Avocado/soybean Unsaponifiables Research Articles

Inhibition of cyclooxygenase-2 expression and prostaglandin E 2 production in chondrocytes by avocado soybean unsaponifiables and epigallocatechin gallate

To evaluate the anti-inflammatory effect of the combination of avocado soybean unsaponifiables (ASU) and epigallocatechin gallate (EGCG) on cyclooxygenase-2 (COX-2) expression and prostaglandin E(2) (PGE(2)) production in cytokine-activated equine chondrocytes. Production of type II collagen and aggrecan was verified by immunohistochemistry and Western blot. Chondrocytes were incubated with: (1) control media alone, (2) ASU (4 microg/ml; 8.3 microg/ml), (3) EGCG (4, 40, 400 ng/ml), or (4) the combination of ASU and EGCG for 24h. Cells were next incubated with control medium alone or with IL-1beta (10 ng/ml) and TNF-alpha (1 ng/ml). COX-2 gene expression by real-time PCR analysis and NF-kappaB nuclear translocation by immunohistochemistry were performed after 1h of incubation. PGE(2) production was determined by immunoassay after 24h of incubation. Equine chondrocytes responded to cytokine activation by up-regulated gene expression of COX-2 and increased PGE(2) production. Activation was associated with NF-kappaB translocation. Individually, ASU and EGCG marginally inhibited COX-2 expression and PGE(2) production in activated chondrocytes. In contrast, the combination of ASU and EGCG reduced COX-2 expression close to non-activated control levels and significantly inhibited PGE(2) production. These reductions were statistically greater than those of ASU or EGCG alone. The inhibition of COX-2 expression and PGE(2) production was associated with inhibition of NF-kappaB translocation. The present study demonstrates that the anti-inflammatory activity of ASU and EGCG is potentiated when used in combination. This combination may offer an attractive supplement or alternative to non-steroidal anti-inflammatory drugs (NSAIDs) in the management of osteoarthritis.

Avocado soybean unsaponifiables (ASU) suppress TNF-α, IL-1β, COX-2, iNOS gene expression, and prostaglandin E 2 and nitric oxide production in articular chondrocytes and monocyte/macrophages

To evaluate the effects of avocado soybean unsaponifiables (ASU) on proinflammatory mediators in chondrocytes and monocyte/macrophage-like cells. To determine the dose response of ASU, chondrocytes (5 x 10(5) cells/well) were incubated at 5% CO(2), 37 degrees C for 72 h with (1) control media alone or (2) ASU at concentrations of 0.3, 0.9, 2.7, 8.3, and 25 microg/ml. Cells were activated with 20 ng/ml lipopolysaccharide (LPS) for 24 h and cell supernatants were analyzed for prostaglandin E(2) (PGE(2)) and nitrite content. Chondrocytes and THP-1 monocyte/macrophages (5 x 10(5) cells/well) were incubated at 5% CO(2), 37 degrees C for 72 h with (1) control media alone or (2) ASU (25 mug/ml). One set of cells was activated for 1 h with LPS (20 ng/ml) for both reverse-transcriptase PCR and real-time PCR analysis of tumor necrosis factor-alpha (TNF-alpha), interleukin-1-beta (IL-1beta), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) expression. One set of cells was activated for 24 h to analyze secreted PGE(2) and nitrite levels in the cellular supernatant. ASU reduced TNF-alpha, IL-1beta, COX-2, and iNOS expression in LPS-activated chondrocytes to levels similar to nonactivated control levels. The suppression of COX-2 and iNOS expression was paralleled by a significant reduction in PGE(2) and nitrite, respectively, in the cellular supernatant. ASU also reduced TNF-alpha and IL-1beta expression in LPS-activated monocyte/macrophage-like cells. The present study demonstrates that the anti-inflammatory activity of ASU is not restricted to chondrocytes, but also affects monocyte/macrophage-like cells that serve as a prototype for macrophages in the synovial membrane. These observations provide a scientific rationale for the pain-reducing and anti-inflammatory effects of ASU observed in osteoarthritis patients.

Stress-induced signaling pathways in hyalin chondrocytes: inhibition by Avocado–Soybean Unsaponifiables (ASU)

