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1.
This study was done to determine the long-term effect of D-003 on bones of ovariectomized (ovx) rats distrib-uted in 4 groups: a false-operated and three groups of ovx rats: one treated with the vehicle and two with D-003 (5 and 250 mg/kg). D-003 significantly prevented, in a dose-dependent fashion, the trabecular bone volume (TBV), trabecular number (TbN) and trabecular thickness (TbTh) reduction induced in ovx rats and the increase of trabecular separation (TbSp) osteoclast number (OcN) and osteoclast surface (OcS/BS) increased in the positive controls versus the sham group. It is concluded that D-003 administered for 12 months prevented bone loss and decreased bone resorption in ovx rats, without evidences of impaired bone quality.  相似文献   

2.
The mevalonate pathway is relevant in bone cells. Statins inhibit 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, the key enzyme of this route, stimulating osteoblast differentiation and activity. Pravastatin increases bone formation markers in postmenopausal women and bone density in diabetics. D-003 is a mixture of high-molecular-weight acids purified from sugarcane wax which inhibits cholesterol biosynthesis through HMG-CoA reductase regulation, preventing bone loss in osteoporosis induced with ovariectomy and prednisolone in rats. We investigated the effects of D-003 (50 mg/kg) and pravastatin (20 mg/kg) orally administered for 12 weeks to ovariectomized rats. Female rats were randomized in four groups (10 rats/group): two control groups treated with the vehicle, one false-operated (sham) and another ovariectomized (positive control), while two other groups received D-003 or pravastatin. Bone resorption and formation was studied through histomorphometry and apoptosis through immunohistochemistry. D-003 and pravastatin significantly (p < 0.001) prevented the changes of trabecular bone versus ovariectomized rats and (p < 0.001) the increase of the surface and number of osteoclasts versus ovariectomized controls. D-003 and pravastatin, however, did not modify osteoblast surfaces, a bone formation marker D-003 and pravastatin increased osteoclast apoptosis and reduced (p < 0.05) osteoblast and osteocyte apoptosis versus ovariectomized controls; D-003 was more effective (p < 0.05) than pravastatin. In conclusion, D-003 (50 mg/kg) orally administered for 12 weeks prevented bone loss and bone resorption in ovariectomized rats, increasing osteoclast apoptosis. The preventive effects of D-003 on bone loss and resorption in ovariectomized rats are comparable to those of pravastatin. Both drugs inhibited osteoblast apoptosis but failed to change osteoblast surface. The effects of D-003 on bone cell apoptosis were greater than those of pravastatin. Therefore, D-003 could be used to prevent or treat bone loss in postmenopausal women, but further animal studies and clinical trials are required to confirm the clinical relevance of this potential effect.  相似文献   

3.
Bisphosphonates inhibit bone resorption through mechanisms involving the metabolic pathway from mevalonate to cholesterol. Mevalonate is a precursor of the lipoids required for osteoclast activity and thus inhibition of its synthesis affects bone metabolism. Inhibitors of hydroxymethylglutaryl CoA (HMGCoA) reductase might increase experimentally new bone formation through a mevalonate-dependent effect. D-003 is a mixture of high molecular weight fatty acids isolated from sugar cane wax, which inhibits cholesterol biosynthesis through indirect regulation of HMGCoA reductase activity. This study was undertaken to determine whether D-003 could prevent bone loss in ovariectomized rats. Sprague Dawley female rats were ovariectomized or sham operated and were randomly distributed into five groups: a control ovariectomized and a sham (false-operated) group receiving Tween/H2O vehicle, a group treated with alendronate (3 mg/kg/day) and two groups treated with D-003 (50 and 200 mg/kg/day). Treatments were administered for 3 months. At sacrifice, bones were removed and histological variables of bone resorption and formation were studied by histomorphometry. Ovariectomy diminished trabecular number and thickness and increased trabecular gap, osteoclast number and surface. Alendronate and D-003 prevented a decrease in trabecular number and thickness as well as increases in trabecular separation, osteoclast number and surface compared with ovariectomized controls, thus preventing the bone loss and decreased bone resorption induced by ovariectomy, but failed to increase osteoblast surface compared with control ovariectomized rats. In conclusion, D-003 (50 and 200 mg/kg/day) prevented bone loss and decreased bone resorption in ovariectomized rats, which suggests that this substance could be promising in preventing or treating osteoporosis.  相似文献   

