Flavanols from Japanese quince (Chaenomeles japonica) fruit inhibit human prostate and breast cancer cell line invasiveness and cause favorable changes in Bax/Bcl-2 mRNA ratio.

Polyphenols are natural compounds of high structural diversity which translates into a very wide spectrum of biological activities, including chemoprevention. Here we report that a Japanese quince fruit flavanol preparation (JQFFP) caused favorable changes in Bax/Bcl-2 mRNA ratio, which rendered normal and cancer cells more resistant and more sensitive, respectively, to apoptosis. DU145 human prostate cancer cells were characterized by the most advantageous Bax/Bcl-2 ratio. The growth and invasiveness of MDA-MB-231 human breast cancer cells were strongly suppressed by JQFFP, which was accompanied with a decrease in MMP-9 activity and stimulation of TIMP-1 expression. Importantly, JQFFP did not decrease normal human prostate PNT1A cell number, whereas Bax/Bcl-2 ratio decreased which implies increased resistance to apoptosis. In conclusion, JQFFP exhibited a potent antiproliferative effect against cancer cells, inhibited their invasiveness, and decreased expression level of several genes involved in apoptosis, angiogenesis, and metastasis.

Procyanidins from evening primrose (Oenothera paradoxa) defatted seeds inhibit invasiveness of breast cancer cells and modulate the expression of selected genes involved in angiogenesis, metastasis, and apoptosis.

There is a growing interest in plant polyphenols (including flavanols) that exhibit pleiotropic biological activities such as antiinflammatory, antioxidant, and anticancer effects. Here, we report for the first time the inhibition of MDA-MB-231 breast cancer cell viability and invasiveness by an evening primrose flavanol preparation (EPFP). We observed a decrease in MDA-MB-231 viability of 50% vs. a control after 72 h of incubation with EPFP at a concentration of 58 µM gallic acid equivalents (GAE) and an inhibition of their invasiveness of 65% vs. a control at 75 µM GAE after 48 h of incubation. EPFP caused a 10-fold reduction in matrix metalloproteinase-9 (MMP-9) activity at 100 µM GAE. Furthermore, through modulation of mRNA expression, EPFP reduced the expression levels of the following proteins: antiapoptotic Bcl-2, angiogenic vascular endothelial growth factor (VEGF), and 2 transcription factors (c-Jun, c-Fos). Moreover, analysis by flow cytometry revealed that EPFP induced apoptosis in MDA-MB-231 cells. In conclusion, our data shows that EPFP inhibits cell viability by increasing apoptosis and decreases cell invasiveness by decreasing angiogenesis.

Melatonin augments expression of the procollagen α1 (I) and α1 (III) genes in the infarcted heart scar of pinealectomized rats.

The pineal gland is involved in the regulation of collagen accumulation in peripheral wounds and scars of the infarcted heart. This study is aimed to provide an explanation of whether the pineal gland and melatonin (MLT) is involved in the regulation of α1 (I) and α1 (III) procollagen gene expression. A secondary aim is the investigation of whether the mechanism of changes could be explained by the direct influence of MLT on myofibroblasts isolated from the scar. Myocardial infarction was induced by left coronary artery ligation in all rats. Animals were divided into groups: control, vehicle-treated rats, those injected with MLT, sham-operated animals, pinealectomized (Px) rats, and Px rats injected with vehicle or treated with MLT. In the second part of the study, cells from the scar of the infarcted heart were isolated and cultured with MLT at concentrations of 10⁻7 and 10⁻9 M. Both α1 (I) and α1 (III) procollagen gene expressions were evaluated by reverse transcription-polymerase chain reaction. Neither MLT given to intact animals nor pinealectomy alone have an influence on procollagen gene expression. However, administration of MLT to the Px animals increased the expression of α1 (I) and α1 (III) procollagen genes. Cells isolated from the heart scar were identified as myofibroblasts. MLT did not influence collagen gene expression in cultured myofibroblasts. The results indicate that MLT has an influence on procollagen gene expression in Px animals. Because the pineal product does not have an influence on the myofibroblast of the scar, the indirect mechanism of MLT action is suggested. This study may have practical implications in patients with a low level of MLT (elderly subjects, patients treated with ß-adrenergic blockers).

Procyanidin oligomers from Japanese quince (Chaenomeles japonica) fruit inhibit activity of MMP-2 and MMP-9 metalloproteinases.

