Flavocoxid is as effective as naproxen for managing the signs and symptoms of osteoarthritis of the knee in humans: a short-term randomized,double-blind pilot study

Flavocoxid (Limbrel), a proprietary mixture of flavonoid molecules (baicalin and catechin), was tested against a traditional nonsteroidal anti-inflammatory drug, naproxen, for the management of the signs and symptoms of moderate osteoarthritis (OA) in humans. Discomfort and global disease activity were used as the primary end points, and safety assessments were also taken for both treatments as a secondary endpoint. In this double-blind study, 103 subjects were randomly assigned to receive either flavocoxid [500 mg twice daily (BID)] or naproxen (500 mg BID) in a 1-month onset of action trial. Outcome measures included the short Western Ontario and McMaster University Osteoarthritis Index, subject Visual Analogue Scale for discomfort and global response, and investigator Visual Analogue Scale for global response and fecal occult blood. Both flavocoxid and naproxen showed significant reduction in the signs and symptoms of knee OA (P ≤ .001). There were no statistically detectable differences between the flavocoxid and naproxen groups with respect to any of the outcome variables. Similarly, there were no statistically detectable differences between the groups with respect to any adverse event, although there was a trend toward a higher incidence of edema and nonspecific musculoskeletal discomfort in the naproxen group. In this short-term pilot study, flavocoxid was as effective as naproxen in controlling the signs and symptoms of OA of the knee and would present a safe and effective option for those individuals on traditional nonsteroidal anti-inflammatory drugs or cyclooxygenase-2 inhibitors. A low incidence of adverse events was reported for both groups.     

Cyclic tensile stretch load and oxidized low density lipoprotein synergistically induce lectin-like oxidized ldl receptor-1 in cultured bovine chondrocytes, resulting in decreased cell viability and proteoglycan synthesis.

Mechanical stimulation is known to be an essential factor in the regulation of cartilage metabolism. We tested the hypothesis that expression of lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) can be modulated by cyclic tensile stretch load in chondrocytes. Cyclic loading of repeated stretch stress at 10 cycles per minute with 10 kPa of stress for 6 h induced expression of LOX-1 to 2.6 times control in cultured bovine articular chondrocytes, equivalent to the addition of 10 microg/mL oxidized low density lipoprotein (ox-LDL) (2.4 times control). Application of the cyclic load to the chondrocytes along with 10 microg/mL ox-LDL resulted in synergistically increased LOX-1 expression to 6.3 times control. Individual application of cyclic loading and 10 microg/mL ox-LDL significantly suppressed chondrocytes viability (84.6% +/- 3.4% and 80.9% +/- 3.2% of control at 24 h, respectively; n = 3; p < 0.05) and proteoglycan synthesis [81.0% +/- 7.1% and 85.7% +/- 5.2% of control at 24 h, respectively; p < 0.05 when compared with 94.6% +/- 4.6% for native-LDL (n = 3)]. Cyclic loading and 10 microg/mL ox-LDL synergistically affected cell viability and proteoglycan synthesis, which were significantly suppressed to 45.6% +/- 4.9% and 48.7% +/- 6.7% of control at 24 h, respectively (n = 3; p < 0.01 when compared with individual application of cyclic loading or 10 microg/mL ox-LDL). In this study, we demonstrated synergistic effects of cyclic tensile stretch load and ox-LDL on cell viability and proteoglycan synthesis in chondrocytes, which may be mediated through enhanced expression of LOX-1 and which has important implications in the progression of cartilage degeneration in osteoarthritis.     