4.
Biphosphonates, which are antiresorptive agents used to treat osteoporosis, inhibit the mevalonate pathway, preventing protein prenylation and inhibiting osteoclast activity. Statins decrease cholesterol biosynthesis by blocking the mevalonate pathway and have been reported to have beneficial effects on bone. D-003 is a mixture of high molecular weight acids purified from sugarcane wax that inhibits cholesterol biosynthesis before mevalonate production. D-003 prevents bone loss and resorption in rats with osteoporosis induced with ovariectomy or corticoids. Biochemical markers of bone turnover are used to monitor the short-term efficacy of antiosteoporotic therapy. This randomized, double-blind, placebo-controlled study was undertaken to investigate the short-term effects of D-003 (10 mg/day) on biochemical markers of bone turnover in postmenopausal women with low bone mineral density (BMD). After 4 weeks on a low-fat diet, 34 women were randomized to D-003 (10 mg/day) or placebo for 6 months. Pre- and post-treatment samples were analyzed for urinary excretion of deoxypyridinoline (DPD)/creatinine (Cr), a marker of bone resorption, and serum bone specific alkaline phosphatase (BSAP), a marker of bone formation. The effects on lipid profile and safety indicators, as well as adverse events (AE), were investigated. D-003 (10 mg/day) lowered urinary excretion of tDPD/Cr versus baseline (20.6%) (p < 0.001) and placebo (33.7%) (p < 0.01), but did not modify serum BSAP. D-003 decreased low-density lipoprotein-cholesterol (LDL-C) (32.8%), total cholesterol (TC) (16.4%) and the TC/high-density lipoprotein-cholesterol (HDL-C) ratio (34.7%), increased HDL-C (30.3%) (p < 0.001) and did not modify triglycerides. The effects on these variables were significant as early as 3 months after treatment initiation. D-003 was well tolerated. Three patients (one in the placebo group and two in the D-003 group) withdrew from the study. Two of these withdrawals were due to AE: abdominal pain (placebo) and heartburn (D-003). Five patients (four in the placebo group [22.2%] and one in the D-003 group [6.3%]) reported mild AE. In conclusion, D-003 (10 mg/day) reduced urinary excretion of tDPD/Cr, a bone resorption marker and did not change serum BSAP, a bone formation marker, while it lowered cholesterol in study patients. These preliminary results suggest that D-003 could be useful in treating postmenopausal women with low BMD. However, the potential value of D-003 in treating or preventing osteoporosis deserves further clinical investigation.  相似文献   

5.
Osteoporosis is a metabolic bone disease characterized by low bone mass, impaired micro-architecture and susceptibility to fracture. Osteoporosis may be, inter alia, a result of a long-term glucocorticosteroid therapy, e.g. with prednisolone. Although a number of properties of prednisolone in influencing bone metabolism have been recognized, the effect of prednisolone-induced osteoporosis on the function of blood circulation and autonomic nervous system in bones remains open. In order to clarify this problem, the present study concentrated on the effects of catecholamines on intramedullary pressure in rats with prednisolone-induced osteoporosis. Prednisolone was administered to male Wistar rats at the doses of 5 mg/kg im, for 3 weeks. Norepinephrine, epinephrine, isoprenaline as well as adrenoceptor antagonists (phentolamine and propranolol) were administered to the controls and to the rats with prednisolone-induced osteoporosis. The examinations demonstrated that rats with prednisolone-induced osteoporosis displayed a decreased intramedullary pressure. In addition, a disordered effect of catecholamines on intramedullary pressure of osteoporotic bone was observed.  相似文献   

