Changes in Expression and Function of Placental and Intestinal P-gp and BCRP Transporters during Pregnancy.

ABC transporters are ubiquitous in the human body and are responsible for the efflux of drugs. They are present in the placenta, intestine, liver and kidney, which are the major organs that can affect the pharmacokinetic and pharmacologic properties of drugs. P-gp and BCRP transporters are the best-characterized transporters in the ABC superfamily, and they have a pivotal role in the barrier tissues due to their efflux mechanism. Moreover, during pregnancy, drug efflux is even more important because of the developing fetus. Recent studies have shown that placental and intestinal ABC transporters have great importance in drug absorption and distribution. Placental and intestinal P-gp and BCRP show gestational-age-dependent expression changes, which determine the drug concentration both in the mother and the fetus during pregnancy. They may have an impact on the efficacy of antibiotic, antiviral, antihistamine, antiemetic and oral antidiabetic therapies. In this review, we would like to provide an overview of the pharmacokinetically relevant expression alterations of placental and intestinal ABC transporters during pregnancy.

Neurobehavioral impairments in ciprofloxacin- treated osteoarthritic adult rats.

Background and purpose:

Ciprofloxacin (CIP) is a broad-spectrum antibiotic widely used in clinical practice to treat musculoskeletal infections. Fluoroquinolone-induced neurotoxic adverse events have been reported in a few case reports, all the preclinical studies on its neuropsychiatric side effects involved only healthy animals. This study firstly investigated the behavioral effects of CIP in an osteoarthritis rat model with joint destruction and pain, which can simulate inflammation-associated musculoskeletal pain. Furthermore, effects of CIP on regional brain-derived neurotrophic factor (BDNF) expression were examined given its major contributions to the neuromodulation and plasticity underlying behavior and cognition. 

Fourteen days after induction of chronic osteoarthritis, animals were administered vehicle, 33 mg/kg or 100 mg/kg CIP for five days intraperitoneally. Motor activity, behavioral motivation, and psychomotor learning were examined in a reward-based behavioral test (Ambitus) on Day 4 and sensorimotor gating by the prepulse inhibition test on Day 5. Thereafter, the prolonged BDNF mRNA and protein expression levels were measured in the hippocampus and the prefrontal cortex. 

CIP dose-dependently reduced both locomotion and reward-motivated exploratory activity, accompanied with impaired learning ability. In contrast, there were no significant differences in startle reflex and sensory gating among treatment groups; however, CIP treatment reduced motor activity of the animals in this test, too. These alterations were associated with reduced BDNF mRNA and protein expression levels in the hippocampus but not the prefrontal cortex. 

This study revealed the detrimental effects of CIP treatment on locomotor activity and motivation/learning ability during osteoarthritic condition, which might be due to, at least partially, deficient hippocampal BDNF expression and ensuing impairments in neural and synaptic plasticity.

Physiological Cooperation between Aquaporin 5 and TRPV4.

Aquaporins-among them, AQP5-are responsible for transporting water across biological membranes, which is an important process in all living organisms. The transient receptor potential channel 4 (TRPV4) is a cation channel that is mostly calcium-permeable and can also be activated by osmotic stimuli. It plays a role in a number of different functions in the body, e.g., the development of bones and cartilage, and it is involved in the body's osmoregulation, the generation of certain types of sensation (pain), and apoptosis. Our earlier studies on the uterus and the literature data aroused our interest in the physiological role of the cooperation of AQP5 and TRPV4. In this review, we focus on the co-expression and cooperation of AQP5 and TRPV4 in the lung, salivary glands, uterus, adipose tissues, and lens. Understanding the cooperation between AQP5 and TRPV4 may contribute to the development of new drug candidates and the therapy of several disorders (e.g., preterm birth, cataract, ischemia/reperfusion-induced edema, exercise- or cold-induced asthma).

Immunofluorescent Evidence for Nuclear Localization of Aromatase in Astrocytes in the Rat Central Nervous System.

