Discovery of a novel COX-2 inhibitor as an orally potent anti-pyretic and anti-inflammatory drug: design, synthesis, and structure-activity relationship

Cyclooxygenase (COX) has been considered as a significant pharmacological target because of its pivotal roles in the prostaglandin biosynthesis and following cascades that lead to various (patho)physiological effects. Non-steroidal anti-inflammatory drugs (NSAIDs) that suppress COX activities have been used clinically for the treatment of fever, inflammation, and pain; however, nonselective COX inhibitors exhibit serious side-effects such as gastrointestinal damage because of their inhibitory activities against COX-1. Thus, COX-1 is constitutive and expressed ubiquitously and serves a housekeeping role, while COX-2 is inducible or upregulated by inflammatory/injury stimuli such as interleukin-1β, tumor necrosis factor-α, and lipopolysaccharide in macrophage, monocyte, synovial, liver, and lung, and is associated with prostaglandin E₂ and prostacyclin production that evokes or sustains systemic/peripheral inflammatory symptoms. Also, hypersensitivity of aspirin is a significant concern clinically. Hence, design, synthesis, and structure–activity relationship of [2-{[(4-substituted)-pyridin-2-yl]carbonyl}-(6- or 5-substituted)-1H-indol-3-yl]acetic acid analogues were investigated to discover novel acid-type COX-2 inhibitor as an orally potent new-class anti-pyretic and anti-inflammatory drug. As significant findings, compounds 1–3 demonstrated potent COX-2 inhibitory activities with high selectivities for COX-2 over COX-1 in human cells or whole-blood in vitro, and demonstrated orally potent anti-pyretic activity against lipopolysaccharide-induced systemic-inflammatory fever model in F344 rats. Also compound 1 demonstrated orally potent anti-inflammatory activity against edema formation and a suppressive effect against PGE₂ production in carrageenan-induced peripheral-inflammation model on the paw of SD rats. These results suggest that compounds 1–3 are potential agents for the treatment of inflammatory disease and are useful for further pharmacological COX-2 inhibitor investigations.     

Multi-laboratory validation of very high sun protection factor values

Background: High sun protection factor (SPF) sunscreens have multiple benefits but there has not been validation of the test method for determining SPF values higher than 50. This study addresses specifically the accuracy and reproducibility of the high SPF test. Methods: Two high SPF formulations with a standard reference (SPF 15) were tested at four independent test facilities according to the 2007 FDA proposed amendments to the sunscreen monograph. Statistical analysis was performed to compare the SPF results within each lab as well as the SPF results between different labs. Results: The test formulations have overall mean values of 90.5 and 70.7. There was no statistically significant difference between the labs for either formulation and all four labs were able to statistically differentiate these two levels of SPF values. The coefficients of variance (CV) for the high SPF formulations were comparable to those of the corresponding SPF 15 reference within each lab. Conclusions: The data show that SPF values above 50 and up to at least 90 can be measured by multiple laboratories with accuracy and reproducibility.     

Efficacy of broad-spectrum sunscreens against the suppression of elicitation of delayed-type hypersensitivity responses in humans depends on the level of ultraviolet A protection

Sunscreens have been designed to protect against sunburn and their efficacy has, therefore, been labeled by the so-called sun protection factor (SPF). Although this value is well determined using a standardized protocol and it affords a good evaluation of the protection against erythema it may be inadequate to provide a relevant measurement of efficacy against other biologic damages. This is particularly true when action spectra and threshold dose are different from those of erythema. In the case of ultraviolet (UV)-induced immune suppression, the action spectrum is not known, so it cannot be asserted that SPF may accurately predict the level of protection against this endpoint. We addressed this issue by measuring in human volunteers the ability of two broad-spectrum SPF 15 sunscreens with different ultraviolet A (UVA) protection levels, to prevent the alteration of the efferent phase of the local delayed-type hypersensitivity (DTH) response to recall antigens (Multitest Pasteur/Mérieux, Lyon, France) after acute solar-simulated UV exposure. We first determined the ultraviolet radiation (UVR) dose needed to induce a significant DTH inhibition in several groups of 15 volunteers. Two minimal erythemal doses (2 MED) were found to be the minimal immunosuppressive dose (MISD). As a result, the immune DTH response is reduced in average by 36%. The lower doses tested (0.5 and 1 MED) were ineffective. Sunscreen-treated groups were exposed to either 1 or 2 MED x SPF doses. As expected, no alteration in DTH response was observed in the groups exposed to 1 MED x SPF whatever the sunscreen applied. In contrast, after exposure to 2 MED x SPF, the DTH response remained unaltered in the group pretreated with the sunscreen product with the higher protection in the UVA range but was significantly suppressed by 55.7% in the group pretreated with sunscreen with a much lower protection in the UVA range. These data suggest that SPF may not be sufficient to predict the ability of sunscreens to protect from UV-induced immune suppression. Determining the level of UVA protection is particularly needed, as UVA seems to have a relatively low contribution to erythema but is highly involved in immunosuppression.     

The effect of sunscreen on melanoma risk

Total cumulative sun exposure is associated with the development of squamous cell and basal cell cancers, whereas intense intermittent sun exposure is associated with the development of melanoma. Exposure to UV radiation is the only known modifiable cause of melanoma, but the role of sunscreen in melanoma prevention remains somewhat controversial. This article discusses how UV radiation contributes to the pathogenesis of melanoma, how sunscreen modulates the action of UV radiation on the skin, and the effect of sunscreen on the risk of developing melanoma. A review of available sunscreen agents and their sun-protective properties is also included.     