6.
目的:观察甲状旁腺激素(PTH)间歇注射对月龄较老的去卵巢大鼠骨组织形态计量学的影响.方法:6月龄雌性SD大鼠被随机分成5组:(1)假手术基础组(ShamB),(2)去卵巢基础组(OVXB),(3)假手术终点组(ShamE),(4)去卵巢终点组(OVXE),(5)去卵巢后PTH治疗组(OVXE).ShamB和OVXB组大鼠于术后3个月、ShamE及OVXE和OVXEP组大鼠在术后4.5个月时处死并取骨.在术后3—4.5个月时给OVXE组大鼠每日皮下注射1次(6次/周)rhPTH_(1-84),给ShamE和OVXE组大鼠则注射rhPTH_(1-84)溶剂.对大鼠近端胫骨进行不脱钙切片以观察其骨组织形态计量学指标的变化.结果:OVXE组骨小梁面积百分比(TbAr)明显高于OVXE组(P<0.05),与OVXB组相似(P>0.05),但仍低于ShamE组(P<0.05);OVXE组的骨小梁厚度(TbTh)高于任何其他各组(P<0.05),其骨小梁数量(TbN)仅比OVXE组略高,其标记周长百分比(LPm)、矿化沉积率(MAR)和骨形成率(BFR/BV)均分别高于OVXE和ShamE组(P<0.01),而其破骨细胞数量(N of Oc)与后二组相似(P>0.05).结论:去卵巢后3个月的9月龄大鼠短期间歇注射rhPTH_(1-84)能阻止其骨量进一步减少,其作用机制是间歇注射PTH能增加TbTh而不明显改变TbN,能促进成骨活性而不影响破骨活性.  相似文献   

7.
Benign prostatic hyperplasia (BPH) is a nonmalignant growth of prostate leading to difficulty in urinating. Drug therapy, phytotherapy included, is frequently used to treat BPH. D-004 is a lipid extract from Roystonea regia fruits, and previous studies have shown that oral treatment with D-004 for 14 days prevented prostate hyperplasia (PH) induced by testosterone in rats. No information is available, however; about the effects of D-004 in reverting already established PH. This study investigated whether D-004 could improve PH after oral dosing with testosterone in rats. Rats were distributed in five groups (10 rats/group). One group was injected with soy oil (negative control) and four groups were injected with testosterone: one was orally treated with the vehicle (positive control), two with D-004 (200 and 400 mg/kg) and the other with Saw palmetto (400 mg/kg). At study completion, the rats were sacrificed and the prostates were removed and weighed. D-004 (200 and 400 mg/kg) significantly and dose-dependently decreased prostate enlargement by 85% and 98%, respectively, versus the positive control. Likewise, Saw palmetto (400 mg/kg) significantly reduced prostate weight by 73% versus the positive control. D-004 (400 mg/kg) was more effective (p < 0.05) than Saw palmetto (400 mg/kg) in lowering prostate enlargement. D-004 and Saw palmetto also decreased the prostate weight to body weight ratio, but did not affect body weight. In conclusion, D-004 (200 and 400 mg/kg) orally administered was effective for reducing PH after testosterone dosing. D-004 (400 mg/kg) was more effective than Saw palmetto (400 mg/kg). Further studies, however, are needed to corroborate the present results.  相似文献   

8.
D-003 is a mixture of high molecular weight aliphatic primary acids purified from sugar cane wax (Saccharum officinarum, L) with cholesterol-lowering and antiplatelet effects. Previous studies, including a 6-month study conducted in rats, have shown no D-003-related toxicity. The present study was undertaken to investigate the effects of D-003 orally administered for 9 months in beagle dogs. The animals were randomly distributed in three groups: a control group receiving the vehicle only and two groups orally administered D-003 (200 and 400 mg/kg). Body weight gain, food consumption and clinical signs were controlled throughout the study. The effects of D-003 on collagen-induced platelet aggregation, bleeding time (BT) and coagulation parameters (prothrombin time and kaolin-activated thromboplastin time) were also investigated. Most blood biochemistry and hematological parameters were assessed at baseline and after 6 and 9 months of treatment, while total cholesterol (TC), triglycerides, platelet aggregation, BT and coagulation parameters were determined at baseline and after 9 months of treatment. At study completion, the animals were sacrificed. D-003 at a dose of 200 and 400 mg/kg significantly reduced TC (p < 0.05), significantly inhibited platelet aggregation and increased BT compared with levels in controls. Data analyses of body weight gain, food consumption, clinical observations, the remaining blood biochemistry and hematology indicators (including coagulation parameters, organ weight ratios and histopathological findings) showed no trends with D-003 doses or significant differences between control animals and treated groups. In conclusion, D-003 administered for 9 months to beagle dogs induced the expected effects with no evidence of drug-related toxicity.  相似文献   

