Influence of Novel Gallium Complexes on the Homeostasis of Some Biochemical and Hematological Parameters in Rats

Chronic overexposure to cobalt (Co) may result in neurotoxic effects, but the mechanism of Co-induced neurotoxicity is not yet well established. Our study was conducted to determine whether Co is associated to the induction of central nervous system damage in pregnant rats and their progeny. Twelve pregnant female rats were randomly divided into 2 groups: group I served as controls and group II received Co (350 mg/L, orally). Treatments started from the 14th day of pregnancy until day 14 after delivery. Co concentration in plasma was higher in the treated groups than in the controls. Exposure to Co also increased the levels of MDA, PCO, H₂O₂, and AOPP, while Na⁺K⁺-ATPase and Mg²⁺-ATPase, AChE, and BuChE activities decreased in the cerebrum and cerebellum of suckling pups. A smear without ladder formation on agarose gel was also shown in the cerebrum and cerebellum, indicating random DNA degradation. A reduction in GPx, SOD, CAT, GSH, NPSH, and vitamin C values was observed. The changes were confirmed by histological results. In conclusion, these data showed that the exposure of pregnant and lactating rats to Co resulted in the development of oxidative stress and the impairment of defense systems in the cerebrum and cerebellum of their suckling pups.     

SD雌性大鼠性发育早期性器官等脏器和性激素的动态变化

目的探讨正常SD雌性大鼠性成熟前不同日龄段的脏器与促黄体生成素（LH）、促卵泡素（FSH）、雌二醇（E2）等性激素的变化及其关系。方法从生产群中取出60窝密度状态一致的SD大鼠,在不同日龄随机选取雌性大鼠,检测15、25、32、40日龄时大鼠体重、主要脏器指数,子宫、卵巢组织变化和15、25、32、40、60日龄大鼠血清LH、FSH、E2水平。结果记录了SD雌性大鼠性成熟前各脏器指数和卵巢、子宫组织变化,结果显示大鼠卵巢、子宫的增长速度大于体重的增长,而其他脏器增速大都小于体重的增长。本研究还记录了血清LH、FSH、E2水平在不同日龄段的变化规律,表明血清LH、E2浓度在32日龄时出现较为明显升高。结论不同日龄大鼠脏器指数的动态变化提示大鼠性器官在性发育早期得到机体的优先发育。血清LH、E2水平在32日龄时有了明显升高,提示性腺轴功能已经激活。60日龄大鼠血清性激素水平的波动类似于动情周期的规律性变化,推测大鼠在60日龄前即已进入性成熟,这些结果将为大鼠性发育的相关研究提供重要的参考数据。     

Evaluation of Memory Enhancing Clinically Available Standardized Extract of Bacopa monniera on P-Glycoprotein and Cytochrome P450 3A in Sprague-Dawley Rats

Bacopa monniera is a traditional Ayurvedic herbal medicine used to treat various mental ailments from ancient times. Recently, chemically standardized alcoholic extract of Bacopa monniera (BM) has been developed and currently available as over the counter herbal remedy for memory enhancement in children and adults. However, the consumption of herbal drugs has been reported to alter the expression of drug metabolizing enzymes and membrane transporters. Present study in male Sprague-Dawley rat was performed to evaluate the effect of memory enhancing standardized extract of BM on hepatic and intestinal cytochrome P450 3A and P-glycoprotein expression and activity. The BM (31 mg/kg/day) was orally administered for one week in BM pre-treated group while the control group received the same amount of vehicle for the same time period. The BM treatment decreased the cytochrome P450 3A (CYP3A) mediated testosterone 6β-hydroxylation activity of the liver and intestine by 2 and 1.5 fold, respectively compared to vehicle treated control. Similarly pretreatment with BM extract decreased the expression of intestinal P-glycoprotein (Pgp) as confirmed by Western blot analysis but did not alter the expression of hepatic Pgp. To investigate whether this BM pretreatment mediated decrease in activity of CYP3A and Pgp would account for the alteration of respective substrate or not, pharmacokinetic study with carbamazepine and digoxin was performed in BM pre-treated rats and vehicle treated rats. Carbamazepine and digoxin were used as CYP3A and Pgp probe drugs, respectively. Significant increase in AUC and Cmax of carbamazepine (4 and 1.8 fold) and digoxin (1.3 and 1.2 fold), respectively following the BM pre-treatment confirmed the down regulation of CYP3A and Pgp.     

