The effect of genistein on IGF-1, PlGF, sFLT-1 and fetoplacental development

The mechanisms by which genistein, a phytoestrogen, affects fetoplacental development adversely are still poorly understood. It is reported that genistein ingestion modulates thyroid functions, leptin hormone, C-reactive protein, and thyroxin kinase activities. In this study, we evaluated changes in serum and placental insulin-like growth factor-I (IGF-1), placental growth factor (PIGF), and soluble fms-like tyrosine kinase-1 (sFLT-1) in pregnant rats exposed to genistein using ELISA. According to the treatments, Rats were divided into control, 2 mg genistein, and 4 mg genistein groups. Genistein groups were administered with the doses orally from gestational day (GD) one onwards until sacrifice, while the control group received an equal volume of distilled water the vehicle. At GD-12, GD-16, and GD-20, serum samples and placenta homogenates were prepared from maternal blood samples and the placenta and were analysed to determine the concentration of IGF-1, sFLT-1, and PIGF. Serum IGF-1 and PIGF were both increased in all genistein groups at GD-12 and GD-16, and at GD-20 in the 4 mg group. However, serum IGF-1and PIGF levels were decreased in the placenta from all genistein groups at GD-20. Placenta sFLT-1 levels increased at both GD-16 and GD-20 in genistein-treated rat serum. An initial decrease in placental sFLT-1 at GD-12 was followed by an increase at GD-16 and finally a decrease at GD-20 in all genistein-treated rats. The sFL-1/PlGF ratio in placenta samples of genistein-exposed rats was decreased at GD-16 and increased at GD-20, while the reverse was recorded in the serum sample at the same gestational periods. The fetoplacental growth disruption mechanism of genistein can be partly explained by its interference with placental growth factor signalling.

Acute and sub-chronic toxicity assessment and evaluation of the gastro-protective activity of polyherbal formulation “Mystomate4®” against gastric ulcer in experimental laboratory animal

Background

Ulcer remains a health challenge worldwide with antibiotics and proton pump inhibitors as major management therapy. The study investigated the acute, sub-chronic toxicity and gastrointestinal protective activity of a polyherbal formulation (Mystomate4®) used locally in Nigeria.

Methods

Oral LD50 and the sub-chronic toxicity test were determined in mice and rats. Mice were grouped into 8 groups of 8 mice each. They were dosed a graded concentration of the formulation (1.28, 2.56; 5.12; 10.24; 20.48; 40.96; 81.92; 163.84 g/kg body weight). The graded dose used was arrived at after an initial pilot study. Thereafter doses were chosen around the dose obtained from the pilot study. Animal were dosed orally and observed for sign of toxicity and number of death recorded after 24 h. The sub-chronic toxicity study was carried out for 3 months in rats at a dose of 2.5 and 5.0 g/kg body weight arrived at by titrating down the LD50 value after which some vital tissues were harvested and assessed for toxicity using relevant biomarkers. Anti-ulcer activity was evaluated in rats using ethanol, indomethacin and pylorus ligation induced ulcer models. Data were analysed with Graph Pad Prism version 5.0 using appropriate statistical method and significant level placed at p ≤ 0.05.

Results

The acute toxicity study showed an LD50 result of 22,837.21 g/kg. The sub-chronic toxicity study resulted in a significant reduction in body weight due to significant decrease (p ≤ 0.05) in feed consumption. Biochemical analyses of the blood samples showed a significant increase (p ≤ 0.05) in creatinine and albumin level in the 2.5 mg/kg female group. ALT was significantly increased in all the treated rats except in 2 mg/kg female rats. Alkaline phosphatase significantly increased in high dosed male (HM) group while blood urea:creatinine ratio was significantly lowered in all the treated groups. There was a significant increase in serum TGL in all rats while LDL was significantly increased and decreased in HM and high dosed female (HF) respectively.

Conclusion

Mystomate4® showed significant protection against ethanol and indomethacin-induced ulcer models but did not modify the gastric parameters in pylorus ligation-induced ulcer model. The polyherbal formulation is nontoxic with promising potentials for treating experimental peptic ulcer.

Modulatory role of genistein on placenta and maternal bone minerals composition: further insight into its influence on pregnancy and foetal development

Pregnancy is a crucial period with an increased need to supply necessary minerals for both the mother and the developing foetus and with a tendency of altering the maternal bone mineral density when there is no balance between demand and supply of these minerals. This study evaluated the influence of genistein on the maternal bone and placenta mineral composition. Pregnant rats were grouped into control, 2 mg/kg and 4 mg/kg genistein groups, dosed accordingly till sacrificed at different gestation days (GD). Body and placenta weights, right femur bone and placenta mineral composition were analysed. A significant decrease in body weight and percentage relative right femur bone weight at GD-20 was recorded in the 2-mg group with the reverse occurring in the 4-mg genistein group. The right femur bone Ca²⁺ and Zn²⁺ was reduced towards GD-20 in both 2-mg and 4-mg genistein groups. Genistein had no influence on placenta selenium and cadmium level, but significantly decreased zinc and lead level concentration as the gestation progressed towards GD-20. Copper level was increased at GD-16 at the doses used. Genistein modulated maternal bone mineral composition and placenta capability in retaining some heavy metals at various stages of pregnancy.

