Naguib Salleh

Leukemia Inhibitory Factor: Roles in Embryo Implantation and in Nonhormonal Contraception

Leukaemia inhibitory factor (LIF) plays an indispensible role in embryo implantation. Aberrant LIF production is linked to implantation failure. LIF regulates multiple processes prior to and during implantation such as uterine transformation into a receptive state, decidualization, blastocyst growth and development, embryo-endometrial interaction, trophoblast invasion, and immune modulation. Due to its critical role, LIF has been a target for a nonhormonal contraception. In this review, we summarize up-to-date information on the role of LIF in implantation and its role in contraception.

Quercetin ameliorates oxidative stress, inflammation and apoptosis in the heart of streptozotocin-nicotinamide-induced adult male diabetic rats

INTRODUCTION Quercetin is known to possess beneficial effects in ameliorating diabetic complications, however the mechanisms underlying cardioprotective effect of this compound in diabetes is not fully revealed. In this study, quercetin effect on oxidative stress, inflammation and apoptosis in the heart in diabetes were investigated. Normal and streptozotocin-nicotinamide induced adult male diabetic rats received quercetin (10, 25 and 50mg/kg/bw) orally for 28days were anesthetized and hemodynamic parameters i.e. systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were measured. Blood was collected for analyses of fasting glucose (FBG), insulin and cardiac injury marker levels (troponin-C, CK-MB and LDH). Following sacrificed, heart was harvested and histopathological changes were observed. Heart was subjected for analyses of oxidative stress marker i.e. lipid peroxidation and activity and expression levels of anti-oxidative enzymes i.e. SOD, CAT and GPx. Levels of inflammation in the heart were determined by measuring nuclear factor (p65-NF-κB), tumor necrosis factor (TNF-α), interleukins (IL)-1β and IL-6 levels by using enzyme-linked immunoassay (ELISA). Distribution and expression levels of TNF-α and Ikk-β (inflammatory markers), caspase-3, caspase-9, Blc-2 and Bax (apoptosis markers) in the heart were identified by immunohistochemistry and Western blotting respectively. RESULTS Administration of quercetin to diabetic rats caused significant decrease in FBG and cardiac injury marker levels with increased in insulin levels. In diabetic rat heart, lesser histopathological changes were observed with oxidative stress, inflammation and apoptosis levels markedly decreased. CONCLUSIONS Quercetin could potentially be used to ameliorate myocardial damage due to oxidative stress, inflammation and apoptosis in diabetes.

The effect of relaxin on the musculoskeletal system

Relaxin is a hormone structurally related to insulin and insulin‐like growth factor, which exerts its regulatory effect on the musculoskeletal and other systems through binding to its receptor in various tissues, mediated by different signaling pathways. Relaxin alters the properties of cartilage and tendon by activating collagenase. This hormone is also involved in bone remodeling and healing of injured ligaments and skeletal muscle. In this review, we have summarized the literature on the effect of relaxin in musculoskeletal system to provide a broad perspective for future studies in this field.

Sex-Steroid Regulation of Relaxin Receptor Isoforms (RXFP1 & RXFP2) Expression in the Patellar Tendon and Lateral Collateral Ligament of Female WKY Rats

The incidence of non-contact knee injury was found higher in female than in male and is related to the phases of the menstrual cycle. This raised the possibility that female sex-steroids are involved in the mechanism underlying this injury via affecting the expression of the receptors for relaxin, a peptide hormone known to modulate ligament laxity. Therefore, this study aims to investigate the effect of sex-steroids on relaxin receptor isoforms (RXFP1 & RXFP2) expression in the ligaments and tendons of the knee. Methods: Ovariectomized adult female WKY rats were treated with different doses of estrogen (0.2, 2, 20 μg/kg), progesterone (4mg) and testosterone (125 & 250μg/kg) for three consecutive days. At the end of the treatment, the animals were sacrificed and the patellar tendon and lateral collateral ligament were harvested for mRNA and protein expression analyses by Real Time PCR and Western blotting respectively. Results: RXFP1, the main isoform expressed in these knee structures and RXFP2 showed a dose-dependent increase in expression with estrogen. Progesterone treatment resulted in an increase while testosterone caused a dose-dependent decrease in the mRNA and protein expression of both relaxin receptor isoforms. Discussion: Progesterone and high dose estrogen up-regulate while testosterone down-regulates RXFP1 and RXFP2 expression in the patellar tendon and lateral collateral ligament of rats knee. Conclusion: Relaxin receptor isoforms up-regulation by progesterone and high dose estrogen could provide the basis for the reported increase in knee laxity while down-regulation of these receptor isoforms by testosterone could explain low incidence of non-contact knee injury in male.