Effect of the Juice of Lime (Citrus Aurantifolia) on Estrous Cycle and Ovulation of Sprague-Dawley Rats

ObjectiveTo determine the effect of lime juice on the estrous cycle and ovulation of cyclic female rats.MethodsTwenty-five adult female Sprague-Dawley rats were used. The study was divided into 2 experiments (I and II). In experiment I, 15 rats were randomly subclassified into 3 groups (Ia, Ib, and Ic) of 5 rats each. The estrous cycles of the rats were studied for the first 16 days to establish cyclicity, after which lime juice was administered by gastric gavage for the next 24 days. Rats in group Ia received 1 mL of undiluted lime juice, rats in group Ib received 1 mL of 50% diluted lime juice, and rats in group Ic (control animals) received only distilled water. In experiment II, 10 female rats were used and were categorized into 2 groups (IIa and IIb), with 5 rats in each group. Rats in group IIa received 1 mL of undiluted lime juice during the morning of proestrus, and those in group IIb received only distilled water on the day of proestrus. The rats were killed the next day with use of chloroform anesthesia. The upper parts of the oviducts were excised and examined under the light microscope for assessment of the number of ova shed.ResultsThere was an irregular pattern in all phases of the estrous cycle of 100% of the rats given undiluted lime juice and in 80% of those given 50% diluted lime juice. There was a significant (P = .001) reduction in the number of ova shed in rats administered undiluted lime juice in comparison with the control animals. Ovulation was partially blocked, as shown by the reduced number of ova observed in the oviducts from the rats given undiluted lime juice (5.10 ± 2.37) in comparison with the control rats (12.70 ± 1.14).ConclusionIn rats, lime juice causes irregularity of the estrous cycle, partially blocks ovulation, and may possibly compromise fertility. (Endocr Pract. 2010;16:561-565)     

Biological Fractionation of Lead Isotopes in Sprague-Dawley Rats Lead Poisoned via the Respiratory Tract

Objectives

It was considered that lead isotope ratios did not change during physical, chemical, or biological processes. Thus, lead isotope ratios have been used as fingerprints to identify possible lead sources. However, recent evidence has shown that the lead isotope ratios among different biological samples in human are not always identical from its lead origins in vitro. An animal experiment was conducted to explore the biological fractionation of lead isotopes in biological systems.

Methods

24 male Sprague-Dawley (SD) rats were divided into groups that received acute lead exposure (0, 0.02, 0.2, or 2 mg/kg body weight of lead acetate) via the respiratory route every day for 5 days. Biological samples (i.e., blood, urine, and feces) were collected for comparison with the lead acetate (test substance) and the low-lead animal feed (diet) administered to the rats. The lead isotope ratios were determined by inductively coupled plasma mass spectrometry (ICP-MS).

Results

There are significant differences (p<0.05) in lead isotope ratios between blood, urine, and feces. Moreover, a nonlinear relationship between the blood lead concentration and the blood lead isotope ratios was observed. There is also a threshold effect to the fractionation function. Only the blood isotope ratio of ²⁰⁴Pb/²⁰⁶Pb matches the test substance well. As for feces, when ²⁰⁴Pb/²⁰⁶Pb ratio is considered, there is no significant difference between feces-test substance pairs in medium and high dose group.

Conclusions

The biological fractionation of lead isotopes in SD rats was observed. Moreover, there might be a threshold for the biological fractionation of lead isotopes which is depending on whole blood lead level. It is considered to be more reliable that we compared the isotope ratios of potential lead hazards with both blood and feces lead fingerprints especially for ²⁰⁴Pb/²⁰⁶Pb ratio under high-dose exposure.     

A Study on the Safety and Effects of Amorpha fruticosa Fruit Extract on Spontaneously Hypertensive Rats with Induced Type 2 Diabetes

Metabolic syndrome is characterized by a variety of diagnostic criteria: obesity, dyslipidemia, type 2 diabetes, and arterial hypertension. They contribute to the elevated risk of cardiovascular morbidity and mortality. The potential for Amorpha fruticosa L. (Fabaceae) to improve diabetes and metabolic disease is promising, based on in vitro tests. This is why a further investigation of the species is needed. Additionally, a toxicity review in relation to safety revealed that to date, there are no published data regarding the toxicity of A. fruticosa towards humans. This species could provide abundant and cheap resources because it is an aggressive invasive plant that grows almost unrestrictedly. The objective of this study was to evaluate the acute toxicity of a purified extract of A. fruticosa (EAF), and to assess its antioxidant, antihypertensive, and antihyperglycemic activity in streptozotocin-induced diabetic spontaneously hypertensive rats (SHRs). The EAF was slightly toxic (LD₅₀ = 2121 mg/kg, b.w.) when administered orally, and moderately toxic (LD₅₀ = 316 mg/kg, b.w.) at intraperitoneal administration, both in mice. The oral administration of EAF (100 mg/kg) for 35 days to SHRs caused significant decreases in the systolic pressure, blood glucose levels, and MDA quantity. It also increased the hepatic level of the endogenous antioxidant GSH, not only in diabetic SHRs, but also in the control group. An additional potential benefit to human health might be conferred through the environmental management of A. fruticosa based on its large-scale use for medicinal purposes, as this aggressive invasive species brings problems to natural habitats in many European countries.     