The immune system cell populations were increased in salt-induced hypertensive rats without an increase in the serum testosterone level (Short communication)

The consumption of dietary salt has significantly increased globally, especially in the developed countries. High dietary salt intake has been linked to onset and complications in hypertension with a dimorphism tendency. There is scanty information about the influence of high salt diet on the immune cell population and androgen level in circulation. Male Sprague-Dawley rats of 8 weeks old were used for this study. They were divided into control (fed 0.1% salted feed) and salt-loaded groups (fed 8% salted feed) for 8 weeks. All experimental rats were allowed access to clean drinking water; daily feed consumption was measured in addition to weekly weight. On confirmation of hypertension using PowerLab® data acquisitions system, the rats were sacrificed and blood samples were collected into EDTA and sterile sample bottles. EDTA-blood samples were used for white blood cell and CD4 counts while the serum was used for hormonal assays. All salt-loaded rats became hypertensive, with a significant increase in total white blood cell, lymphocyte, neutrophil, monocyte, and CD4 cell counts. However, the eosinophil count was significantly decreased in salt-loaded rats. This study showed no change in the serum testosterone in salt-loaded male rats compared with control. In summary, dietary salt loading while precipitating hypertension also activated increased production of white blood cells and CD4 cells without any change in the serum testosterone level.

High-Dose Perinatal Folic-Acid Supplementation Alters Insulin Sensitivity in Sprague-Dawley Rats and Diminishes the Expression of Adiponectin

The possible intake of folate in excess of the recommended upper levels is a matter of critical importance. This study was conducted to investigate the effects of prenatal and postnatal high folic acid supplementation (FAS) on glucose tolerance, insulin sensitivity, lipid metabolism, and expression of adiponectin in rats. The study included 20 female rats divided into two groups: control group and FAS group (receiving high folic acid supplemented diet). Both groups of female rats were mated and pregnancy confirmed. At parturition, the diet of 5 dams that were fed with control diet during gestation and their litters was changed to FAS diet and continued throughout lactation. Similarly, half of the dams that were previously fed with FAS diet during gestation and their litters were also changed to control diet. The remaining 5 dams in each group continued on their respective diets throughout lactation with their litters. Other dams remained on their respective diets throughout lactation. Food and water intake, body weight, lipid concentrations, insulin, and the expression of adiponectin were determined. Glucose tolerance and insulin sensitivity were also measured to evaluate glucose homeostasis. FAS significantly increased the postweaning food, water intake, triglyceride, and insulin levels but diminished insulin sensitivity in adult offspring. The expression of adiponectin in insulin-sensitive tissues was also significantly decreased and these were consistent with insulin resistance of FAS offspring. High-dose FAS may promote insulin resistance and dyslipidemia and disrupt glucose metabolism possibly by depressing adiponectin expression. Although this is an animal model and the effects of the diets cannot be directly transposed to humans, this study provides indications of the possible adverse effects of FAS maternal diet on glucose metabolism in the offspring.

Genistein Precipitated Hypothyroidism, Altered Leptin and C-Reactive Protein Synthesis in Pregnant Rats

Genistein is an isoflavone constituent of soya. This study examined the mechanism by which genistein produced adverse effects in pregnant laboratory rats. Pregnant rats were divided into control (Con) and genistein (Gen) force fed (2 mg/kg) groups. At terminal gestation day (GD) ranging from 0-20, the rats were sacrificed, and blood samples and amniotic fluids were collected. Thyroid hormone, C-reactive protein (CRP) and leptin assay was carried using the blood samples. Leptin was also assayed in the placenta and amniotic fluid supernatant. Oral exposure of pregnant rats to genistein significantly altered maternal T3, (GD18; Con 1.65 ± 0.01, Gen 1.03 ± 0.04 nmol/L), T4 (GD6; Con 29.60 ± 0.00, Gen 36.04 ± 1.29 nmol/L), Leptin (Placenta GD20; Con 0.08 ± 0.01, Gen 0.31 ± 0.02 ng/ml, amniotic fluid ;GD 20; Con 0.02 ± 0.00, Gen 0.35 ± 0.05 ng/ml) in genistein group. These changes were accompanied with loss of embryonic implants and a decrease in fetal and placental weights. The CRP level was significantly decreased and increased at the onset and toward late pregnancy respectively. Oral exposure of pregnant rats to genistein precipitated hypothyroidism, altered some metabolic hormones with a reduction in fetal and placental growth and increased resorption of embryonic implants.