In-vivo functional study on the involvement of CFTR, SLC26A6, NHE-1 and CA isoenzymes II and XII in uterine fluid pH, volume and electrolyte regulation in rats under different sex-steroid influence.

Precise control of uterine fluid pH, volume and electrolytes is important for the reproductive processes. In this study, we examined the functional involvement of multiple proteins including Cystic Fibrosis Transmembrane Regulator (CFTR), Cl-/HCO3- exchanger (SLC26A6), sodium-hydrogen exchanger-1 (NHE-1) and carbonic anhydrase (CA) in the regulation of these uterine fluid parameters. Methods: Adult female WKY rats were divided into intact, non-ovariectomised at different oestrous cycle phases and ovariectomised treated with sex-steroids. Following oestrous phase identification or sex-steroid treatment, in-vivo uterine perfusion was performed with and without the presence of these inhibitors: glibenclamide, DIDS, ACTZ and EIPA. The pH, volume, Cl-, HCO3- and Na+ concentrations of the perfusate from different groups were then analyzed. Meanwhile, the expression of CFTR, SLC26A6, NHE-1, CAII and CAXII was visualized by immunohistochemistry (IHC). Results: Parallel increase in the pH, volume, Cl-, HCO3- and Na+ concentrations was observed at estrus (Es), proestrus (Ps) and following 17β-oestradiol (E) treatment, which was inhibited by glibenclamide, DIDS and ACTZ while parallel reduction in these parameters was observed at diestrus (Ds) and following progesterone (P) treatment which was inhibited by ACTZ and EIPA. CFTR and SLC26A6 expression were up-regulated under E dominance, while NHE-1 expression was up-regulated under P dominance. Meanwhile, CA isoenzymes were expressed under both E and P influence. Conclusion: CFTR, SLC26A6 and CA were involved in mediating parallel increase in the uterine fluid volume, pH and electrolyte concentration under E while NHE and CA were involved in mediating the reduction of these parameters under P.

Isoflavone Genistein Induces Fluid Secretion and Morphological Changes in the Uteri of Post-Pubertal Rats

A reported increase in the incidence of infertility following high genistein intake could be related to alteration in the normal fluid volume and morphology of the uterus in adult female. In view of this, we investigated the effect of this compound on fluid secretion, fluid volume and morphology of the uterus in post-pubertal rats. Methods: Ovariectomised SD rats were treated with 17-β oestradiol (E) (0.8 X 10-4 mg/kg/day) and genistein (0.5, 5, 10, 25, 50 and 100 mg/kg/day) for three days. Following drug treatment, in-vivo uterine perfusion was performed and the rate of fluid secretion and the volume of fluid in the uterus were determined via changes in weight (μl/min) and F-dextran concentration of the perfusate respectively. The animals were then sacrificed and the uteri were removed for weight determination, morphological analyses and proliferative cell nuclear antigen (PCNA) expression analyses by Western blotting. Results: Subcutaneous genistein treatment resulted in a dose-dependent increase in fluid secretion rate, fluid volume and uterine wet weight. Treatment with 100 mg/kg/day genistein resulted in a remarkable increase in the rate of uterine fluid secretion, the volume of the uterine luminal fluid as well as the circumference of the uterine and uterine glandular lumen suggesting an excessive fluid accumulation. Meanwhile, there were evidence of glandular hyperplasia and an increase in the expression of PCNA following treatment with 50 and 100 mg/kg/day genistein. Conclusion: High genistein intake could potentially cause adverse effects on the uterus by inducing excessive fluid secretion and accumulation as well as hyperplasia.

Diverse roles of prostaglandins in blastocyst implantation.

Prostaglandins (PGs), derivatives of arachidonic acid, play an indispensable role in embryo implantation. PGs have been reported to participate in the increase in vascular permeability, stromal decidualization, blastocyst growth and development, leukocyte recruitment, embryo transport, trophoblast invasion, and extracellular matrix remodeling during implantation. Deranged PGs syntheses and actions will result in implantation failure. This review summarizes up-to-date literatures on the role of PGs in blastocyst implantation which could provide a broad perspective to guide further research in this field.