Avocado-Soybean Unsaponifiables (ASU) represent one of the most commonly used drugs for symptomatic osteoarthritis (OA). The mechanisms of its activities are still poorly understood. We investigate here the effects of ASU on signaling pathways in mouse or human chondrocytes. Mouse or human chondrocytes stimulated with interleukin-1beta (IL1beta, 10 ng/ml) and cartilage submitted to a compressive mechanical stress (MS) were studied in the presence or absence of ASU (10 microg/ml). Nuclear factor kappaB (NF-kappaB) activation was assessed by immunoblot, using an I-kappa B alpha antibody, nuclear translocation of NF-kappaB using p65 antibody, and extra-cellular signal-regulated kinase (ERK)1/2 activation using phospho and ERK1/2 antibodies. The binding of the p50/p65 complex on DNA was studied by electrophoretic mobility shift assay. ASU decrease matrix metalloproteinases-3 and -13 expressions and Prostaglandin E(2) (PGE(2)) release in our model. The degradation of I-kappa B alpha is prevented in the presence of ASU as shown by the persistent expression of I-kappa B alpha protein in the cytosol when chondrocytes are stimulated by IL1beta or MS. Nuclear translocation of the NF-kappaB complex is shown by the decrease of the p65 protein from the cytosol, whereas p65 appears in the nucleus under IL1beta stimulation. This translocation is abolished in the presence of ASU. Moreover, bandshift experiments show an inhibition of the IL1beta-induced binding of p50/p65 complexes to NF-kappaB responsive elements in response to ASU. Finally, among the different mitogen-activated protein kinases known to be induced by IL1beta, ERK1/2 was the sole kinase inhibited by ASU. These results demonstrate that ASU express a unique range of activities, which could counteract deleterious processes involved in OA, such as inflammation.

Oral Administration of Avocado Soybean Unsaponifiables (ASU) Reduces Ischemic Damage in the Rat Hippocampus

The beneficial effects of avocado/soybean unsaponifiables (ASU) are known as an antiarthritic agent. This experimental study presents the effects of ASU on oxidant/antioxidant systems and the number of apoptotic neurons of hippocampal formation after ischemia and reperfusion. Eighteen rats were divided into three equal groups: group I rats were used as controls; group II rats were fed with standard diet and group III rats were fed with standard diet plus ASU pills for 10 days. One day after electrocauterization of bilateral vertebral arteries for groups II and III, bilateral common carotid arteries were occluded for 30 min and then reperfused for 30 min. After these procedures, rats of all groups were sacrificed. The levels of malondialdehyde (MDA) and nitric oxide (NO) and activities of superoxide dismutase (SOD) and catalase (CAT) were measured in the left hippocampus. The number of apoptotic neurons was counted by Tunel method in histological samples of right hippocampus. MDA and NO levels increased in group II compared with group I rats (p = 0.002, p = 0.015). In group III, MDA and NO levels decreased as compared to group II (p = 0.041, p = 0.002). SOD and CAT activities increased in group III as compared to group II rats (p = 0.002, p = 0.002). The number of apoptotic neurons was lower in group III as compared to group II rats. The present findings suggest that ASU could decrease oxidative stress and apoptotic changes in ischemic rat hippocampus. Dietary supplementation of ASU may be beneficial to prevent or ameliorate ischemic cerebral vascular disease.

The utility of nutraceuticals in the treatment of osteoarthritis

Osteoarthritis (OA) treatment is limited by the inability of prescribed medications to alter disease outcome. As a result, patients with OA often take food substances called nutraceuticals in an attempt to affect the structural changes that occur within a degenerating joint. The role of nutraceuticals in OA management can be defined only by an evidence-based approach to support their use. This paper reviews the clinical trials studying glucosamine, chondroitin sulfate, vitamin C, vitamin E, and avocado-soybean unsaponifiables. It highlights the need for additional randomized, placebo-controlled trials to further define the utility of nutraceuticals in OA treatment.

Inhibition of Pro‐inflammatory Gene Expression in Chondrocytes, Monocytes, and Fibroblasts by the Combination of Avocado Soybean Unsaponifiables, Glucosamine, and Chondroitin Sulfate

Recent studies have shown the benefit of the natural products: avocado soybean unsaponifiables (ASU), glucosamine (Glu), and chondroitin sulfate (CS) in alleviating pain and inflammation. Their mechanism of action is not fully understood. We tested the hypothesis that the combination of ASU, Glu, and CS down-regulates pro-inflammatory gene expression. Equine and human chondrocytes, human fibroblasts, or human monocyte/macrophage surrogate THP-1 cells were incubated for 24 hrs with: control media alone, ASU (8.3 μg/ml), Glu (11 μg/ml) and CS (20 μg/ml), or combination of ASU (8.3 μg/ml NMX1000™-ASU), Glu (11 μg/ml), and CS (20 μg/ml). Cells were activated for 1 hr with lipopolysaccharide (20 ng/ml) or IL-1β (10 ng/ml). RT-PCR analysis showed that the combination product suppressed COX-2 and chemokine (IL-8, MCP) expression in chondrocytes and fibroblasts. The combination product also suppressed cytokines (TNF-α, IL-1β) and iNOS expression in THP-1 cells. The anti-inflammatory effect of the combination product was more profound than the individual agents alone in THP-1 cells. Our study supports the potential clinical utility of the combination of ASU, Glu, and CS in suppressing inflammation. This combination product may provide an alternative treatment to patients who fail to respond to the single agents alone. Supported by Nutramax Laboratories, Inc. and Mississippi State University.