Molecular targets of dietary polyphenols with anti-inflammatory properties

There is persuasive epidemiological and experimental evidence that dietary polyphenols have anti-inflammatory activity. Aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) have long been used to combat inflammation. Recently, cyclooxygenase (COX) inhibitors have been developed and recommended for treatment of rheumatoid arthritis (RA) and osteoarthritis (OA). However, two COX inhibitors have been withdrawn from the market due to unexpected side effects. Because conventional therapeutic and surgical approaches have not been able to fully control the incidence and outcome of many inflammatory diseases, there is an urgent need to find safer compounds and to develop mechanism-based approaches for the management of these diseases. Polyphenols are found in many dietary plant products, including fruits, vegetables, beverages, herbs, and spices. Several of these compounds have been found to inhibit the inflammation process as well as tumorigenesis in experimental animals; they can also exhibit potent biological properties. In addition, epidemiological studies have indicated that populations who consume foods rich in specific polyphenols have lower incidences of inflammatory disease. This paper provides an overview of the research approaches that can be used to unravel the biology and health effects of polyphenols. Polyphenols have diverse biological effects, however, this review will focus on some of the pivotal molecular targets that directly affect the inflammation process.     

Microenvironment and tumor cell plasticity: An easy way out

Cancer cells undergo genetic changes allowing their adaptation to environmental changes, thereby obtaining an advantage during the long metastatic route, disseminated of several changes in the surrounding environment. In particular, plasticity in cell motility, mainly due to epigenetic regulation of cancer cells by environmental insults, engage adaptive strategies aimed essentially to survive in hostile milieu, thereby escaping adverse sites. This review is focused on tumor microenvironment as a collection of structural and cellular elements promoting plasticity and adaptive programs. We analyze the role of extracellular matrix stiffness, hypoxia, nutrient deprivation, acidity, as well as different cell populations of tumor microenvironment.     

LOX与HIF-1α在非小细胞肺癌中表达增强

目的 研究赖氨酰氧化酶(LOX)与低氧诱导因子-1α(HIF-1α)在非小细胞肺癌(NSCLC)中表达情况及其临床意义.方法 收集临床NSCLC组织标本41例,用免疫组织化学染色法(IHC)检测NSCLC组织中LOX和HIF-1α蛋白表达;蛋白印迹法(Western blot)检测NSCLC组织及相应的癌旁组织、正常肺组织中LOX与HIF-1 α蛋白表达.结果 IHC结果显示LOX蛋白表达主要在细胞质,HIF-1α蛋白表达主要在细胞核.LOX与HIF-1 α在NSCLC组织中阳性表达率均明显高于正常肺组织(P ＜0.05);LOX蛋白的高表达与肿瘤的病理类型、分化程度、淋巴转移和临床分期之间存在显著相关(P ＜0.05);HIF-1α蛋白的高表达与肿瘤的病理类型、大小、淋巴转移和临床分期之间存在显著相关(P ＜0.05);LOX与HIF-1α蛋白在NSCLC组织中表达呈正相关性(P＜0.05).Western blot结果显示NSCLC组织中LOX与HIF-1α蛋白的表达显著高于相应的癌旁组织及正常肺组织(P＜0.05).结论 LOX与HIF-1α的异常表达可能与NSCLC发生、发展有关,并且LOX与HIF-1α的高表达可能协同促进了NSCLC的侵袭转移.     

Association of Lysyl oxidase (LOX) Polymorphisms with the Risk of Keratoconus in an Iranian Population

Background: Keratoconus is a connective tissue-related eye disease with unknown etiology that causes the loss of visual acuity. Lysyl oxidase (LOX) is an amine oxidase that catalyzes the covalent cross-link of collagens and elastin in the extracellular environment, thus determining the mechanical properties of connective tissue. The current study aimed to investigate the possible associations between two LOX polymorphisms, rs1800449 and rs2288393, and susceptibility to keratoconus.

Methods: A total of 262 Iranian subjects including 112 patients with keratoconus and 150 healthy individuals as controls were recruited. Genotyping for the LOX variants was performed using allele-specific PCR.