The influence of procyanidin extract from Japanese quince fruit on the activities of matrix metalloproteinases MMP-2 and MMP-9 secreted to culture medium by human peripheral blood mononuclear cells (PBMC) and by human leukemia HL-60 cells was investigated by gelatin zymography. The extract proved to be an effective inhibitor of the enzymes activities (for MMP-2 and MMP-9 secreted by PBMC IC50 = 16-19 microg extract/mL and 22-25 microg extract/mL, respectively). To identify the most effective components of the extract it was fractionated by means of column chromatography on TSKgel Toyopearl HW-40 (S) bed. The obtained fractions were analyzed by TLC, HPLC, and MALDI-TOF MS. Their antioxidant activity was measured as cation radicals ABTS(.+) scavenging efficiency. The fractions VIII-XIV containing oligomers from trimer to hexamer (and probably higher oligomers) appeared to be the most effective inhibitors of MMP-2 and MMP-9 activity (IC50 value close to 4.6 microg total polyphenols/mL). To the best of our knowledge, it is the first report on gelatinase-inhibitory activity of Japanese quince fruit polyphenol extract. We conclude that polyphenols from Japanese quince can be used in cancer chemoprevention, although further studies are needed to elucidate the mechanisms underlying their biological activities.

[Type IV collagenases (MMP-2 and MMP-9) and their substrates--intracellular proteins, hormones, cytokines, chemokines and their receptors]. / Kolagenazy typu IV (MMP-2 i MMP-9) i ich substraty--bialka macierzy zewnatrzkomórkowej, hormony, cytokiny, chemokiny i ich receptory.

Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases that cleave protein components of extracellular matrix such as collagens, laminin, fibronectin, proteoglycans and contribute to cell migration by eliminating the surrounding extracellular matrix and basement membrane barriers. However, the extracellular matrix is not simply an extracellular scaffold because, for example, it contains sites that can bind growth factors; therefore, degradation of the extracellular matrix components by MMPs can alter cellular behavior. MMPs also cleave a variety of non-ECM proteins, including cytokines, chemokines, and growth factors, activating or inactivating them, or generating other products that have biological consequences. The immune system is also influenced by MMPs. For that reason, the function of MMPs is much more complex and subtle than simple demolition. MMPs are essential for embryonic development and morphogenesis, however, exuberant expression of these enzymes has been associated with a variety of destructive diseases, including tumor progression, cardiovascular diseases and autoimmune diseases.

Flavanols from evening primrose (Oenothera paradoxa) defatted seeds inhibit prostate cells invasiveness and cause changes in Bcl-2/Bax mRNA ratio.

In this study, we assessed the influence of an evening primrose flavanol preparation (EPFP) on proliferation and invasiveness of human prostate cancer cells (DU 145) and immortalized prostate epithelial cells (PNT1A). We report for the first time that EPFP reduces DU 145 cell proliferation (IC50 = 97 µM GAE for 72 h incubation) and invasiveness (by 24% versus control at 75 µM GAE). EPFP strongly inhibited PNT1A invasiveness in a concentration-dependent manner (by 67% versus control at 75 µM GAE) and did not cause a reduction in their proliferation. Furthermore, EPFP inhibited the activities of MMP-2 and MMP-9 secreted to culture medium by PNT1A cells by 84% and 34% versus control at 100 µM GAE, respectively. In the case of DU 145, MMP-9 activity at 100 µM GAE was reduced by 37% versus control. Moreover, the evening primrose seed flavanols suppressed the expression of selected genes (MMP-1, MMP-9, MMP-14, c-Fos, c-Jun, and VEGF) and also caused favorable changes in Bcl-2/Bax mRNA ratio which render DU 145 cells more sensitive to apoptosis-triggering agents. An additional confirmation of the proapoptotic activity of EPFP toward DU 145 was visualization of characteristic apoptotic bodies by DAPI staining. In conclusion, this study suggests that EPFP may increase apoptosis and reduce angiogenesis of prostate cancer cells.

Intraocular matrix metalloproteinase 2 and 9 in patients with diabetes mellitus with and without diabetic retinopathy.

INTRODUCTION: We aimed to investigate activities of metalloproteinases 2 (MMP-2) and MMP-9 in aqueous humour of patients with diabetes mellitus with various stages of diabetic retinopathy. MATERIAL AND METHODS: We included 36 samples of aqueous humour of patients suffering from diabetes mellitus, undergoing routine cataract surgery. Seven of them suffered from proliferative diabetic retinopathy (PDR), 3 had diabetic maculopathy and the remaining 26 had background or minimal background retinopathy only. Metalloproteinases 2 and MMP-9 activities in aqueous humour were measured by gelatin zymography combined with the densitometric imaging system. Total protein content in aqueous humour samples was also assessed. RESULTS: Metalloproteinases 2 activities were present in almost all samples of aqueous humour (32 of 36) and were 2.6-fold higher in patients who suffered from diabetic ocular complications (p < 0.0001). Activities of MMP-2 correlated well with the duration of the disease (correlation = 0.37, p = 0.03) and tended to correlate with total protein levels in aqueous humour (correlation = 0.43, p = 0.06). Metalloproteinases 9 activities were observed only in 2 of 7 patients with proliferative diabetic disease and the enzyme was absent from aqueous humour samples of patients without proliferative retinopathy. CONCLUSIONS: Increased activities of MMP-2 in aqueous humour of patients with PDR may be related to the disease process and support the hypothesis that MMP-2 may be of particular importance in diabetic retinal neovascularization. MMP-9 may be activated at a certain disease stage only.