Examination of the effects of methotrexate on histological and steroid receptor changes in the endosalpinx of the rat

Objectives

Methotrexate (MTX) has been a prevalent drug in conservative treatment of unruptured tubal pregnancy for many years. However, few researchers have performed morphological and protein analysis simultaneously to evaluate the specific toxic effects of MTX on the fallopian tubes. The aim of this study was to investigate acute and long-term toxic effects of increasing doses of MTX on the fallopian tubes and a possible dose–effect relationship. We also discuss the potential implications for subsequent pregnancies.

Study design

At the 10th day and the 2nd and 3rd months after MTX treatment, a total of 108 females SD rats in estrus stage (27 rats in each group) were collected according to the dose of MTX i.p.: 1, 2, 5 mg/kg body weight in groups I, II and III respectively and physiological saline i.p. in group IV for control. Nine rats in each group were killed at each time point and tissues close to the ampulla of the fallopian tubes were dissected for HE staining and routine histological observation. Estrogen receptor (ER) and progesterone receptor (PR) expression was detected by immunohistochemistry and Western blot.

Results

Morphological observation showed acute endosalpingitis in group I, becoming more intense with increasing doses of MTX in groups II and III in a reversible mode. Expression of ER in the endosalpinx significantly decreased in parallel with increasing doses of MTX in a dose–effect manner, which was reversible in groups I and II and irreversible in group III. Furthermore, ER and PR could recover close to normal levels in groups I and II after the 3rd month, while they could not restore to normal in group III.

Conclusions

These results provide the first evidence that MTX (≥5 mg/kg) can induce long-term, irreversible damage to steroid hormone receptors in the fallopian tubes in a dose-dependent manner. We tentatively suggest that MTX should be used in a relatively small and safe range of dosage in order to avoid impairment and potential risk of subsequent tubal pregnancy or infertility.     

SPF级新西兰兔脏器参数、血液指标、颈动脉血压、心率、心室压的测定与比较

目的 准确测定SPF新西兰兔生物学特性尤其是疾病相关的指标,并进行性别间比较。 方法 取70-80日龄左右SPF新西兰兔30只,饲养一周后,精确称量体重及主要脏器重量;采集动脉血测定血液生理、生化、血气指标;颈动脉插管测定动脉压,呼吸支持情况下进行开胸测定心室压。 结果 雄性与雌性新西兰兔比较： 甲状腺、肾上腺、肝的质量差异有显著性意义（P＜0.05或P＜0.01）;脑、脑垂体、甲状腺的脏器系数差异有显著性意义（P＜0.05或P＜0.01）;甲状腺、肾上腺、肝的脏脑比系数差异有显著性意义（P＜0.05或P＜0.01）。红细胞平均体积、平均血红蛋白量的差异有显著性意义（P＜0.05或P＜0.01）;谷氨酰转肽酶、淀粉酶的差异有显著性意义（P＜0.05或P＜0.01）;血气分析、心率、颈动脉收缩/舒张压,左心室收缩/舒张压,右心室收缩/舒张压不存在性别间差异。 结论 性别对新西兰兔脏器重量及血液生理生化指标有一定影响,而血气、血压、心率及心室压等不存在性别间差异。     

不同月龄SPF级SD大鼠血液学及生化指标的变化

目的探讨不同生长期SPF级SD大鼠的血液学指标及生化指标的差异。方法采用血液分析仪分别测定SPF级SD大鼠2月龄、3月龄、4月龄、7月龄、8月龄时血液白细胞(WBC),红细胞(RBC),血红蛋白(HGB),红细胞压积(HCT),平均红细胞体积(MCV),平均红细胞血红蛋白量(MCH),平均红细胞血红蛋白浓度(MCHC),血小板(PLT)等指标;运用全自动生化测定仪测定其谷丙转氨酶(ALT)、谷草转氨酶(AST)、总蛋白(TP)、白蛋白(ALB)、血糖(GLU)、尿素氮(BUN)、肌酐(CREA)、甘油三酯(TG)等指标。结果结果表明大鼠RBC数量随年龄增长逐渐增大,雄性大鼠PLT数量逐渐增大,MCV减小,雌性HGB、HCT逐渐增大,且WBC、RBC、HGB、HCT数量随年龄增长呈现雌雄差异,雌性值偏小;大鼠各血液学指标均有较大的波动,其中以WBC和PLT的波动范围最大;随年龄的增长,雄性大鼠TP值逐渐减小;雌性大鼠TG逐渐升高;TP、ALB、BUN呈现雌雄差异,且雌性偏高;大鼠各生化指标均有较大的波动,以AST的波动范围最大。结论研究结果表明:大鼠的部分血液学及生化学指标存在性别及年龄的差异。     

前列腺上皮内瘤DNA 倍体、细胞周期的分析

 目的 探索DNA倍体类型、细胞周期在前列腺上皮内瘤中诊断和鉴别诊断的价值。方法 应用细胞图像分析技术检测前列腺上皮内瘤（PIN）细胞的平均DNA含量、DNA平均倍体值及细胞周期的各个时相的变化。同时与良性前列腺增生症（BPH）、前列腺癌（PCa）比较。结果 PIN组异倍体率为70％，前列腺上皮内瘤DNA平均倍体值、G0／G1期细胞比率、S期细胞比率介于良性前列腺增生症和前列腺癌之间。结论 DNA异倍体、较高S期细胞比率是前列腺上皮内瘤重要生物学特性。对于前列腺上皮内瘤的鉴别诊断具有一定参考价值。     

SPF级实验动物设施改建工艺设计探讨

目的对SPF级实验动物设施的建立和管理进行初步探讨。对象把武汉生物研究所的清洁级实验动物设施改建为SPF级设施。设计原则SPF级实验动物生产饲养和实验饲养设施条件配套,人、物、动物、空气流的工艺流程合理。结果改造后的SPF级实验动物设施的环境参数符合国标要求,已取得相应的许可证。