Estrogens regulate a variety of neuroendocrine, reproductive and also non-reproductive brain functions. Estradiol biosynthesis in the central nervous system (CNS) is catalyzed by the enzyme aromatase, which is expressed in several brain regions by neurons, astrocytes and microglia. In this study, we performed a complex fluorescent immunocytochemical analysis which revealed that aromatase is colocalized with the nuclear stain in glial fibrillary acidic protein (GFAP) positive astrocytes in cell cultures. Confocal immunofluorescent Z-stack scanning analysis confirmed the colocalization of aromatase with the nuclear DAPI signal. Nuclear aromatase was also detectable in the S100ß positive astrocyte subpopulation. When the nuclear aromatase signal was present, estrogen receptor alpha was also abundant in the nucleus. Immunostaining of frozen brain tissue sections showed that the nuclear colocalization of the enzyme in GFAP-positive astrocytes is also detectable in the adult rat brain. CD11b/c labelled microglial cells express aromatase, but the immunopositive signal was distributed only in the cytoplasm both in the ramified and amoeboid microglial forms. Immunostaining of rat ovarian tissue sections and human granulosa cells revealed that aromatase was present only in the cytoplasm. This novel observation suggests a new unique mechanism in astrocytes that may regulate certain CNS functions via estradiol production.

Fentanyl but Not Morphine or Buprenorphine Improves the Severity of Necrotizing Acute Pancreatitis in Rats.

Opioids are widely used for the pain management of acute pancreatitis (AP), but their impact on disease progression is unclear. Therefore, our aim was to study the effects of clinically relevant opioids on the severity of experimental AP. Various doses of fentanyl, morphine, or buprenorphine were administered as pre- and/or post-treatments in rats. Necrotizing AP was induced by the intraperitoneal injection of L-ornithine-HCl or intra-ductal injection of Na-taurocholate, while intraperitoneal caerulein administration caused edematous AP. Disease severity was determined by laboratory and histological measurements. Mu opioid receptor (MOR) expression and function was assessed in control and AP animals. MOR was expressed in both the pancreas and brain. The pancreatic expression and function of MOR were reduced in AP. Fentanyl post-treatment reduced necrotizing AP severity, whereas pre-treatment exacerbated it. Fentanyl did not affect the outcome of edematous AP. Morphine decreased vacuolization in edematous AP, while buprenorphine pre-treatment increased pancreatic edema during AP. The overall effects of morphine on disease severity were negligible. In conclusion, the type, dosing, administration route, and timing of opioid treatment can influence the effects of opioids on AP severity. Fentanyl post-treatment proved to be beneficial in AP. Clinical studies are needed to determine which opioids are best in AP.

A Hypercaloric Diet Induces Early Podocyte Damage in Aged, Non-Diabetic Rats.

BACKGROUND/AIMS: The number of patients of older age with metabolic syndrome, obesity, and associated kidney disease, which is characterized by podocyte damage, glomerular hypertrophy, and focal segmental glomerulosclerosis (FSGS), is increasing worldwide. Animal models that would reflect the development of such kidney diseases could facilitate the testing of drugs. We investigated the renal effects of a long-term high caloric diet in aged rats and the potential effects of drugs used to treat metabolic syndrome. METHODS: We analyzed nine-month-old male and female Sprague Dawley rats fed five months with a normal diet (control group) or high-fat-high-carbohydrate diet (HFHCD group). Two additional groups were fed with HFHCD and treated with drugs used in patients with metabolic syndrome, i.e., the glucagon-like peptide receptor 1 agonist liraglutide (HFHCD+liraglutide group) or metformin (HFHCD+metformin group). RESULTS: Except an increase of waist circumference as a sign of visceral obesity, the HFHCD diet did not induce metabolic syndrome or obesity. There were no significant changes in kidney function and all groups showed similar indices of glomerular injury, i.e., no differences in glomerular size or the number of glomeruli with FSGS or with FSGS-precursor lesions quantified by CD44 expression as a marker of parietal epithelial cell (PEC) activation. Analysis of ultrastructural morphology revealed mild podocyte stress and a decrease of glomerular nestin expression in the HFHCD group, whereas podocin and desmin were not altered. HFHCD did not promote fibrogenesis, however, treatment with liraglutide led to a slightly increased tubulointerstitial damage, immune cell infiltration, and collagen IV expression compared to the control and HFHCD groups. CONCLUSION: A five-month feeding with HFHCD in aged rats induced mild podocyte injury and microinflammation, which was not alleviated by liraglutide or metformin.

Sex differences in oxidative stress level and antioxidative enzymes expression and activity in obese pre-diabetic elderly rats treated with metformin or liraglutide.

