclei. The time course of induction showed a close parallelism between the bound and free enzyme activities with the former always accounting for a higher percentage of the total activity as compared to the latter. Studies with cycloheximide indicated a half-life of around 3 hr for both the bound and free ALA synthetase. Actinomycin D and hemin prevented enzyme induction when administered along with DDC, but when administered 12 hr after DDC treatment Actinomycin D did not lead to a decay of either the bound or free enzyme activity and hemin inhibited the bound enzyme activity but not the free enzyme level. The molecular sizes of the mitochondrial and cytosolic ALA synthetase(s) were found to be similar on sephadex columns.     

Vitamin E prevents deleterious effects of di (2-ethyl hexyl) phthalate, a plasticizer used in PVC blood storage bags

Vitamin E administration prevented DEHP induced deleterious effects like (i) degenerative changes in the brain and thyroid, (ii) decrease in the activity of neuronal membrane Na+ - K+ ATPase, (iii) decrease in the concentration of insulin, cortisol and TSH, and (iv) the increase in T3 and T4 in female Albino rats. The results suggest use of vitamin E to prevent harmful effects of repeated transfusion of DEHP containing blood as in thalassemia patient. The possibility of using vitamin E to prevent the harmful effects of repeated transfusion of DEHP containing blood, as in thalassemia patients, is discussed.     

Molecular docking analysis of beta-caryophyllene with IRS-1, cSrc and Akt

Diabetes mellitus (DM) is a common metabolic illness defined by hyperglycemia caused by insufficient production or absent of pancreatic insulin, with or without concomitant insulin action impairment. Hence, novel problem-solving approaches for assessing early metabolic diseases, notably insulin resistance, are urgently needed. Screening of natural compounds for drug discovery to combat diabetes is common in modern medical research and development. Therefore, it is of interest to document the molecular docking analysis data of beta-Caryophyllene, a naturally occurring sequiterpene with the downstream insulin signaling molecules such as IRS-1, cSrc and Akt for the management of type-2 diabetes. The molecular docking analysis data of beta-caryophyllene with the insulin downstream signaling molecules such as IRS-1, cSrc and Akt reveals its ability and further studies are needed to elucidate its complete mechanism of action against type-2 diabetes.     

Development of a microplate-based scintillation proximity assay for MraY using a modified substrate

MraY is an established target for the discovery of antibacterial agents. The conventional assay for MraY uses radioactive substrate and analysis of products after paper chromatography or butanol extraction. Synthesis of radiolabeled substrate has been done in vitro using purified enzymes or by growing cells on radiolabeled precursors. The authors report a simple and rapid method to chemically radiolabel MraY substrate, UDP-MurNAc-pentapeptide. Specific activity obtained by this method was more than 100 times higher than the conventionally labeled substrate, and yields are high enough to support the requirements of high-throughput screening (HTS). The authors have developed a microplate-based homogeneous assay for MraY in which the product is captured on wheat germ agglutinin (WGA) scintillation proximity assay (SPA) beads. The assay was validated by showing inhibition by specific inhibitors of MraY but not by inhibitors of other enzymes of peptidoglycan synthesis. The assay uses wild-type membranes of Escherichia coli, giving it an advantage over recently described assays that need the protein to be overexpressed. In addition, it has an advantage over the high-throughput MraY-MurG coupled assay reported in the literature because it is MraY specific, and therefore hits obtained in this assay do not need further deconvolution. It has potential for use in HTS approaches to find novel inhibitors of MraY.