Introduction of ß-d-mannuronic acid (M2000) as a novel NSAID with immunosuppressive property based on COX-1/COX-2 activity and gene expression.

BACKGROUND: The NSAIDs which inhibit the cyclooxygenase (COX) enzymes are among medications widely used to treat pain and inflammation. These drugs cause digestive complications resulting in inhibition of the COX-1 enzyme, while the inhibition of the COX-2 enzyme has therapeutic effects. Therefore research focuses on the production of medications that specifically inhibit the COX-2 enzyme. This study aimed to study the effects of ß-d-mannuronic (M2000) acid on the gene expression and activity of COX-1/COX-2 enzymes in order to introduce a novel NSAID for treating inflammatory diseases. METHODS: The mRNA expression levels of COXs were analyzed with qRT-PCR. Prostaglandin E2 (PGE2) concentration in culture media was determined using ELISA method. RESULTS: Our results indicated that the M2000 at low and high dose could significantly reduce the gene expression level of COX-2 compared to the LPS group (p<0.0001), but no significant reduction was observed in the gene expression level of COX-1 compared to the LPS group. Moreover, it was noticed that this drug strongly and significantly reduced the activity of COX-1/COX-2 enzymes at the three concentrations of 5, 50 and 500 mMol/ml compared to the LPS and arachidonic acid groups (p<0.0001). CONCLUSIONS: This study showed that drug M2000 as a novel NSAID with immunosuppressive property is able strongly to inhibit the activity of COX-1/COX-2 enzymes, with suppressing the gene expression of COX-2 specifically. Therefore, based on gene expression findings this drug might be categorized and introduced as a novel NSAID with selective COX-2 inhibitory effect.

Antimicrobial susceptibility and molecular characteristics of methicillin-resistant Staphylococcus aureus in a Japanese secondary care facility.

Methicillin-resistant Staphylococcus aureus (MRSA) is prevalent in Japan, and the Staphylococcus cassette chromosome mec (SCCmec) type II is common among hospital-acquired MRSA isolates. Information pertaining to MRSA characteristics is limited, including SCCmec types, in primary or secondary care facilities. A total of 128 MRSA isolates (90 skin and soft tissue isolates and 38 blood isolates) were collected at a secondary care facility, Kawatana Medical Center, from 2005 to 2011. Antimicrobial susceptibility testing for anti-MRSA antibiotics and molecular testing for SCCmec and virulence genes (tst, sec, etb, lukS/F-PV) were performed. Strains positive for lukS/F-PV were analyzed by multilocus sequence typing and phage open-reading frame typing. SCCmec typing in skin and soft tissue isolates revealed that 65.6% had type IV, 22.2% had type II, 8.9% had type I, and 3.3% had type III. In blood isolates, 50.0% had type IV, 47.4% had type II, and 2.6% had type III. Minimum inhibitory concentrations, MIC(50)/MIC(90), against vancomycin, teicoplanin, linezolid, and arbekacin increased slightly in SCCmec II isolates from skin and soft tissue. MICs against daptomycin were similar between sites of isolation. SCCmec type II isolates possess tst and sec genes at a greater frequently than SCCmec type IV isolates. Four lukS/F-PV-positive isolates were divided into two clonal patterns and USA300 was not included. In conclusion, SCCmec type IV was dominant in blood, skin, and soft tissue isolates in a secondary care facility in Japan. Because antimicrobial susceptibility varies with the SCCmec type, SCCmec typing of clinical isolates should be monitored in primary or secondary care facilities.

[Autoantibody against the presynaptic P/Q-type voltage-gated calcium channel in Lambert-Eaton myasthenic syndrome].

Antibodies against the muscle acetylcholine receptor (AChR) were recognized as the cause of myasthenia gravis in the 1970s'. Since then, other neurological disorders associated with autoantibodies have been identified, each associated with an antibody against a ligand- or voltage-gated ion channel. Autoantibodies against P/Q-type voltage-gated calcium channels (VGCCs) are detected in patients with Lambert-Eaton myasthenic syndrome (LEMS). These antibodies interfere with the calcium-dependent release of acetylcholine from the presynaptic membrane. LEMS is an autoimmune disorder affecting the neuromuscular junction, and is characterized by proximal muscle weakness, reduction of tendon reflex, and autonomic dysfunction. Electrophysiological examinations show small-amplitude compound muscle action potentials and increments on rapid repetitive nerve stimulation. Fifty to sixty percent of LEMS patients present with tumors, mostly small cell lung carcinoma (SCLC), as a paraneoplastic syndrome. SCLC is a neuroendocrine tumor, which expresses neuronal VGCCs. Some patients present cerebellar ataxia, which is always accompanied by SCLC. These patients tend to show higher titers of VGCC antibodies than that by LEMS patients with no ataxia. The diagnosis can be confirmed by finding reduced compound muscle action potential amplitudes at rest that shows increments greater than 100% with repetitive nerve stimulation and antibody detection by using radioimmunoprecipitation assays. The treatment options are generally categorized as anti-tumor, immunomodulating, immunosuppressing, and symptomatic treatments. In cases with SCLC, effective treatment against the tumor can improve LEMS. Plasmapheresis and intravenous administration of high-dose immunoglobulins have a short effect. Prednisone, alone or in combination with immunosuppressants can achieve long-term control of the disorder.

Effect of dietary fatty acid composition on Th1/Th2 polarization in lymphocytes.

BACKGROUND: It has become increasingly clear that polyunsaturated fatty acids (PUFAs) have immunomodulatory effects. However, the intake of these fatty acids used in animal studies often greatly exceeds dietary human intake. Whether differences in the composition of fatty acids that are consumed in amounts consistent with normal dietary intake can influence immune function remains uncertain. METHODS: We manufactured 3 types of liquid diet, related to modified fatty acid composition (omega-6/omega-3 = 0.25, 2.27 and 42.9), but excluding eicosapentaenoic acid and docosahexaenoic acid, based upon a liquid diet used clinically in humans. We assessed CD3-stimulated cytokine production of splenocytes in female BALB/c mice (n = 4 per group) fed 1 of 3 liquid diets for 4 weeks. We also measured the cytokine production of peripheral blood mononuclear cells stimulated with phorbol myristate acetate and ionomycin in humans at the end of a 4-week period of consumption of 2 different liquid diets (omega-6/omega-3 = 3 and 44). RESULTS: We found that the ratio of interfero omega-gamma (IFN-gamma) / interleukin-4 (IL-4) was significantly higher in mice fed the omega-3 rich diet than in others. In humans, IFN-gamma / IL-4 was significantly higher after the omega-3 versus the omega-6 enhanced diet. CONCLUSIONS: Differences in the composition of omega-3 and omega-6 PUFAs induces a shift in the Th1/Th2 balance in both mouse and human lymphocytes, even when ingested in normal dietary amounts. An omega-3 rich diet containing alpha-linolenic acid modulates immune function.