9.
The parameters of mineral metabolism, a lipid peroxidation (LPO) process, and the efficacy of antioxidant enzyme preparations were studied in rats with an osteoporosis model induced by the administration of prednisolone in a daily dose of 100 mg/kg (i.p.) over 3 days, which is analogous to a pulsed therapy schedule in clinics. The treatment with glucocorticosteroid enhanced the excretion of hydroxyproline and inorganic phosphates with urine, increased the LPO rate and antioxidant activity of the blood serum, and decreases the level of ceruloplasmin and the catalase activity in the blood. A prophylactic treatment with dimephosphon (208 mg/kg, p.o.) and xydiphone (45 mg/kg, p.o.) prevents from the prednisolone-induced LPO activation. Dimephosphon, in contrast to xydiphone, also prevents from a prednisolone-induced increase in the excretion of hydroxyproline and inorganic phosphates with urine.  相似文献   

10.
D-003 is a mixture of high molecular weight aliphatic primary acids purified from sugar cane wax with antiplatelet and cholesterol-lowering effects. Previous studies showed that D-003 (10-20 mg/day) administered for a short time inhibits platelet aggregation, 14 days being the longest duration investigated. This study was conducted to investigate the effects of D-003 (5 and 10 mg/day) for 30 days on platelet aggregation in normocholesterolemic subjects. This report shows the effects of D-003 on platelet aggregation to arachidonic acid (AA) (1.5 mM), collagen (2 microg/ml) and adenosine 5'-diphosphate ADP (2 microM) assessed at baseline and at treatment completion. Fifty-four subjects were randomized to placebo or D-003 (5 or 10 mg/day) for 30 days. Platelet aggregation to AA, collagen and ADP were assessed. D-003 at the lowest dose (5 mg/day) significantly but modestly inhibited (p < 0.01) platelet aggregation to AA (5.0%) and (p < 0.01) to collagen (7.5%). D-003 at 10 mg/day inhibited (p < 0.001) platelet aggregation to AA and collagen (p < 0.01) by 20.3% and 14.7%, respectively. ADP-induced aggregation, however, was unchanged. D-003 at 10 mg/day, but not at 5 mg/day, lowered (p < 0.01) plasma fibrinogen. D-003 (5 and 10 mg/day) reduced low-density lipoprotein cholesterol (LDL-C) by 17.7% and 26.4%, respectively, and total cholesterol (TC) by 14.5% and 18.5%, while at 10 mg/day, but not at 5 mg/day, it increased high-density lipoprotein cholesterol (HDL-C) by 9.6%. Triglycerides, however, were unchanged with D-003. No disturbances in safety indicators were induced with D-003. One subject (D-003 5 mg/day) discontinued the study and four patients (three taking D-003 and one taking placebo) reported adverse effects (AE) (headache in two patients taking D-003 and one patient taking placebo, and polyphagia in one patient taking D-003). In conclusion, D-003 (5-10 mg/day) for 30 days inhibited platelet aggregation to AA and collagen but not to ADP Therefore, the antiplatelet effect was present with the longer treatment, even at a dose of 5 mg/day. The cholesterol-lowering effects of D-003 were consistent with those expected for such a short treatment. In addition, D-003 at 10 mg/day significantly lowered plasma fibrinogen. The treatment was well tolerated.  相似文献   