AIM: To determine the effects of metformin or liraglutide on oxidative stress level and antioxidative enzymes gene expression and activity in the blood and vessels of pre-diabetic obese elderly Sprague-Dawley (SD) rats of both sexes. METHODS: Male and female SD rats were assigned to the following groups: a) control group (fed with standard rodent chow); b) high-fat and high-carbohydrate diet (HSHFD) group fed with HSHFD from 20-65 weeks of age; c) HSHFD+metformin treatment (50 mg/kg/d s.c.); and d) HSHFD+liraglutide treatment (0.3 mg/kg/d s.c). Oxidative stress parameters (ferric reducing ability of plasma and thiobarbituric acid reactive substances) and superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activity and gene expression were determined from serum, aortas, and surface brain blood vessels (BBV). RESULTS: HSHFD increased body weight in both sexes compared with the control group, while liraglutide prevented this increase. Blood glucose level did not change. The liraglutide group had a significantly increased antioxidative capacity compared with the HSHFD group in both sexes. The changes in antioxidative enzymes' activities in plasma were more pronounced in male groups. The changes in antioxidative gene expression were more prominent in microvessels and may be attributed to weight gain prevention. CONCLUSIONS: Obesity and antidiabetic drugs caused sex-related differences in the level of antioxidative parameters. Liraglutide exhibited stronger antioxidative effects than metformin. These results indicate that weight gain due to HSHFD is crucial for developing oxidative stress and for inhibiting antioxidative protective mechanisms.

Investigation of the Absorption of Nanosized lamotrigine Containing Nasal Powder via the Nasal Cavity.

Nasal drug delivery has become a popular research field in the last years. This is not surprising since the nose possesses unique anatomical and physical properties. Via the nasal mucosa local, systemic, and directly central nerve systemic (CNS) effect is achievable. Powders have favorable physicochemical properties over liquid formulations. Lamotrigine (LAM) is an antiepileptic agent with a relatively mild side effect spectrum, but only available in tablet form on market. Reducing the particle size to the nano range can affect the bioavailability of pharmaceutical products. The aim of this article was to continue the work started, compare the in vitro properties of a nanonized lamotrigine containing nasal powder (nanoLAMpowder) and its physical mixture (PM) that were prepared by dry milling. Moreover, to study their trans-epithelial absorption to reach the blood and target the brain by axonal transport. Due to the dry milling technique, the particle size of LAM, their surface and also their structure changed that led to higher in vitro dissolution and permeability rate. The results of the in vivo tests showed that the axonal transport of the drug was assumable by both intranasal formulations because the drug was present in the brain within a really short time, but the LAM from the nanoLAMpowder liberated even faster.

Obesity in pregnancy: a novel concept on the roles of adipokines in uterine contractility.

Obesity is a global health problem even among pregnant women. Obesity alters quality of labor, such as preterm labor, prolonged labor, and higher oxytocin requirements in pregnant women. The most important factors to play a role in the altered gestational period and serve as drug targets to treat the consequences are female sexual hormones, calcium channels, adrenergic system, oxytocin, and prostaglandins. However, we have limited information about the impact of obesity on the pregnant uterine contractility and gestation time. Adipose tissue, which is the largest endocrine and paracrine organ, especially in obesity, is responsible for the production of adipokines and various cytokines and chemokines, and there are no reliable data available describing the relation between body mass index, glucose intolerance, and adipokines during pregnancy. Recent data suggest that the dysregulation of leptin, adiponectin, and kisspeptin during pregnancy contributes to gestational diabetes mellitus and pre-eclampsia. A preclinical method for obese pregnancy should be developed to clarify the action of adipokines and assess their impact in obesity. The deeper understanding of the adipokines-induced processes in obese pregnancy may be a step closer to the prevention and therapy of preterm delivery or prolonged pregnancy. Gestational weight gain is one of the factors that could influence the prenatal development, birth weight, and adiposity of newborn.

Aquaporins during Pregnancy: Their Function and Significance.

Water is the major component of cells and tissues, and the movement of water across the cell membrane is a fundamental property of life. Until the discovery of the first water channel, aquaporin, it was long assumed that the transport of water was due to simple diffusion through the lipid bilayer membrane that encloses cells. Aquaporin (AQP) molecules were first discovered in the human uterus in 1994, and since then several studies have investigated these channels in the female reproductive system. The expressions of AQPs have been proven in the reproductive system. Their levels are altered during the implantation process, both in the uterus and the fetal cells, and participate in the control of the flow of amniotic fluid. They seem to be very important for the normal placental functions. AQPs are present during parturition, participating in the control of pregnant myometrial contractions and cervical ripening. However, most of the physiological and regulatory roles of AQPs are not clarified in the reproductive tract. Furthermore, no satisfactory knowledge is available about their sensitivities to different drugs. AQP-selective ligands may contribute to the development of new drug candidates and the therapy of several reproductive disorders.

