Relation between collagen synthesis and collagen proline hydroxylase activity in mammalian cells

In silico Study of Trianthema portulacastrum Embedded Iron Oxide Nanoparticles on Glycogen Synthase Kinase-3β: A Possible Contributor to its Enhanced in vivo Wound Healing Potential

Rich amount of phenolic compounds are available in Trianthema portulacastrum L. (TP) leaves and are traditionally utilized as a wound dressing material. Oxidative stress and inflammation affect the Wnt/β-catenin pathway by modulating the glycogen synthase kinase-3β (GSK) activity subjected to delay in wound healing. The objective of the current study was to explore the wound healing effect of ferric oxide nanoparticles biosynthesized with fractionated TP extract (FeTP). The ability of TP active components (polyphenols) to inhibit the GSK was explored by using molecular docking studies. FeTP were synthesized, characterized, utilized to prepare an ointment and its efficacy was investigated against full-thickness dermal wounds. Different wound healing parameters, level of enzymatic antioxidants, hydroxyproline content and tissue cytokines level were analyzed. Histopathology was performed to confirm the healing by newly formed tissue architecture. Rats treated with FeTP showed significantly swift healing with faster wound contraction rate, high tensile strength and hydroxyproline content along with the utilization of less time for epithelialization. Histopathological study also validated the potential wound healing effect of FeTP with complete re-epithelialization. The results of the present study cumulatively revealed that the green synthesized FeTP ointment approach may serve as a potential tool for dermal wound healing.

The Collagen Suprafamily: From Biosynthesis to Advanced Biomaterial Development

Collagen is the oldest and most abundant extracellular matrix protein that has found many applications in food, cosmetic, pharmaceutical, and biomedical industries. First, an overview of the family of collagens and their respective structures, conformation, and biosynthesis is provided. The advances and shortfalls of various collagen preparations (e.g., mammalian/marine extracted collagen, cell-produced collagens, recombinant collagens, and collagen-like peptides) and crosslinking technologies (e.g., chemical, physical, and biological) are then critically discussed. Subsequently, an array of structural, thermal, mechanical, biochemical, and biological assays is examined, which are developed to analyze and characterize collagenous structures. Lastly, a comprehensive review is provided on how advances in engineering, chemistry, and biology have enabled the development of bioactive, 3D structures (e.g., tissue grafts, biomaterials, cell-assembled tissue equivalents) that closely imitate native supramolecular assemblies and have the capacity to deliver in a localized and sustained manner viable cell populations and/or bioactive/therapeutic molecules. Clearly, collagens have a long history in both evolution and biotechnology and continue to offer both challenges and exciting opportunities in regenerative medicine as nature's biomaterial of choice.

Ameliorative effect of biofabricated ZnO nanoparticles of Trianthema portulacastrum Linn. on dermal wounds via removal of oxidative stress and inflammation

An impediment in the process of wound healing can be attributed to reactive oxygen species and inflammation. The curative efficacy of green synthesized Trianthema portulacastrum Linn. zinc oxide nanoparticles (ZnOTP) was investigated in the present study for evaluation of their wound healing potential in rodents. Total phenolic and flavonoid content of ZnOTP was determined, and antioxidant potential was evaluated by the DPPH method. In vitro anti-inflammatory activity of ZnOTP was evaluated by membrane stabilization and albumin denaturation, along with proteinase inhibitory assays. The synthesized ZnOTP were characterized by UV-Visible spectroscopy, Fourier transform infrared (FT-IR) studies, Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-ray (EDX) studies. The wound healing potential of ZnOTP was monitored by excision and incision wound models. Analyses confirmed the formation of spherical nanoparticles of 10-20 nm size along with strong signals of zinc and oxygen atoms. Significant results (p < 0.05) of wound contraction rate, epithelialization and histopathology of the healed tissues of rats confirmed the promising wound healing property of ZnOTP. In addition, inflammatory markers, biochemical estimation such as the hydroxyproline content of granulation tissue, and the profile of antioxidant enzymes also supported the wound healing potential of ZnOTP. The present study advocated the attenuation of wounds via antioxidant and anti-inflammatory activities of a green synthesized nano-ointment.

Evaluation of Cynodon dactylon for wound healing activity

BACKGROUND AND AIMS

Research in the field of wound healing is very recent. The concept of wound healing is changing from day to day. Ayurveda is the richest source of plant drugs for management of wounds and Cynodon dactylon L. is one such. The plant is used as hemostatic and wound healing agent from ethnopharmacological point of view. Aim of the present study is scientific validation of the plant for wound healing activity in detail.

MATERIALS AND METHODS

Aqueous extract of the plant was prepared and phytochemical constituents were detected by HPLC analysis. Acute and dermatological toxicity study of the extract was performed. Pharmacological testing of 15% ointment (w/w) of the extract with respect to placebo control and standard comparator framycetin were done on full thickness punch wound in Wister rats and effects were evaluated based on parameters like wound contraction size (mm²), tensile strength (g); tissue DNA, RNA, protein, hydroxyproline and histological examination. The ointment was applied on selected clinical cases of chronic and complicated wounds and efficacy was evaluated on basis of scoring on granulation, epithelialization, vascularity as well as routine hematological investigations.

RESULTS

Significant results (p<0.05) were observed both in pharmacological and clinical studies.