11.
Pamidronate is a representative of bisphosphonates, which are effectively used in the treatment of bone diseases. Although a number of properties of pamidronate have been recognized which influence the metabolic process in bones, the issue of the effect of bisphosphonates on the function of blood circulation and autonomic nervous system in osteoporotic bones remains open. In order to clarify this problem, the present study concentrated on the effects of pamidronate on catecholamine action on blood pressure in the marrow cavity in rats with prednisolone-induced osteoporosis. The animals were divided into 3 groups: I - control rats; II - rats which were given prednisolone at the dose of 5 mg/kg, im, for 3 weeks; III - rats which were given prednisolone at the dose of 5 mg/kg, im and pamidronate at the dose of 3 mg/kg, sc together, for 3 weeks. The experiments demonstrated that rats with prednisolone-induced osteoporosis displayed a decreased blood pressure in the marrow cavity. In addition, a disordered action of catecholamines (norepinephrine and epinephrine) on blood pressure in the marrow cavity of osteoporotic bone was observed. Pamidronate administration in osteoporotic rats resulted in smaller increases in the blood pressure caused by norepinephrine and epinephrine in the marrow cavity of long bones.  相似文献   

12.
The aim of the present study was to investigate the effects of alpha-escin on the experimental prednisolone-induced osteopenia. The experiments were carried out on male Wistar rats of initial body mass 240-310 g, divided into 4 groups (n = 6): I (C)-control, II (E)-alpha-Escin, III (P)-Prednisolone, IV (E + P)-Prednisolone + alpha-escin. Prednisolone (5 mg/kg i.m. daily) and/or alpha-escin (100 mg/kg p.o. daily) were administered for 28 days. Studies into the effect of alpha-escin on the development of steroid-induced osteopenia included the determination of an increase in body and adrenal glands mass in rats, determination of macrometrical parameters, of calcium and other minerals density in examined bones and determination of mechanical endurance of femoral bone. The carried-out experiments indicated that the p.o. administration of 100 mg/kg of alpha-escin for 28 days to sexually mature male rats with experimental steroid-induced osteopenia caused slight protective action on bone tissue against unfavourable influence of prednisolone manifested by enhancement of mechanical features of femoral bone.  相似文献   

13.
To examine the effects of Panax notoginseng saponins (PNS), the main active components of Panax notoginseng, on ovariectomy-induced osteoporosis in rats. A total of 72 six-month-old female rats were randomly assigned to sham-operated group and five ovariectomized (OVX) groups: OVX with distilled water (5 ml/kg/day, p.o.), OVX with graded doses of PNS (75, 150, 300 mg/kg/day, p.o.), and OVX with nilestriol (1 mg/kg/week, p.o.). Animals were sacrificed after a 13-week treatment course. Compared with the OVX group, PNS administration prevented OVX-induced decrease in bone mineral density (BMD) of lumbar vertebrae and total femur, and significantly increased bone structural biomechanical properties. Improvements of BMD and biomechanical properties were accompanied by the beneficial changes of PNS on trabecular microarchitecture in the tibial metaphysis. PNS at the highest dose significantly prevent decrease in trabecular bone volume over bone total volume, trabecular number, trabecular thickness, connectivity density, and increase in trabecular separation and structure model index in OVX rats. The bone-modulating effects of PNS may be due to the increased bone formation and decreased bone resorption, as was evidenced by the elevated level of serum alkaline phosphatase and decreased level of urinary deoxypyridinoline. PNS treatment is able to enhance BMD, bone strength, and prevent the deterioration of trabecular microarchitecture without hyperplastic effect on uterus. Therefore, PNS might be a potential alternative medicine for the prevention and treatment of postmenopausal osteoporosis.  相似文献   

