Bioflavonoids effectively inhibit smooth muscle cell-mediated contraction of collagen matrix induced by angiotensin II

Paeonol Suppresses Vasculogenesis Through Regulating Vascular Smooth Muscle Phenotypic Switching

OBJECTIVE

Smooth muscle cell (SMC) phenotypic switching is associated with development of a variety of occlusive vascular diseases. Paeonol has been reported to be involved in suppressing SMC proliferation. However, it is still unknown whether paeonol can regulate SMC phenotypic switching, and which eventually result in suppressing vasculogenesis.

METHODS

Murine left common carotid artery was injured by completely ligation, and paeonol was administrated by intraperitoneal injection. Hematoxylin and eosin (H&E) staining was performed to visualize vascular neointima formation. Rat aortic SMCs were used to determine whether paeonol suppresses cell proliferation and migration. And murine hind limb ischemia model was performed to confirm the function role of paeonol in suppressing vasculogenesis.

RESULTS

Complete ligation of murine common carotid artery successfully induced neointima formation. Paeonol treatment dramatically reduced the size of injury-induced neointima. Using rat aortic primary SMC, we identified that paeonol strongly suppressed cell proliferation, migration, and decreased extracellular matrix deposition. And paeonol treatment dramatically suppressed vasculogenesis after hind limb ischemia injury.

CONCLUSION

Paeonol could regulate SMC phenotypic switching through inhibiting proliferation and migration of SMC, which results in inhibiting ischemia-induced vasculogenesis.

At the interface of antioxidant signalling and cellular function: Key polyphenol effects

The hypothesis that dietary (poly)phenols promote well‐being by improving chronic disease‐risk biomarkers, such as endothelial dysfunction, chronic inflammation and plasma uric acid, is the subject of intense current research, involving human interventions studies, animal models and in vitro mechanistic work. The original claim that benefits were due to the direct antioxidant properties of (poly)phenols has been mostly superseded by detailed mechanistic studies on specific molecular targets. Nevertheless, many proposed mechanisms in vivo and in vitro are due to modulation of oxidative processes, often involving binding to specific proteins and effects on cell signalling. We review the molecular mechanisms for 3 actions of (poly)phenols on oxidative processes where there is evidence in vivo from human intervention or animal studies. (1) Effects of (poly) phenols on pathways of chronic inflammation leading to prevention of some of the damaging effects associated with the metabolic syndrome. (2) Interaction of (poly)phenols with endothelial cells and smooth muscle cells, leading to effects on blood pressure and endothelial dysfunction, and consequent reduction in cardiovascular disease risk. (3) The inhibition of xanthine oxidoreductase leading to modulation of intracellular superoxide and plasma uric acid, a risk factor for developing type 2 diabetes.

Novel Immortal Cell Lines Support Cellular Heterogeneity in the Human Annulus Fibrosus

Introduction

Loss of annulus fibrosus (AF) integrity predisposes to disc herniation and is associated with IVD degeneration. Successful implementation of biomedical intervention therapy requires in-depth knowledge of IVD cell biology. We recently generated unique clonal human nucleus pulposus (NP) cell lines. Recurring functional cellular phenotypes from independent donors provided pivotal evidence for cell heterogeneity in the mature human NP. In this study we aimed to generate and characterize immortal cell lines for the human AF from matched donors.

Methods

Non-degenerate healthy disc material was obtained as surplus surgical material. AF cells were immortalized by simian virus Large T antigen (SV40LTAg) and human telomerase (hTERT) expression. Early passage cells and immortalized cell clones were characterized based on marker gene expression under standardized culturing and in the presence of Transforming Growth factor β (TGFβ).

Results

The AF-specific expression signature included COL1A1, COL5A1, COL12A1, SFRP2 and was largely maintained in immortal AF cell lines. Remarkably, TGFβ induced rapid 3D sheet formation in a subgroup of AF clones. This phenotype was associated with inherent differences in Procollagen type I processing and maturation, and correlated with differential mRNA expression of Prolyl 4-hydroxylase alpha polypeptide 1 and 3 (P4HA1,3) and Lysyl oxidase (LOX) between clones and differential P4HA3 protein expression between AF cells in histological sections.