The effects of progesterone on the alpha2-adrenergic receptor subtypes in late-pregnant uterine contractions in vitro.

BACKGROUND: The adrenergic system and progesterone play major roles in the control of the uterine function. Our aims were to clarify the changes in function and expression of the α2-adrenergic receptor (AR) subtypes after progesterone pretreatment in late pregnancy. METHODS: Sprague Dawley rats from pregnancy day 15 were treated with progesterone for 7 days. The myometrial expressions of the α2-AR subtypes were determined by RT-PCR and Western blot analysis. In vitro contractions were stimulated with (-)-noradrenaline, and its effect was modified with the selective antagonists BRL 44408 (α2A), ARC 239 (α2B/C) and spiroxatrine (α2A). The accumulation of myometrial cAMP was also measured. The activated G-protein level was investigated via GTPγS binding assays. RESULTS: Progesterone pretreatment decreased the contractile effect of (-)-noradrenaline through the α2-ARs. The most significant reduction was found through the α2B-ARs. The mRNA of all of the α2-AR subtypes was increased. Progesterone pretreatment increased the myometrial cAMP level in the presence of BRL 44408 (p < 0.001), spiroxatrine (p < 0.001) or the spiroxatrine + BRL 44408 combination (p < 0.05). Progesterone pretreatment increased the G-protein-activating effect of (-)-noradrenaline in the presence of the spiroxatrine + BRL 44408 combination. CONCLUSIONS: The expression of the α2-AR subtypes is progesterone-sensitive. It decreases the contractile response of (-)-noradrenaline through the α2B-AR subtype, blocks the function of α2A-AR subtype and alters the G protein coupling of these receptors, promoting a Gs-dependent pathway. A combination of α2C-AR agonists and α2B-AR antagonists with progesterone could be considered for the treatment or prevention of preterm birth.

The effects of estrogen on the α2-adrenergic receptor subtypes in rat uterine function in late pregnancy in vitro.

AIM: To assess the effect of 17ß-estradiol pretreatment on the function and expression of α2- adrenergic receptors (ARs) subtypes in late pregnancy in rats. METHODS: Sprague-Dawley rats (n=37) were treated with 17ß-estradiol for 4 days starting from the 18th day of pregnancy. The myometrial expression of the α2-AR subtypes was determined by real time polymerase chain reaction and Western blot analysis. In vitro contractions were stimulated with (-)-noradrenaline, and its effect was modified with the selective antagonists BRL 44408 (α2A), ARC 239 (α2B/C), and spiroxatrine (α2A). The cyclic adenosine monophosphate (cAMP) accumulation was also measured. The activated G-protein level was investigated by guanosine 5'-O-[gamma-thio]triphosphate (GTPγS) binding assay. RESULTS: 17ß-estradiol pretreatment decreased the contractile effect of (-)-noradrenaline via the α2-ARs, and abolished the contractile effect via the α2B-ARs. All the α2-AR subtypes' mRNA was significantly decreased. 17ß-estradiol pretreatment significantly increased the myometrial cAMP level in the presence of BRL 44408 (P=0.001), ARC 239 (P=0.007), and spiroxatrine (P=0.045), but did not modify it in the presence of spiroxatrine + BRL 44408 combination (P=0.073). It also inhibited the G-protein-activating effect of (-)-noradrenaline by 25% in the presence of BRL 44408 + spiroxatrine combination. CONCLUSIONS: The expression of the α2-AR subtypes is sensitive to 17ß-estradiol, which decreases the contractile response of (-)-noradrenaline via the α2B-AR subtype, and might cause changes in G-protein signaling pathway. Estrogen dysregulation may be responsible for preterm labor or uterine inertia via the α2-ARs.

The Effects of Female Sexual Hormones on the Expression of Aquaporin 5 in the Late-Pregnant Rat Uterus.

