Inflammation, insulin resistance and traditional chinese medicine treatment of diabetes mellitus / 中国药学杂志

Low grade inflammation has recently emerged as a common underlying cause of many chronic diseases. Heart disease, type 2 diabetes, Alzheimer's disease and many types of cancer have all been associated with chronic inflammation. Diabetes is a group of metabolic diseases characterized by hyperglycemia resulting from defects in insulin secretion, insulin action, or both. Insulin resistance is a key component in the development of diabetes mellitus which is caused by inflammation, and throughout the whole process of diabetes. In recent years, research on traditional Chinese medicine treatment of diabetes has got lots of achievements, and makes a further analysis about insulin resistance of diabetic, while has profound significance in the treatment of diabetes in the future. Insulin resistance can be improved with Chinese herb medicine using compound, single herbal drug and its extracts. This review focuses on the pathogenesis of inflammation and insulin resistance, and the effects of Chinese herb medicine on insulin resistance in diabetes.

A new bibenzyl compound from Dendrobium nobile / 药学学报

In this study, seven bibenzyl compounds were isolated from the stem of Dendrobium nobile by silica gel, MCI column chromatographic and preparative HPLC technology. By using spectroscopic techniques including NMR and MS, these compounds were identified as 4, α-dihydroxy-3, 5, 3'-trimethoxybibenzyl (1), 4, 5-dihydroxy-3, 3', α-trimethoxybibenzyl (2), 4, 4'-dihydroxy-3, 5, 3'-trimethoxybibenzyl (3), 4, 5-dihydroxy-3, 3'-dimethoxybibenzyl (4), 4, 3'-dihydroxy-3, 5-dimethoxybibenzyl (5), 5, 4'-dihydroxy-3, 3'-dimethoxybibenzyl (6) and 5, 3'-dihydroxy-3-methoxybibenzyl (7). Compound 1 is a new compound and compound 4 was isolated from this plant for the first time.

Establishment of a cell model of insulin-resistant 3T3-L1 adipocytes / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the optimal conditions for establishing insulin-resistant 3T3-L1 adipocytes.</p><p><b>METHOS</b>Dexamethason (DEX), 3-isobutyl-methylxanthine (IBMX) and different concentrations of insulin (10(-8), 10(-7), and 10(-6) mol·L(-1)) were used to induce 3T3-L1 preadipocytes into mature adipocytes identified by oil red O staining. We established insulin- resistant 3T3-L1 adipocytes cell model (IR-3T3-L1) by exposing the cells to 1µmol·L(-1) DEX, and the changes of glucose concen- tration in the cell culture were determined by glucose oxidase-peroxidase (GOD-POD) assay.</p><p><b>RESULTS</b>Treatment of 3T3-L1 cells with DEX, IBMX and 10(-6) mol·L(-1)) insulin for 9 days resulted in the differentiation of >90% of the cells into mature adipocytes. IR-3T3-L1 cells cultured for 96 h in the culture media containing 1 µmol·L(-1) DEX showed significantly increased glucose consumption (P=0.0003) as compared with the control group at 36 h (P<0.001).</p><p><b>CONCLUSION</b>3T3-L1 cells can be induced into mature adipocytes by exposure to 1 µmol·L(-1) DEX, 0.5 mmol·L(-1) IBMX and 10(-6) mol·L(-1)) insulin. A 96 h exposure to 1 µmol·L(-1) DEX can induce 3T3-L1 adipocytes to acquire insulin resistance that can be maintained for 36 h.</p>

Effects of rutaecarpine on inflammatory cytokines in insulin resistant primary skeletal muscle cells / 中国中药杂志

It is now well established that inflammation plays an important role in the development of numerous chronic metabolic diseases including insulin resistance (IR) and type 2 diabetes (T2DM). Skeletal muscle is responsible for 75% of total insulin-dependent glucose uptake; consequently, skeletal muscle IR is considered to be the primary defect of systemic IR development. Our pre- vious study has shown that rutaecarpine (Rut) can benefit blood lipid profile, mitigate inflammation, and improve kidney, liver, pan- creas pathology status of T2DM rats. However, the effects of Rut on inflammatory cytokines in the development of IR-skeletal muscle cells have not been studied. Thus, our objective was to investigate effects of Rut on inflammatory cytokines interleukiri (IL)-1, IL-6 and tumor necrosis factor (TNF)-α in insulin resistant primary skeletal muscle cells (IR-PSMC). Primary cultures of skeletal muscle cells were prepared from 5 neonate SD rats, and the primary rat skeletal muscle cells were identified by cell morphology, effect of ru- taecarpine on cell proliferation by MTT assay. IR-PSMC cells were induced by palmitic acid (PA), the glucose concentration was measured by glucose oxidase and peroxidase (GOD-POD) method. The effects of Rut on inflammatory cytokines IL-1, IL-6 and TNF-α in IR-PSMC cells were tested by enzyme-linked immunosorbent assay (ELISA) kit. The results show that the primary skeletal muscle cells from neonatal rat cultured for 2-4 days, parallel alignment regularly, and cultured for 7 days, cells fused and myotube formed. It was shown that Rut in concentration 0-180. 0 μmol x L(-1) possessed no cytotoxic effect towards cultured primary skeletal muscle cells. However, after 24 h exposure to 0.6 mmol x L(-1) PA, primary skeletal muscle cells were able to induce a state of insulin resistance. The results obtained indicated significant decrease (P < 0.05 to P < 0.001) IL-1, IL-6 and TNF-α production by cultured IR-PSMC cells when incubating 24 hours with Rut, beginning from 20 to 180.0 μmol x L(-1). IL-1, IL-6 and TNF-α in the Rut treated groups were dose-dependently decreased compared with that in the IR-PSMC control group. Our results demonstrated that the Rut promoted glucose consumption and improved insulin resistance possibly through suppression of inflammatory cytokines in the IR-PSMC cells.

Effects of four kinds of Chinese medicine monomer on growth of PANC-1 xenograft tumor and studying of molecular mechanism / 中国中药杂志

<p><b>OBJECTIVE</b>The antitumor effects of icarisid II, timosaponin A-III, neferine and salidroside were studied in PANC-1 xenograft tumor.</p><p><b>METHOD</b>To establish of the nude mice xenograft tumor model, PANC-1 cells were injected. When the tumor major diameter was reached 3-5 mm, the treatment was initiated. The mice were randomized into vehicle control and treatment groups of six animals per each. Chinese medicine monomer was injected intraperitoneally every day. In 23th day, mice were killed once a day, tumor tissue were isolated and weighed and divided into two parts. One part was fixed with formaldehyde for tissue section and immunohistochemistry, the another of tissue was frozen in liquid nitrogen then in - 80 degrees C refrigerator for gene and protein expression analysis.</p><p><b>RESULT</b>In PANC-1 tumor xenograft experiment, compared with model group, timosaponin A-III (1.0 mg x kg (-1)) exerted significant inhibitory effects on tumor growth. Timosaponin A-III suppressed mRNA expressions of VEGF (P < 0.05), reduced protein expressions of VEGF (P < 0.05), activated Caspase-3 protein. Icarisid II, neferine and salidroside had not an excelled antitumor effect.</p><p><b>CONCLUSION</b>Timosaponin A-III exerted an excelled antitumor effect. The antitumor mechanisms include anti-angiogenesis, apoptosis promotion.</p>