Osteoarthritis and nutrition. From nutraceuticals to functional foods: a systematic review of the scientific evidence

The scientific and medical community remains skeptical regarding the efficacy of nutrition for osteoarthritis despite their broad acceptation by patients. In this context, this paper systematically reviews human clinical trials evaluating the effects of nutritional compounds on osteoarthritis. We searched the Medline, Embase, and Biosis databases from their inception to September 2005 using the terms random, double-blind method, trial, study, placebo, and osteoarthritis. We selected all peer-reviewed articles reporting the results of randomised human clinical trials (RCTs) in osteoarthritis that investigated the effects of oral interventions based on natural molecules. Studies on glucosamine and chondroitin sulfate were excluded. The quality of the RCTs was assessed with an osteoarthritic-specific standardised set of 12 criteria and a validated instrument. A best-evidence synthesis was used to categorise the scientific evidence behind each nutritional compound as good, moderate, or limited. A summary of the most relevant in vitro and animal studies is used to shed light on the potential mechanisms of action. Inclusion criteria were met by 53 RCTs out of the 2,026 identified studies. Good evidence was found for avocado soybean unsaponifiables. Moderate evidence was found for methylsulfonylmethane and SKI306X, a cocktail of plant extracts. Limited evidence was found for the Chinese plant extract Duhuo Jisheng Wan, cetyl myristoleate, lipids from green-lipped mussels, and plant extracts from Harpagophytum procumbens. Overall, scientific evidence exists for some specific nutritional interventions to provide symptom relief to osteoarthritic patients. It remains to be investigated whether nutritional compounds can have structure-modifying effects.

Osteoarthritis: Pharmacology and clinical indications of selected botanicals

Knowledge concerning phyto-anti-inflammatory drugs (PAIDs) has increased tremendously during recent years. A number of high quality studies indicate that some proprietary herbal medicinal products from Harpagophytum procumbens and Salix species should be considered as alternatives for the treatment of osteoarthritis or low back pain due to the lower incidence of severe adverse events and lower cost compared to synthetic analgesics. For others, for example, products from Urtica dioica or Ribes nigrum, the resinous gum of Boswellia serrata and ginger, the clinical evidence of effectiveness needs to be demonstrated and for the avocado-soybean unsaponifiables the confirmatory study failed to show effectiveness.

Symptoms modifying effect of avocado/soybean unsaponifiables (ASU) in knee osteoarthritis

Objectives: We compare the symptomatic effects of 300 or 600 mg daily of ASU in patients with knee osteoarthritis. Methods: A multicenter, double blind, study comparing a daily intake of 300 mg or 600 mg of ASU and placebo. The study lasted 3 months and involved patients of both genders, aged 45 to 80 years and presenting with femoro-tibial knee osteoarthritis. The primary endpoint was NSAIDs and analgesics intake between D30 and D90. Results: All efficacy parameters were significantly improved (p< 0.01), in the two ASU groups compared to the placebo group. At D90, NSAIDs and analgesics intake decreased by more than 50% in 71% of the patients receiving ASU 300 mg or 600 mg, compared to 36% of the patients receiving placebo. From D0 to D90 Lequesne's index dropped by 3.9 and 2.9 points in ASU 300 mg and 600 mg groups, respectively, against 1.6 in those receiving placebo. Conclusion: The efficacy of ASU at a dosage of 300 mg/day and 600 mg/day was consistently superior to that of placebo at all endpoints, with no differences observed between the two doses.

Herbal therapy for treating osteoarthritis.

The increasing popularity of complementary and alternative medicine appears to be particularly evident amongst people with chronic disease. In the treatment of osteoarthritis, one therapy that has been identified as having potential benefit, is herbal medicine (phytotherapy). To determine the effectiveness of herbal therapies in treating osteoarthritis. Databases for mainstream and complementary medicine were searched using terms to include all forms of arthritis combined with herbal medicine. We searched the following electronic databases: MEDLINE, EMBASE, CISCOM, AMED, CINAHL, Cochrane Controlled Trials Register (CCTR), Cochrane Musculoskeletal specialized register, Dissertation Abstracts, BIDS ISI and the Cochrane Complementary Medicine Fields Specialized Register. We also searched the reference lists from retrieved trials. All randomized trials of herbal interventions in osteoarthritis, compared to placebo. Studies were included according to the a priori protocol and agreement between two reviewers who independently read each selected paper for content and for assessment of quality. Papers of any language were included. Data were extracted independently by the same two reviewers. Five studies (four different herbal interventions) met the review criteria. Two studies were suitable for data pooling. It was not possible to draw firm conclusions from the single studies but two studies of avocado/soybean unsaponifiables showed beneficial effects on functional index, pain, intake of NSAIDs and global evaluation. No serious side effects were reported. The evidence for avocado-soybean unsaponifiables in the treatment of osteoarthritis is convincing but evidence for the other herbal interventions is insufficient to either recommend or discourage their use.