CONCLUSION

The present research with aqueous extract of Cynodon dactylon explores its potential wound healing activity in animal model and subsequent feasibility in human subjects. Phenolic acids and flavonoids present in c. dactylon supports its wound healing property for its anti-oxidative activity that are responsible for collagenesis.

Sodium-dependent vitamin C transporter isoforms in skin: Distribution, kinetics, and effect of UVB-induced oxidative stress

Two sodium-dependent vitamin C transporter isoforms (SVCT1 and SVCT2) were identified as ascorbic acid transporters, but their roles in skin have, as yet, not been elucidated. Here we analyze the expression and function of SVCTs in healthy human skin cells and skin tissues, and in UVB-induced cutaneous tissue injury. SVCT1 was primarily found in the epidermis expressed by keratinocytes, whereas SVCT2 expression was in the epidermis and dermis in keratinocytes, fibroblasts, and endothelial cells. Uptake experiments revealed that ascorbic acid affinity of SVCT1 was lower than SVCT2 (K(m)=75 muM and K(m)=44 muM, respectively), but maximal velocity was 9-times higher (36 nmol/min/well). In keratinocytes, SVCT1 was found to be responsible for vitamin C transport, although SVCT2 gene expression was higher. On UVB irradiation, SVCT1 mRNA expression in murine skin declined significantly in a time- and dose-dependent manner, whereas SVCT2 mRNA levels were unchanged. Furthermore, UVB irradiation of keratinocytes in vitro was accompanied by reduced ascorbic acid transport. In summary, these data indicate that the two vitamin C transporter isoforms fulfill specific functions in skin: SVCT1 is responsible for epidermal ascorbic acid supply, whereas SVCT2 mainly facilitates ascorbic acid transport in the dermal compartment. UVB-induced oxidative stress in mice resulted in depletion of SVCT1 mRNA levels and led to significantly decreased ascorbic acid uptake in keratinocytes, providing evidence on why ascorbic acid levels are decreased on UVB irradiation in vivo.

Colorectal anastomotic healing and intracolonic bypass procedure

Intestinal anastomoses continue to be complicated by leakages even in the best of hands despite the development of new surgical techniques, suture materials, devices, and stapling instruments. One may explain such persistence of anastomotic leakage on the basis of the dynamic effect that multiple factors have on the healing of an anastomosis. Awareness of these factors and proper precautions by the surgeon can make a high-risk anastomosis less prone to leakage. The intracolonic bypass procedure is an alternative to a temporary colostomy. It does not prevent an anastomotic dehiscence but can prevent anastomotic leakage with its associated complications in those situations where dehiscence is most likely to occur.

Relationship between Progesterone Receptor and Productive Fibrosis as an Index of Tumor Differentiation in Breast Cancer

We studied the relationship between steroid receptors (SR) and various stromal parameters in 100 breast cancers. Each specimen was submitted to SR determination by the dextran-coated charcoal assay and to histologic examination. No relationship was found between the presence of SR and necrosis or fibroblastic cell content. There was an inverse correlation between SR positivity and the extent of lymphocyte infiltration (p < 0.05). ER + PR + status was strongly correlated with marked productive fibrosis (PF) (p < 0.005). When SR were separately assayed, only the presence of PR was correlated with PF (p < 0.005); similar results were obtained for PR levels (p < 0.01). PF was also associated with a higher nuclear grade (p < 0.001). In conclusion, in this study a strong correlation between PR positivity or concentration and extent of PF was demonstrated in breast cancer. Since PR synthesis is an expression of an intact regulatory pathway, our data suggest that stromal production in breast cancer is related to the degree of differentiation of malignant epithelial cells.

Wound healing

The majority of wounds encountered in the accident and emergency department are superficial in nature and a consequence of accidental trauma or the elective surgical incision of infected foci. The techniques of management of such cases have undergone few changes in recent years, and any advances of a practical or therapeutic nature have been comparatively modest. On the other hand, many major advances have occurred in our understanding of the factors involved in the basic pathophysiology of wound repair. This paper is a summary of our present concept of the process of repair in soft tissues.

Connective tissue synthesis by cultured scleroderma fibroblasts. I. In vitro collagen synthesis by normal and scleroderma dermal fibroblasts

The authors have been unable to demonstrate an increase in collagen synthesis by fibroblasts isolated from sclerodermatous skin. In order to elucidate this problem further, scleroderma fibroblasts were biopsied from upper dermis, from lower (including subcutaneous) dermis, and from adjacent clinically noninvolved skin. All cell lines failed to show a significant increase in collagen synthesis when they were compared to control fibroblast lines. One difference among them was that fibroblasts from involved areas showed a rate of collagen synthesis equal to or less than cells isolated from adjacent clinically noninvolved sites.

The relationship between the free pool of proline and collagen content in human liver cirrhosis

The free proline, free glutamic acid, and total collagen contents of the livers of cirrhotic and noncirrhotic patients were determined. The amounts of free proline in the sera of the patients were also determined. The results indicated that certain metabolic changes occurred in cirrhotic livers of humans that were similar to the metabolic changes observed previously in CCl(4)-induced cirrhosis in the rat. The amount of free proline was coordinate with the increase in total collagen, and both were inversely related to the amount of free glutamic acid. The average proline concentration in sera of cirrhotic patients was not higher than that of non cirrhotic patients, suggesting that the metabolic alteration noted above is a local event in the liver related to fibrogenesis. These and other results suggest that the pool size of free proline may play a prime role in regulation of collagen biosynthesis in liver cirrhosis.