EFFECTS OF B-CAROTENE ON SALIVARY GLAND TUMORS

B-胡萝卜素对唾液腺肿瘤的作用

• 批准号: 3220385
• 负责人: SYED Q ALAM
• 金额: $ 7.65万
• 依托单位: LSU HEALTH SCIENCES CENTER
• 依托单位国家: 美国
• 财政年份: 1984
• 资助国家: 美国
• 起止时间: 1984-03-01 至 1987-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3220385
• 关键词: benzanthracenes; cancer prevention; carotene; chemical carcinogenesis; neoplasm /cancer nutrition therapy; nutrition related tag; retinaldehyde; salivary gland neoplasms; submandibular gland; vitamin therapy

The proposed investigations are designed to determine if supplementation of the diet with vitamin A or Beta-carotene would result in inhibition of the incidence and development of salivary gland tumors. The effects of delayed administration of Beta-carotene and its mechanism of action as a cancer chemopreventive agent would also be studied. Tumors will be induced in submandibular salivary glands (SMSG) of rats by injecting dimethylbenzanthracene (DMBA) into one of the gland, the contralateral gland would be injected with the vehicle alone. During the initial experiments, rats will be fed diets supplemented with different levels of vitamin A and Beta-carotene. The dietary regimens will be initiated 4 weeks prior to the DMBA treatment and continued thereafter (20-24 weeks after the DMBA treatment). The incidence and weight of the tumors will be determined in each group along with its histological evaluation after hematoxylin and eosin staining. The activity of Gamma-glutamyltranspeptidase will be determined histochemically and biochemically in the SMSG (normal versus DMBA-treated) of rats fed different diets. Similar studies using DMBA-induced salivary gland tumor model, will also be conducted to determine if a delayed supplementation of the diet with Beta-carotene is effective in inhibiting tumorogenesis. The mechanism of cancer chemopreventive effects of Beta-carotene will be investigated by determining whether it is Beta-carotene per se or its ability to be converted to vitamin A in vivo is the main reason for its antitumor effects. These studies will include comparison of the chemopreventive ability of Beta-carotene with canthaxanthin, another C40 carotenoid which is not converted to vitamin A. Studies on the levels of tissue peroxides and Alpha-tocopherol as affected by Beta-carotene feeding will also be conducted in order to develop a better understanding of the mechanism of the tumor preventive effects of Beta-carotene.

拟议的调查旨在确定是否补充 维生素A或β-胡萝卜素的饮食将导致抑制 唾液腺肿瘤的发病率和发育。 延迟的影响 β-胡萝卜素的给药及其作为癌症的作用机理 还将研究化学预防剂。 将在大鼠的下颌下唾液腺（SMSG）中诱导肿瘤 将二甲基苯乙烯（DMBA）注射到其中一个腺体中 对侧腺将仅注入车辆。 在 最初的实验，将补充不同的饮食喂食大鼠 维生素A和β-胡萝卜素的水平。 饮食方案将是 在DMBA治疗前4周开始，此后继续 （DMBA治疗后20-24周）。 发病率和重量 将在每组及其组织学上确定肿瘤 苏木精和曙红染色后的评估。 活动 γ-谷氨酰肽酶将在组织化学和 在SMSG（正常与DMBA治疗）中的生化大鼠中的生化 不同的饮食。 使用DMBA诱导的唾液腺肿瘤的类似研究 还将进行模型，以确定是否延迟补充 β-胡萝卜素的饮食可有效抑制肿瘤发生。 这 β-胡萝卜素的癌症化学预防作用机制将是 通过确定是β-胡萝卜素本身还是它的调查 能够转化为体内维生素A的能力是其主要原因 抗肿瘤效应。 这些研究将包括比较 β-胡萝卜素与canthaxanthin的化学预防能力，另一种C40 类胡萝卜素未转化为维生素A。 受β-胡萝卜素喂养影响的组织过氧化物和α-生育酚 还将进行以更好地了解 β-胡萝卜素的肿瘤预防作用机理。