14.
D-003 is a mixture of very high molecular weight aliphatic acids purified from sugar cane wax showing cholesterol-lowering and antiplatelet effects proven in experimental and clinical studies. Experimental evidence indicates that inhibition of platelet aggregation induced by D-003 is associated with a reduction of thromboxane B2 (TxB2) and an increase of prostacyclin (Pgl2) serum levels. This double-blinded, randomized, placebo-controlled study was undertaken to investigate whether D-003 (20 mg/day) modifies serum levels of TxB2 and Pgl2 and inhibits platelet aggregation in human healthy volunteers. Thirty-one subjects were randomized to placebo or D-003 at 20 mg/day for 14 days. Serum levels of TxB2 and Pgl2 and platelet aggregation to arachidonic acid (AA) (1.75 mM) and collagen (1 microg/ml) were assessed. D-003 (20 mg/day) significantly reduced (p < 0.001) TxB2by 36.4% and increased Pgl2 serum levels by 31% compared with baseline, and these changes were different from placebo. As expected, D-003 significantly inhibited (p < 0.001) platelet aggregation to AA (81.9-65.6%) and to collagen (75.3-62.3%). No subject withdrew from the study. No drug-related disturbances were observed. We conclude that D-003 at 20 mg/day for 14 days significantly inhibited platelet aggregation to AA and collagen and reduced TxB2 and increased Pgl2 serum levels. These results are consistent with those observed in experimental models, indicating that the antiplatelet effect of D-003 is associated with the observed changes on the levels of AA metabolites. Further studies, however, should explore the mechanism involved in this action in greater depth.  相似文献   

15.
D-003, a mixture of high molecular weight acids, inhibits cholesterol synthesis prior to mevalonate and prevents osteoporosis induced by ovariectomy in rats, and both osteoporosis and osteonecrosis induced by corticoids in rats. The aim of this study was to investigate effects of D-003 on lipopolysaccharides-induced osteonecrosis in rabbits. Animals were randomized into 5 groups: a sham and four groups injected with lipopolysaccharides: one treated orally with vehicle and three with D-003 (5, 25 and 200 mg/kg, respectively) during four weeks. We assessed the effects of treatments on the incidence of osteonecrosis (number of animals with osteonecrosis lesions/animals per group), the mean numbers and areas of osteonecrosis per animal and on the mean sizes of the bone marrow fat cells. The incidence of osteonecrosis in the groups of D-003 25 and 200 mg/kg was significantly lower than in the positive controls. The reduction of osteonecrosis increased with the doses, but significant dose-dependence relationship was not achieved. D-003 significantly and dose-dependently decreased the number of osteonecrosis lesions per animal as compared to the positive controls. Likewise, the mean osteonecrosis areas in the proximal femoral and humeral bones were significantly decreased by D-003. The injection of lipopolysaccharides significantly increased the average size of bone marrow fat cells as compared to the negative controls, and such increase was significantly and markedly reduced with D-003. It is concluded that D-003 reduced the incidence, number and percent areas of osteonecrosis lesions, and the size of bone marrow fat cells, a marker of adipogenesis, in rabbits with lipopolysaccharides-induced ostenonecrosis.  相似文献   

16.
D-003 is a mixture of long-chain fatty acids purified from sugarcane wax that inhibits both cholesterol synthesis prior to mevalonate formation, and lipid peroxidation. D-003 has been shown to prevent bone loss and bone resorption in ovariectomized rats, and significantly improves bone resorption markers in postmenopausal women with reduced bone mineral density. As hormone-replacement therapy, D-003 displays cholesterol-lowering and anti-resorptive effects. We have studied its potential oestrogenic activity in-vivo using the uterotrophic assay. Rats were randomly distributed into five groups: a sham-operated group and four groups of ovariectomized rats, one treated with vehicle, one with D-003 (50 mg kg(-1)), one with oestradiol benzoate (30 microg kg(-1)) and one with D-003 (50 mg kg(-1)) plus oestradiol benzoate (30 microg kg(-1)). Treatments were administered for 14 days. Ovariectomy decreased the values of relative uterus weight, epithelium cell height and endometrial thickness compared with sham-operated rats, and these effects were all significantly reduced with oestradiol benzoate, but not with D-003. Concurrent administration of D-003 and oestradiol benzoate had statistically similar effects on all variables as oestradiol benzoate alone. In conclusions, D-003 orally given at 50 mg kg(-1), a dose that prevents bone loss and bone resorption in ovariectomized rats, did not display oestrogenic/anti-oestrogenic activity in-vivo, as assessed in the uterotrophic assay.  相似文献   