Hematological and Blood Biochemical Effects of Fasting and Subsequent Oral Administration of Endotoxin in Prepubertal Gilts

The main objective of the present study was to investigate the effects of short-term fasting in gilts on endocrinological and blood biochemical parameters and, further, the effects of subsequent oral endotoxin (ET) administration. Group 1 was fasted for 30 h and then received feed with ET added. Group 2 was fasted for 30 h but received standard feed at refeeding. In group 3, gilts were fed every 6 h for 30 h. The major effects of fasting were: gradually increased concentration of plasma prostaglandin F2α metabolite, serum total bilirubin, serum free fatty acids, and decreased serum glucose. The values were normalized within 1–4 h of refeeding. Twelve hours after refeeding, the ET-refed gilts showed higher levels of serum total bile acids and polymorphonuclear leukocytes than those in group 2. It is possible that the observed changes during fasting reflect either an increased intestinal uptake of naturally present endotoxin or a reduced endotoxin detoxifying capacity of the liver. The increased bile acid concentration and polymorphonuclear leukocyte count following refeeding with ET-feed may indicate that orally administered ET is to some extent absorbed from the gut.     

Differences in Retinal Structure and Function between Aging Male and Female Sprague-Dawley Rats are Strongly Influenced by the Estrus Cycle

Purpose

Biological sex and age are considered as two important factors that may influence the function and structure of the retina, an effect that might be governed by sexual hormones such as estrogen. The purpose of this study was to delineate the influence that biological sex and age exert on the retinal function and structure of rodents and also clarify the effect that the estrus cycle might exert on the retinal function of female rats.

Method

The retinal function of 50 normal male and female albino Sprague-Dawley (SD) rats was investigated with the electroretinogram (ERG) at postnatal day (P) 30, 60, 100, 200, and 300 (n = 5–6 male and female rats/age). Following the ERG recording sessions, retinal histology was performed in both sexes. In parallel, the retinal function of premenopausal and menopausal female rats aged P540 were also compared.

Results

Sex and age-related changes in retinal structure and function were observed in our animal model. However, irrespective of age, no significant difference was observed in ERG and retinal histology obtained from male and female rats. Notwithstanding the above we did however notice that between P60 and P200 there was a gradual increase in ERG amplitudes of female rats compared to males. Furthermore, the ERG of premenopausal female rats aged 18 months old (P540) was larger compared to age-matched menopausal female rats as well as that of male rats.

Conclusion

Our results showed that biological sex and age can influence the retinal function and structure of albino SD rats. Furthermore, we showed that cycled female rats have better retinal function compared to the menopausal female rats suggesting a beneficial effect of the estrus cycle on the retinal function.     

Effects of a Daisaikoto Extract on the Biliary Constituents in Mice and Rats

The effects of an extract of Daisaikoto (a traditional Chinese medicine) on biliary constituents was studied in mice fed with a lithogenic diet containing 0.5% cholesterol and 0.25% sodium cholate (the control diet) and in rats fed with a cholesterol-free diet. The Daisaikoto extract was added to the control diet at a level of 0.5%. A high incidence of cholesterol gallstones were found in the control mice, but not in the mice given the Daisaikoto extract. This difference was concluded to have been due to the absolute concentration of bile acid in the bile being significantly higher in the mice given the Daisaikoto extract than in the control mice. The result from rats fed with the cholesterol-free diet also demonstrated that the Daisaikoto extract caused an increase in the absolute concentration of bile acid in the bile.     

柑橘果实遮光处理对发育中的果实光合产物分配、糖代谢与积累的影响

研究了柑橘果实膨大初期遮光处理对果皮色素、果实含糖量、光合产物在果实内的分配及果实中蔗糖代谢相关酶活力变化的影响.结果表明遮光处理使果皮中的叶绿素含量迅速降低而类胡萝卜素积累缓慢,蔗糖的相对含量则明显上升.遮光处理还促进了光合产物向果皮运输,相应地降低了汁囊中光合产物分配比率,使果实汁囊中蔗糖含量下降.果皮中SS、SPS和转化酶活力在遮光处理后均有较大的提高,而汁囊中则差异不大.上述结果表明,在果实自身光合作用被抑制的条件下,果皮是通过提高酶活力来增强库强度,从而使其在与汁囊竞争中获得更多的光合产物,造成汁囊含糖量下降.     

Effect of Aqueous Extract of Glycyrrhiza glabra on the Biochemical Changes Induced by Cadmium Chloride in Rats

Biological Trace Element Research - Twenty four rats were divided into four groups (6 rats/group): 1—control group; 2—licorice (Glycyrrhiza glabra) extract: rats administered with an...     