Conclusion

We report for the first time the generation of representative human AF cell lines. Gene expression profile analysis and functional comparison of AF clones revealed variation between immortalized cells and suggests phenotypic heterogeneity in the human AF. Future characterization of AF cellular (sub-)populations aims to combine identification of additional specific AF marker genes and their biological relevance. Ultimately this knowledge will contribute to clinical application of cell-based technology in IVD repair.

Bioengineering of physiologically functional intrinsically innervated human internal anal sphincter constructs

Muscle replacement for patients suffering from extensive tissue loss or dysfunction is a major objective of regenerative medicine. To achieve functional status, bioengineered muscle replacement constructs require innervation. Here we describe a method to bioengineer functionally innervated gut smooth muscle constructs using neuronal progenitor cells and smooth muscle cells isolated and cultured from intestinal tissues of adult human donors. These constructs expressed markers for contractile smooth muscle, glial cells, and mature neuronal populations. The constructs responded appropriately to physiologically relevant neurotransmitters, and neural network integration was demonstrated by responses to electrical field stimulation. The ability of enteric neuroprogenitor cells to differentiate into neuronal populations provides enormous potential for functional innervation of a variety of bioengineered muscle constructs in addition to gut. Functionally innervated muscle constructs offer a regenerative medicine-based therapeutic approach for neuromuscular replacement after trauma or degenerative disorders.

A nutrient mixture suppresses carbon tetrachloride–induced acute hepatic toxicity in ICR mice

We examined the effect of a nutrient mixture (NM) that contains lysine, proline, ascorbic acid, and green tea extract in mice treated with carbon tetrachloride (CCl4), a model of liver injury in which free radical, oxidative stress, and cytokine production are closely linked. Seven-week-old male Imprinting Control Region (ICR) mice were divided into four groups (A–D) of five animals each. Groups A and C mice were fed a regular diet for 2 weeks, whereas groups B and D mice were supplemented with 0.5% NM (w/w) during that period. Groups A and B received corn oil i.p., whereas groups C and D received CCl4 (25 μL/kg, in corn oil, i.p.). All animals were killed 24 h after CCl4 administration, serum was collected to assess liver and kidney functions, and livers and kidneys were excised for histology. Mean serum aspartate aminotransferase and alanine aminotransferase were comparable in groups A and B, increased markedly in group C, and significantly lowered in group D compared with group C. CCl4 had no significant effect on renal markers (blood urea nitrogen [BUN], creatinine, and BUN/creatinine ratio). CCl4 administration caused an intense degree of liver necrosis that was less severe in the NM fed group D. These results indicate that NM could be a useful supplement in preventing acute chemical-induced liver toxicity.

A nutrient mixture prevents acetaminophen hepatic and renal toxicity in ICR mice

Acetaminophen (APAP) overdose is often fatal, leading to fulminant hepatic and renal tubular necrosis in humans and animals. We studied the effect of a nutrient mixture (NM) containing, among other nutrients, lysine, proline, ascorbic acid, N-acetyl cysteine, and green tea extract, which has previously been demonstrated to exhibit a broad spectrum of therapeutic properties on APAP-induced hepatic and renal damage in ICR (Imprinting Control Region) mice. Seven-week-old male ICR mice were divided into four groups (A–D) of five animals each. Groups A and C mice were fed a regular diet for 2 weeks, while groups B and D mice were supplemented with 0.5% NM (w/w) during that period. Groups A and B received saline i.p., while groups C and D received APAP (600 mg/kg) i.p. All animals were killed 24 h after APAP administration, serum was collected to assess the liver and kidney functions, and the livers and kidneys were excised for histology. Mean serum aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, BUN (Blood Urea Nitrogen), creatinine, and BUN/creatinine ratios were comparable in groups A and B, increased markedly in group C and significantly lower in group D compared with group C. APAP caused significant centrilobular necrosis and glomerular damage in unsupplemented animals, while NM prevented these alterations. The results indicate that NM has potential to protect against APAP-induced liver and kidney damage.