17.
D-003 is a mixture of very high molecular weight aliphatic primary acids purified from sugar cane (Saccharum officinarum, L.) wax, in which octacosanoic acid is the most abundant component. Previous experimental studies have shown that D-003 not only shows cholesterol-lowering and antiplatelet effects, but also offers strong protection against plasma lipoprotein oxidation. Acute hepatotoxicity induced by CCL4 in rats has been related to an increased rate of lipid peroxidation, and different antioxidant compounds have been revealed to be effective in this model. The aim of this study was to investigate the effects of D-003 in acute hepatotoxicity induced by CCL4 in rats. Male Sprague Dawley rats were randomly distributed in four experimental groups as follows: group 1: negative control rats; group 2: positive control rats (CCL4-treated); groups 3 and 4 rats with liver damage induced by CCL4 and treated with D-003 at 25 and 100 mg/kg, respectively. Acute liver injury was induced by CCL4 suspended in olive oil and intraperitoneally administered at 1 ml/kg. Eighteen hours after CCL4 dosing, the rats were anesthetized with ether and their livers were removed for histopathological studies. D-003 at 25 and 100 mg/kg significantly (p < 0.01) decreased the percentage of ballooned cells and hepatocytes with lipidic inclusions and increased the percentage of normal hepatocytes compared with that in positive controls in a dose-dependent manner. The percent inhibitions of the occurrence of ballooned cells and hepatocytes with lipids were marked (75% and 50%, respectively) with the high dose (100 mg/kg). The percent of turgent hepatocytes was also significantly reduced compared with that in positive controls, but this effect was not dose-dependent. No histological alterations in the liver sections of negative controls were found. Necrotic areas and inflammatory infiltrate were observed in the liver of 7/8 (87.5%) of positive controls. In turn, D-003 dramatically reduced both necrotic areas and inflammatory infiltrate and was present in only 1/8 (12.5%) animals treated with D-003 25 mg/kg and in none (0%) of the animals treated with 100 mg/kg. D-003 protected against the histological changes characteristic of CCL4-induced hepatic injury in rats, in which the process of lipid peroxidation plays the main role. The relationship between this protective action of D-003 on this experimental model and its antioxidant effects needs to be further investigated before definitive conclusions are drawn.  相似文献   

18.
Increased platelet aggregation contributes to vascular risk. D-003, a mixture of high molecular weight sugarcane wax acids, has shown antiplatelet effects in experimental models and healthy volunteers. This randomised, double-blinded, placebo-controlled study investigated the effects of titrated doses of D-003 (5-20 mg/d) on platelet aggregation in hypercholesterolemic patients. After a 4-week baseline phase, 56 patients were randomised to D-003 5 mg/d or placebo. The doses were doubled every 15 days if arachidonic acid (AA)-induced platelet aggregation was not inhibited at least by 15%. AA (0.75 and 1.5 mmol/L) and collagen (1 microg/mL)-induced platelet aggregation, laboratory and physical safety indicators were assessed at baseline and every 15 days thereafter, when adverse events (AE) were also reported. No significant change of platelet aggregation was found in the placebo group. After 15, 30 and 45 on therapy, D-003 reduced platelet aggregation induced with both AA 0.75 mmol/L (18.1%, 19.0% and 30.3%, respectively) and AA 1.5 mmol/L (17.0%, 16.3% and 22.5%, respectively), and also collagen-induced platelet aggregation (26.6%, 20.8% and 29.4%) (p < 0.01 at days 15 and 30 versus placebo, p < 0.0001 at study completion). The mean inhibition of platelet aggregation with D-003 at day 15, at which all patients had received the lowest dose, was over 15%. Nineteen out of 28 D-003 randomised patients (67.9%) required dose titration to achieve such goal. At trial completion, the mean estimated dose was 11.6 mg/d. D-003 lowered low-density lipoprotein (22.0 %), total cholesterol (14.7%) and raised high-density lipoprotein-cholesterol (10.9%) (p < 0.0001 versus placebo). Six patients (2 placebo, 4 D-003) withdrew from the trial, none due to AE. D-003 did not modify the safety indicators with respect to placebo. Four patients (2 placebo, 2 D-003-treated) reported AE: pruritus and increased blood pressure (2 placebo) and rash and polyphagla (2 D-003). In conclusion, D-003 (5-20 mg/d) given as doses titrated every 15 days (5-20 mg/d) inhibited AA- and collagen-induced platelet aggregation in hypercholesterolemic patients and was well tolerated.  相似文献   

