Study on leptin enhancing collagen systhesis in wounded rats / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To investigate the effect of leptin on collagen systhesis in wounded rats.</p><p><b>METHODS</b>Thirty male Wistar rats, weight (180 +/- 20)g, were randomly divided into three groups (n = 10) by weight: normal depilation group, wound control group and leptin treatment group and ten rats were included in each group. A full-thickness defect measuring 2 x 2.5 cm was made in the back of rats in wound control group and leptin treatment group. Each wound in rats of leptin treatment group was applied topically with 0.1 ml leptin solution (2.0 microg leptin), daily for 7 days and that of wound control group with equivalent saline solution. All rats were killed and then granulation tissues samples and skin were collected to examine the synthesis of collagen.</p><p><b>RESULTS</b>Hydroxyproline content in granulation tissues of in leptin treatment group (33.92 +/- 3.09) mg/g were significantly increased than those in control group (29.55 +/- 3.59 mg/g, P < 0.05). The mRNA expressions of collagen I and III were significantly enhanced in leptin treatment group (0.96 +/- 0.09, 0.09 +/- 0.06) than those in control group (0.80 +/- 0.03, 0.08 +/- 0.03). The levels of type I and III collagen were significantly increased in leptin treatment group than those in control group.</p><p><b>CONCLUSION</b>Leptin applied topically can accelerate wound healing through enhancing gene expression of type I and III collagen and synthesis of collagen in wound tissue.</p>

Apparatus for the measurement of the oxygen uptake of rats subjected to hypobaric hypoxia / 中国应用生理学杂志

<p><b>OBJECTIVE</b>To construct an apparatus for the oxygen uptake measurement of rats exposed to hypobaric hypoxia at different simulated altitude.</p><p><b>METHODS</b>The capacity of this apparatus was about 0.01 m3. It included animal experimental cabin, reference cabin, altimeter, altitude vertical velocity indicator, pressure difference inductor and oxygen compensator, low scale manometer, soda lime and calcium chloride, small fan, thermometer, circulating water system and vacuum pump. The oxygen uptake of the rats at 6 000 m, 4 000 m and 1 000 m simulated altitude was measured using this apparatus.</p><p><b>RESULTS</b>The oxygen uptake of the rats at 50 m, 4 000 m and 6 000 m simulated altitude was (24.4 +/- 2.1), (10.8 +/- 2.0) and (8.8 +/- 1.6) ml O2/(kg x min) respectively (average +/- s, n = 10). The oxygen uptake decreased as altitude increased.</p><p><b>CONCLUSION</b>This apparatus can be used to measure the oxygen uptake of the rats at different simulated altitude.</p>

Effects of pumpkin polysaccharides on blood glucose and blood lipids in diabetic rats / 中国应用生理学杂志

<p><b>AIM</b>To investigate the effects of pumpkin polysaccharides on blood glucose and lipids levels in diabetic rats.</p><p><b>METHODS</b>Diabetic rats induced by alloxan through intraperitoneal injection were randomly divided into three groups, diabetes, xiaoke pill and pumpkin polysaccharides group, according to weight and blood glucose level. And the normal control group was founded at the same time. The normal control group and diabetes group were lavaged with distilled water, other two groups were respectively lavaged with xiaoke pill or pumpkin polysaccharides. Weighed once a week, and analyzed fasting blood glucose, total cholesterol, triglyceride, high density lipoprotein, low density lipoprotein, and free fatty acid level in serum after 4 weeks.</p><p><b>RESULTS</b>In diabetes group, weight and high density lipoprotein level decreased, and fasting blood glucose, total cholesterol, triglyceride, low density lipoprotein, and free fatty acid level in serum increased significantly. But, all of the indexes changed oppositely in xiaoke pill group and pumpkin polysaccharides group, and effects of pumpkin polysaccharides were better.</p><p><b>CONCLUSION</b>Pumpkin polysaccharides can increase the weight, decrease the blood glucose and lipids levels in diabetic rats, and have some good effects to diabetes and diabetes complications.</p>

Effects of soybean isoflavones on the cell cycles, the cell apoptosis and the proliferation of spleen in radiated mice / 中国应用生理学杂志

<p><b>AIM</b>To study effect of soybean isoflavones (SI) on spleen in radiated mice.</p><p><b>METHODS</b>90 male mice were randomly divided into control group, radiated group, radiated plus 0.5% dose SI group. After 2-week feeding, the mice received 4.0 Gy 137Cs gamma-radiation, the cell cycles, cell apoptosis and proliferation on the spleen and the spleen index were observed in radiated after 12 h, 24 h, 1 week and 2 weeks.</p><p><b>RESULTS</b>After the mice were radiated, the spleen were significantly atrophy, the rate of the cell apoptosis and the cell cycles of G0-G1 phase in splenocytes were significantly increased (P < 0.01), the cell cycles rate of S phase and the proliferation index were significantly decreased in spleen (P < 0.05). Compared with radiated group, the spleen atrophy and the rate of the cell cycles of G0-G1 phase were significantly decreased (P < 0.05), and the cell cycles of G2-M phase and the proliferation index were significantly increased (P < 0.05) in the mice supplied 0.5% soybean isoflavones.</p><p><b>CONCLUSION</b>The soybean isoflavones could significantly increase spleen radioprotective effect in mice.</p>

Effects of genistein on bone mineralization in ovariectomized rats / 中国应用生理学杂志

<p><b>AIM</b>To investigate the effects of genistein on bone mineralization in ovariectomized rats.</p><p><b>METHODS</b>Forty-seven Wistar rats were randomly allocated into six groups: sham-operated (sham), ovariectomized (ovx), ovariectomized supplied with diethyl stilbestrol (E, 20 microg x kg bw(-1) x d(-1)) or genistein (25, 50, 100 mg x kg bw(-1) x d(-1)). After the rats had been fed for three months, analysis of the bone mineral density, parameters related to mineralization, bone content of Ca, P, Mg, Mn and Zn and serum concentration of parathyroid calcitonin and estrogen was performed.</p><p><b>RESULTS</b>Bone mineral density, bone Ca, P, Zn and Mg content and serum estrogen concentration in ovariectomized rats were significantly decreased, but mean osteoid width increased, mineralization lag time and osteoid maturation period prolonged compared with sham animals. After three months supplementation to ovariectomized rats, bone Ca, P and Mg content increased, mean osteoid width decreased, mineralization lag time and osteoid maturation period shortened compared with ovariectomized animals.</p><p><b>CONCLUSION</b>Genistein promotes bone mineralization by increasing bone Ca, P, Mg and adjusting serum calcitonin to prevent osteoporosis.</p>

Effects of genistein on proliferation and differentiation of osteoblast / 中国应用生理学杂志

<p><b>AIM</b>To study the effects of genistein on proliferation and differentiation of osteoblasts in neonatal rat calvaria cultures.</p><p><b>METHODS</b>Osteoblasts were isolated from neonatal rat calvaria through trypsin and collagenase digestion, and cultured in the presence of different doses of genistein (10(-5) mol/L, 10(-6) mol/L and 10(-7) mol/L). The proliferation and DNA and collagen synthesis of osteoblasts were assayed by MTT method and 3H-TdR and 3H-proline incorporation. The activity of ALP were measured by ALP assay kit.</p><p><b>RESULTS</b>Genistein significantly increased osteoblast 3H-TdR and 3H-proline incorporation and MTT, 10(-6) mol/L genistein increased ALP activity.</p><p><b>CONCLUSION</b>Genistein increased osteoblast DNA and collagen synthesis in neonatal rat calvaria cultures, and promoted osteoblast proliferation and differentiation.</p>