Thirteen mammalian aquaporin (AQP) water channels are known, and few of them play a role in the mammalian reproductive system. In our earlier study, the predominance of AQP5 in the late-pregnant rat uterus was proven. Our current aim was to investigate the effect of estrogen- and gestagen-related compounds on the expression of the AQP5 channel in the late-pregnant rat uterus. Furthermore, we examined the effect of hormonally-induced preterm delivery on the expression of AQP5 in the uterus. We treated pregnant Sprague-Dawley rats subcutaneously with 17ß-estradiol, clomiphene citrate, tamoxifen citrate, progesterone, levonorgestrel, and medroxyprogesterone acetate. Preterm delivery was induced by subcutaneous mifepristone and intravaginal prostaglandin E2. Reverse-transcriptase PCR and Western blot techniques were used for the detection of the changes in AQP5 mRNA and protein expressions. The amount of AQP5 significantly increased after progesterone and progesterone analogs treatment on 18 and 22 days of pregnancy. The 17ß-estradiol and estrogen receptor agonists did not influence the AQP5 mRNA level; however, estradiol induced a significant increase in the AQP5 protein level on the investigated days of gestation. Tamoxifen increased the AQP5 protein expression on day 18, while clomiphene citrate was ineffective. The hormonally-induced preterm birth significantly decreased the AQP5 level similarly to the day of delivery. We proved that AQP5 expression is influenced by both estrogen and progesterone in the late-pregnant rat uterus. The influence of progesterone on AQP5 expression is more predominant as compared with estrogen.

Oxytocin regulates the expression of aquaporin 5 in the late-pregnant rat uterus.

Aquaporins (AQPs) are integral membrane channels responsible for the transport of water across a cell membrane. Based on reports that AQPs are present and accumulate in the female reproductive tract late in pregnancy, our aim was to study the expression of AQP isoforms (AQP1, 2, 3, 5, 8, and 9) at the end of pregnancy in rat in order to determine if they play a role in parturition. Reverse-transcriptase PCR revealed that specific Aqp mRNAs were detectable in the myometrium of non-pregnant and late-pregnancy (Days 18, 20, 21, and 22 of pregnancy) rat uteri. The expression of Aqp5 mRNA and protein were most pronounced on Days 18-21, and were dramatically decreased on Day 22 of pregnancy. In contrast, a significant increase was found in the level of Aqp5 transcript in whole-blood samples on the last day of pregnancy. The effect of oxytocin on myometrial Aqp5 expression in an organ bath was also investigated. The level of Aqp5 mRNA significantly decreased 5 min after oxytocin (10(-8) M) administration, similarly to its profile on the day of delivery; this effect was sensitive to the oxytocin antagonist atosiban. The vasopressin analog desmopressin (3.7 × 10(-8) M), on the other hand, did not alter the expression of Aqp5, but did increased the amount of Aqp2 mRNA, an effect that was atosiban-resistant. These results lead us to propose that oxytocin selectively influences the expression of Aqp5 at the end of pregnancy, and may participate in events that lead to parturition in the rat. The sudden increase of AQP5 in the blood on the last day of pregnancy may serve as a marker that indicates the initiation of delivery.

[Investigation of gestagenic effect of raw drone milk in rats]. / A nyers heretej gesztagén hatásainak vizsgálata patkányban.

Numerous honeybee products are used in traditional medicine. The best-known honeybee products are the honey, the propolis and the royal jelly. Drone milk is a relatively little-known honeybee product. Although, drone milk is traditionally used to treat infertility and to promote vitality in both men and women in certain countries, the literature furnishes no information concerning effects of the drone milk. The oestrogenic and androgenic effects of drone milk have recently been reported in rats and the effective compounds have also been identified. The aim of this study was to determine the putative gestagenic effect of raw drone milk in rats. Maintenance of pregnancy assays revealed that drone milk was able to increase the number of surviving fetuses. This results suggested some gestagenic effects. This effect was confirmed by RT-PCR and Western blot methods in which the mRNA and protein expressions of gestagen-dependent CRLR (Calcitonin Receptor-Like Receptor) peptide were determined. To determine the efficacy of gestagenic effect of drone milk, spironolactone (weak gestagen compound) was used. The combination of drone milk and spironolactone showed more potent gestagenic effect. These results lead us to suppose that raw drone milk shows weak gestagenic effect and this effect can be increased by another weak gestagen. Further studies are required to clarify the gestagenic mechanisms of action of drone milk.