Results: A significant difference was found between two groups regarding allelic and genotyping distribution of LOX polymorphism at position rs1800449 G>A. The frequency of AA and GA?+?AA genotypes were increased in patients compared to controls (17% versus 8% and 62.5% versus 50%, respectively), showing a statistically significant difference (OR?=?2.827, 95% CI: 1.251–6.391, p?=?0.012). The A allele was associated with an increased risk for keratoconus, with the frequency of 39.9% and 29% in patients and controls, respectively (OR?=?1.614, 95% CI: 1.119–2.326, p?=?0.011). Furthermore, the haplotype analysis revealed that the rs1800449G/rs2288393C is a protective factor against keratoconus (OR?=?0.425, 95% CI?=?0.296–0.609, p?=?0.001). Conversely, the +473A/rs2288393C (OR?=?3.703, 95% CI?=?2.230–6.149, p?=?0.001) and +473G/rs2288393G (OR?=?15.48, 95% CI?=?3.805–63.03, p?=?0.001) haplotypes were identified as risk factors for keratoconus.

Conclusion: Our study demonstrated that the LOX rs1800449 genotypes (AA and GA?+?AA) and allele (A) appears to confer risk for susceptibility to keratoconus.     

Assessing 12(S)-lipoxygenase inhibitory activity using colorectal cancer cells overexpressing the enzyme.

12(S)-Lipoxygenase (LOX) is regarded as a pro-tumorigenic enzyme and as a potential target for therapy and prevention of cancer so that the search for specific 12(S)-LOX inhibitors is part of drug development strategies. To facilitate the identification of specific 12(S)-LOX inhibitors we have created an assay cell line by introducing a12(S)-LOX expression vector into SW480 colorectal cancer cells. When arachidonic acid was supplied in the medium both transiently and stably overexpressing cells produced 12(S)-hydroxytetraenic acid (HETE) originating from the transfected gene at 4-5-fold the amount obtained from control transfectants. 12(S)-HETE production was 1913.7+/-17.2pg/ml and reached a steady state level 24h after addition of arachidonic acid. To demonstrate the models suitability of 12(S)-LOX overexpressing SW480 cells they were used to measure the inhibitory activity of the plant phenols baicalein, kaempferol, quercetin, nordihydroguaretic acid and resveratrol which are known for their chemopreventive as well as LOX-inhibitory activity in different tumour models. All 5 compounds inhibited 12(S)-HETE production at concentrations below those necessary for growth inhibition.     

Lysyl oxidase G473A polymorphism is closely associated with susceptibility to gastric cancer in a South Korean population

Yoon JH, Park JK, Kang YH, Park YK, Nam SW, Lee JY, Park WS. Lysyl oxidase G473A polymorphism is closely associated with susceptibility to gastric cancer in a South Korean population. APMIS 2011; 119: 762–8. The aim of this study was to determine whether a single nucleotide polymorphism at G473A (rs1800449) within the LOX‐propeptide is associated with susceptibility to gastric cancer. We investigated the genotype and allele frequencies of this gene in tissue specimens from 458 gastric cancer patients and 282 healthy individuals. Polymorphism analysis was performed by amplifying the propeptide region of LOX and digestion with NotI followed by sequencing of the products. The frequencies of the LOX G473A G/G, G/A, and A/A genotypes were 54.4% (249/458), 34.3% (157/458), and 11.3% (52/458), respectively, in gastric cancer patients and 58.9% (166/300), 35.5% (100/282), and 5.7% (16/282), respectively, in the healthy controls. Statistically significant differences in the genotype and allele frequency of LOX rs1800449 were observed between the healthy controls and gastric cancer patients (p = 0.0294 and p = 0.0339). When the data were stratified according to gastric cancer histologic subtype, the risk of diffuse‐type gastric cancer in carriers with an A allele (G/A or A/A genotypes) was statistically higher compared to that of carriers with the G/G genotype (p = 0.0001). Our findings suggest that G473A polymorphism of the LOX gene may be closely associated with susceptibility to the development and differentiation of gastric cancer in South Korean patients.