Evaluation of the Preventive Effect of Isoflavone Extract on Bone Loss in Ovariectomized Rats

To examine a potential role for soybean phytoestrogens in postmenopausal bone loss, twenty-four 12-week-old Sprague-Dawley rats were divided randomly into 4 groups and given controlled diets for 16 weeks. The treatment groups were as followed: sham operated, ovariectomized (OVX) control, OVX + isoflavone extract (6.25 g/kg), and OVX + 17β-estradiol (4 mg/kg). OVX treatments reduced femoral and fourth lumbar vertebral bone density and mineral content (p<0.01), decreased uterine weight (p<0.01), accelerated body weight increases (p<0.05), and increased the activities (p<0.01) of both serum alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP). Supplementation with isoflavone prevented the losses of bone density and mineral content caused by OVX (p<0.01). Although both isoflavone and 17β-estradiol exhibited similar bone-sparing ability on the OVX-induced bone loss, the effect of isoflavone was not the same as that of 17β-estradiol on the serum ALP and TRAP, body weight increase, and uterine weight change. We concluded that dietary supplementation with soybean isoflavone can prevent postmenopausal bone loss via a different mechanism of estrogen in OVX rats.     

Effects of Subchronic Aluminum Exposure on the Reproductive Function in Female Rats

The aim of this study was to investigate the effects of aluminum (Al) exposure on the reproductive function in female rats. Forty female Wistar (5 weeks old) rats, weighing 110–120 g, were divided randomly into four groups. They were orally administrated with 0, 64.18, 128.36, and 256.72 mg aluminum chloride (AlCl₃) per kilogram body weight in drinking water for 120 days. Levels of Al, estrogen (E₂), progestogen (P), testosterone (T), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) in serum were measured at the end of experiment. The results showed that levels of E₂, P, FSH, and LH were significantly lower and Al concentration was significantly higher in all three Al-treated groups than those in the control group (GC). The level of T was significantly higher in the low- and medium-dose groups (GL and GM) (P < 0.05) but not in high-dose group (GH) compared with GC. The results suggest that the reproductive function of female rats is inhibited under long-term Al exposure in an Al dose-dependent manner.     

Effects of Andrographis paniculata (Burm. F.) Extract on Diabetic Nephropathy in Rats

Background:Hyperglycemia and accumulation of advanced glycation end products (AGEs) play a significant role in the development of diabetic nephropathy. Andrographis paniculata (AP) is a plant with high flavonoid content with the potential to suppress oxidative stress activity in cells and tissue. This study was aimed to investigate the role of Andrographis paniculata extract (APE) in protecting kidney damage due to the formation of AGEs in the renal glomerulus in diabetic rats.Methods:A total of 30 male Sprague Dawley rats were randomly divided into five groups as follows: normal control group, streptozocin (STZ) induced diabetic group, STZ-induced diabetic group with AP extract (100 mg/kg BW), STZ-induced diabetic rats with AP extract (200 mg/kg BW), and STZ-induced diabetic rats with APE (400 mg/ kg BW). Blood glucose levels were measured before treatment and after treatment. Serum and urine parameters were determined. Antioxidant enzymes and lipid peroxide levels were determined in the kidney along with histopathological examination.Results:The finding of this study showed that treatment APE at the dose of 200 mg/kg and 400 mg/kg ameliorated kidney hypertrophy index. SOD, catalase, and GSH activities significantly decreased in the kidney of STZ-diabetic rats compared to the normal control rats. Treatment with APE significantly decreased malondialdehyde level at the dose of 200 and 400 mg/kg BW.Conclusion:This study revealed evidence for improving diabetic retinopathy in male rats treated with Andrographis paniculata extract. APE significantly decreased oxidative stress activities in kidney of diabetic rats.Key Words: Andrographis, Diabetic Nephropathies, Streptozocin, Rats, Oxidative Stress     

Effects of acute blood removal via the sublingual vein on haematological and clinical parameters in Sprague-Dawley rats

Haematological and clinical effects were evaluated after multiple blood samplings over 24 h in the laboratory rat and for up to 22 days after collection to determine the time required for a return to baseline values. Male and female Sprague-Dawley rats (n = 7/sex/group) were bled 4 times over 24 h and blood samples of 1.2, 1.6, 2.4 and 3.2 ml were taken. There were no adverse clinical signs and no statistically significant differences in body weight, body weight gain and food consumption. The acute effect on main haematological parameters of blood removal over 24 h consisted of reductions of red blood cell count, haemoglobin and haematocrit which were similar for blood removal exceeding 7.5% and less than 15% of circulating blood volume, and the reductions were positively related to the amount of blood loss beyond 15%. Time to recover to baseline values was also proportional to the initial blood collection volume and was estimated to range from 48 h for amounts from 5% to below 7.5%, 12 days for amounts from 7.5% to up to 20% and 19 days for amounts above 20%. Recommendations are made concerning suitable blood collection regimes.