Changes in blood glucose, lipid profile and antioxidant activities in trained and untrained adult male subjects during programmed exercise on the treadmill

BACKGROUND

Exercise is a physical activity that maintains physical fitness and optimum health of an individual.

OBJECTIVE

The objective of this study was to determine changes in redox-oxidative status, lipid profile, cortisol, testosterone and fasting blood glucose (FBG) in trained and untrained male subjects during a programmed exercise session.

METHODS

Twenty (20) trained and twenty (20) untrained young healthy male subjects (age 21.75 +/- 1.15 years, height 1.74 +/- 0.02 m and weight 65.25 +/- 1.46 kg) participated in the study. Their weights, heights, waist and hip circumferences were measured. Subjects who have fasted for 12 hours exercised on the treadmill for 20 minutes at 1.5 km/hr after a warm-up period of exercising at 0.5 km/hr. for 3 minutes. Blood samples (1.5 ml) were withdrawn from the cubital vein before and immediately after the exercise session. Blood samples were analyzed for FBG, lipid profile, testosterone, cortisol and oxidative enzymes activities. Blood pressure and pulse rate were also measured before and after the exercise.

RESULTS

There was a significant decrease in rate of glucose disappearance in the trained subjects compared with the untrained subjects. The low density lipoprotein (bad cholesterol), TC, TC:HDL and LDL:HDL ratios were significantly higher in the untrained subjects both before and after the exercise while the trained subjects recorded significantly low cholesterol level. Testosterone and cortisol were significantly higher in untrained subjects before the exercise while its level balanced up with that of the trained subjects after the exercise. There was a significant increase in pulse pressure and diastolic pressure in untrained subjects after the exercise compared with trained subjects. Results of antioxidant assay showed that basal GPx and catalase were significantly higher in the trained subjects while GSH and SOD significantly increased in untrained subjects after the programmed exercise. Trained subjects expressed efficient energy utilization with better preparedness to handle oxidative stress better than untrained subjects.

CONCLUSION

Exercise improves body lipid profile, cardiovascular system and antioxidant status, thus providing better accommodative adjustment to changes without any significant change to blood pressure parameters during exposure to exercise training.

Acute oral toxicity test and phytochemistry of some West African medicinal plants

BACKGROUND

Although there is increased acceptance and utilization of medicinal plants worldwide, many are used indiscriminately without recourse to any safety test. Thus, the need for toxicity tests to determine the safe dose for oral consumption.

OBJECTIVE

LD50 and phytochemistry of four medicinal plants of West Africa were investigated.

METHODS

Thirty male and non pregnant female Swiss albino mice weighing 20grams each were used for this study. They were divided into the Control (C), Oldenlandia corymbosa L. aqueous leaf-extract treated (OCG), Parquetina nigrescens aqueous leaf extract treated (PNG), Hybanthus enneaspermus aqueous leaf extract treated (HEG), Ficus carica leaf extract treated (FCG) and Sesamum indicum aqueous seeds extract treated group (SIG). Each group except the control was further divided into four sub-groups of six mice each, and were administered orally, graded doses (SI; 1, 2, 4 and 8, PN; 2.5, 5, 10 and 20, OC; 5, 10, 20 and 40, FC; 1, 2, 4 and 8, HE; 4, 8, 16, 32) of the aqueous extract of each plant (g/kg body weight) after 12 hours fasting.

RESULTS

The dry aqueous leaf extracts of HE, OC, PN, FC all have dark brown colour and pH ranging from 6.1 to 7.2 while the seed extract of SI has a light brown color with pH of 7.0. Flavonoids, cardiac glycosides, anthocyanosides, saponin, and reducing sugar were present in all extracts, while cyanogenic glycoside was present only in HE. LD50 determination results obtained using Thompson and Finney methods were as follows; OC; 14.14 +/- 0.27 and 10.56 +/- 0.20, PN; 12.60 +/- 0.10 and 13.10 +/- 0.10, HE; 8.14 +/- 0.30 and 8.24 +/- 0.35, FC; 3.36 +/- 0.26 and 4.00 +/- 0.04, SI; 4.00 +/- 0.10 and 3.10 +/- 0.22 respectively (LD50 values are in g/kg body weight.

CONCLUSION

The results of this study have provided an oral LD50 from where a safe dose can be chosen for further research into the merits of the consumption of these medicinal plants.