19.
The ability of bromocriptine (BRC), a selective dopamine D-2 receptor agonist, to induce yawning responses was studied in rats pretreated with reserpine and -methyl-p-tyrosine (-MPT). BRC (1–20 mg/kg IP) evoked yawning responses, which were pronounced at 2.5 mg/kg and characterized by the head moving downward. Higher doses of BRC (5–20 mg/kg) dose-dependently delayed the onset and peak time of yawning. A low dose of the selective D-1 dopamine receptor agonist SK&F38393 did not induce yawning but enhanced the BRC-induced response. Pretreatment with reserpine (1 and 5 mg/kg SC), -MPT (100 and 300 mg/kg IP) and reserpine (1 mg/kg) plus -MPT (100 mg/kg) was able to significantly reduce BRC-induced yawning. The inhibitory effects were prevented by a low dose of SK&F38393 (0.5 mg/kg IP). In particular, combined treatment with reserpine (5 mg/kg) and BRC (10 and 20 mg/kg) elicited upright fighting and jumping behaviors which were inhibited by haloperidol (1 mg/kg IP), a non-selective D-1 and D-2 receptor antagonist, SCH23390 (0.05 mg/kg SC), a selective D-1 receptor antagonist, or sulpiride (20 mg/kg IP), a potent D-2 receptor antagonist, and were potentiated by SK&F38393 (0.5 mg/kg). SCH23390 (0.05 mg/kg) decreased BRC-induced yawning and the apomorphine (low doses)-induced potentiation of BRC yawning, and prevented the apomorphine (high doses)-induced reduction of BRC yawning. SCH23390 also inhibited apomorphine-induced stereotypy and BRC-induced potentiation of apomorphine stereotypy. Furthermore, haloperidol (0.02 and 1.0 mg/kg IP), sulpiride (20 mg/kg IP) or scopolamine (0.5 mg/kg IP) inhibited BRC-induced yawning, but prazosin (1.0 and 3.0 mg/kg IP), an -1 receptor antagonist, did not affect this behavior. These results suggest that BRC-induced yawning may be mediated via presynaptic dopaminergic neuron activity and that BRC, in addition to the stimulation of dopamine D-2 receptors, appears to require endogenous dopamine or receptor activation by another dopamine agonist (D-1 agonist) for the induction of yawning, stereotypy and upright fighting responses. The ability of dopamine agonists to induce these behaviors seems to depend apon the potency and ratio of D-2 versus D-1 receptor activity.  相似文献   

20.
D-003 is a mixture of high molecular weight sugarcane wax aliphatic primary acids with cholesterol-lowering, anti-platelet and antioxidant effects. This study investigated the long-term oral toxicity and carcinogenicity of D-003 in Sprague Dawley rats of both sexes, randomly distributed into four groups: a control group, treated only with the vehicle, and three treated with D-003 (50, 500 and 1500 mg/kg). All treatments were given orally for 24 months. Mortality (survival analysis), clinical symptoms, weight gain, food consumption, organ weights, time-to-tumour or tumour incidence data were not shown between group differences or trends. With the exception of serum cholesterol levels, lower in D-003-treated groups (500 and 1500 mg/kg) than in the controls, no other difference in blood indicators was found. D-003 did not increase the frequency of neoplastic and non-neoplastic lesions compared with the controls. The occurrence of all malignant and mammary tumours in D-003-treated females was lower than in the controls. The lesions observed were consistent with spontaneous lesions reported in this species. In conclusion, D-003 is not toxic or carcinogenic when given orally to Sprague Dawley rats up to 1500 mg/kg for 2 years, and 1500 mg/kg was a not-observable effect dose.  相似文献   

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