Vitis vinifera (Muscat Variety) Seed Ethanolic Extract Preserves Activity Levels of Enzymes and Histology of the Liver in Adult Male Rats with Diabetes

The effect of V. vinifera seeds on carbohydrate metabolizing enzymes and other enzymes of the liver in diabetes is currently unknown. We therefore investigated changes in the activity levels of these enzymes following V. vinifera seed extract administration to diabetic rats. Methods. V. vinifera seed ethanolic extract (250 and 500 mg/kg/day) or glibenclamide (600 μg/kg/day) was administered to streptozotocin-induced male diabetic rats for 28 consecutive days. At the end of treatment, liver was harvested and activity levels of various liver enzymes were determined. Levels of thiobarbituric acid reactive substances (TBARS) were measured in liver homogenates and liver histopathological changes were observed. Results. V. vinifera seed ethanolic extract was able to prevent the decrease in ICDH, SDH, MDH, and G-6-PDH and the increase in LDH activity levels in liver homogenates. The seed extract also caused serum levels of ALT, AST, ALP, ACP, GGT, and total bilirubin to decrease while causing total proteins to increase. Additionally, the levels of ALT, AST, and TBARS in liver homogenates were decreased. Histopathological changes in the liver were reduced. Conclusion. Near normal activity levels of various enzymes and histology of the liver following V. vinifera seed ethanolic extract administration may be due to decrease in liver oxidative stress in diabetes.

Genistein Induces Increase in Fluid pH, Na+ and HCO3- Concentration, SLC26A6 and SLC4A4 (NBCe1)-B Expression in the Uteri of Ovariectomized Rats

Genistein has been reported to stimulate luminal HCO3− secretion. We hypothesized that genistein mediates this effect via SLC26A6 and SLC4A4 (NBCe1) transporters. Our study aimed to: investigate changes in uterine fluid pH, Na+ and HCO3− concentration and expression of uterine SLC26A6 and NBCe1 under genistein effect. Ovariectomized adult female rats received 25, 50 and 100 mg/kg/day genistein for a week with and without ICI 182780. A day after the last injection, in vivo uterine perfusion was performed to collect uterine fluid for Na+, HCO3− and pH determination. The animals were then sacrificed and uteri were removed for mRNA and protein expression analyses. SLC26A6 and NBCe1-A and NBCe1-B distribution were visualized by immunohistochemistry (IHC). Genistein at 50 and 100 mg/kg/day stimulates uterine fluid pH, Na+ and HCO3− concentration increase. Genistein at 100 mg/kg/day up-regulates the expression of SLC26A6 and SLC4A4 mRNA, which were reduced following concomitant ICI 182780 administration. In parallel, SLC26A6 and NBCe1-B protein expression were also increased following high dose genistein treatment and were localized mainly at the apical membrane of the luminal epithelia. SLC26A6 and NBCe1-B up-regulation by genistein could be responsible for the observed increase in the uterine fluid pH, Na+ and HCO3− concentration under this condition.

Aqueous Extract of Phyllanthus niruri Leaves Displays In Vitro Antioxidant Activity and Prevents the Elevation of Oxidative Stress in the Kidney of Streptozotocin-Induced Diabetic Male Rats

P. niruri has been reported to possess antidiabetic and kidney protective effects. In the present study, the phytochemical constituents and in vitro antioxidant activity of P. niruri leaf aqueous extract were investigated together with its effect on oxidative stress and antioxidant enzymes levels in diabetic rat kidney. Results. Treatment of diabetic male rats with P. niruri leaf aqueous extract (200 and 400 mg/kg) for 28 consecutive days prevents the increase in the amount of lipid peroxidation (LPO) product, malondialdehyde (MDA), and the diminution of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activity levels in the kidney of diabetic rats. The amount of LPO showed strong negative correlation with SOD, CAT, and GPx activity levels. P. niruri leaf aqueous extract exhibits in vitro antioxidant activity with IC50 slightly lower than ascorbic acid. Phytochemical screening of plant extract indicates the presence of polyphenols. Conclusion. P. niruri leaf extract protects the kidney from oxidative stress induced by diabetes.