[The effect of R(+) limonene on ß - adrenerg signaling: the significance of oxidative stress index]. / R(+)limonén hatása a ß-adrenerg jelátvitelre a simaizomzatban: az oxidatív stressz index jelentosége.

Reactive oxygen intermediers (ROI) play a role in the signal transduction of beta-adrenergic receptors. We investigated whether an antioxidant (limonene) can reduce the beta-mimetic effect of terbutaline in beta-2-adrenergic receptor (ß2-AR)-regulated smooth muscles. Tissue samples were collected from nonpregnant (trachea) and 22-day-pregnant (myometrium and cervix) rats. Tissue contractility was investigated in an isolated organ bath. In separate groups of animals, the tracheal and uterine ß2-AR activities were upregulated by 17-beta-estradiol valerate (E2) and progesterone (P4), respectively. The total oxidant (TOS) and total antioxidant status (TAS) were also measured. The oxidative stress index (OSI) was defined as the ratio ofTOS and TAS. Terbutaline (10(-10) - 10(-5) M) decreased the spontaneous contractions in the nontreated and the P4-pretreated myometria. The concentration-response curves for terbutaline in the presence of 10-3 M limonene were shifted to the left, but the maximum inhibitory effect was unchanged. Terbutaline (10(-6) M) increased the cervical resistance both in the nontreated and in the P4-treated samples, while limonene reduced this action only in the P4-treated cervices. Terbutaline (10(-9) - 10(-4) M) reduced the tracheal tones both in the nontreated and in the E2-treated tissues, while limonene reduced these effects. The OSI was highest in the trachea and lowest in the pregnant myometrium. Limonene has various influence on terbutaline induced effects in certain tissues. Higher OSI value means, that the antioxidants have greater role in the beta-adrenergic signalmechanism. We assume that the significance of ROI in the signalling process of the ß2-ARs are divergent in the various tissues. Our results suggest that the antiasthmatic effect of beta-mimetics may worsen during parallel limonene administration.

[The effect of R(+) limonene on ß-adrenergic signaling in smooth muscles: the significance of oxidative stress index]. / R(+)limonén hatása a ß-adrenerg jelátvitelre a simaizomzatban: az oxidatív stressz index jelentosége.

Reactive oxygen intermediers (ROI) play a role in the signal transduction of beta-adrenergic receptors. We investigated whether an antioxidant (limonene) can reduce the beta-mimetic effect of terbutaline in beta-2-adrenergic receptor (ß2-AR)-regulated smooth muscles. Tissue samples were collected from nonpregnant (trachea) and 22-day-pregnant (myometrium and cervix) rats. Tissue contractility was investigated in an isolated organ bath. In separate groups of animals, the tracheal and uterine ß2-AR activities were upregulated by 17-beta-estradiol valerate (E2) and progesterone (P4), respectively. The total oxidant (TOS) and total antioxidant status (TAS) were also measured. The oxidative stress index (OSI) was defined as the ratio ofTOS and TAS. Terbutaline (10(-10) - 10(-5) M) decreased the spontaneous contractions in the nontreated and the P4-pretreated myometria. The concentration-response curves for terbutaline in the presence of 10-3 M limonene were shifted to the left, but the maximum inhibitory effect was unchanged. Terbutaline (10(-6) M) increased the cervical resistance both in the nontreated and in the P4-treated samples, while limonene reduced this action only in the P4-treated cervices. Terbutaline (10(-9) - 10(-4) M) reduced the tracheal tones both in the nontreated and in the E2-treated tissues, while limonene reduced these effects. The OSI was highest in the trachea and lowest in the pregnant myometrium. Limonene has various influence on terbutaline induced effects in certain tissues. Higher OSI value means, that the antioxidants have greater role in the beta-adrenergic signalmechanism. We assume that the significance of ROI in the signalling process of the ß2-ARs are divergent in the various tissues. Our results suggest that the antiasthmatic effect of beta-mimetics may worsen during parallel limonene administration.

Uterus-relaxing effect of ß2-agonists in combination with phosphodiesterase inhibitors: studies on pregnant rat in vivo and on pregnant human myometrium in vitro.

AIMS: Our aims were to examine the effects of a simultaneous stimulation of ß(2) -adrenergic receptors and inhibition of uterine phosphodiesterases (PDE), in the pregnant rat uterus in vivo and on human uterine tissue in vitro. We also set out to measure cAMP levels and detect the expressions of the isoenzymes PDE4B and PDE4D in human uterine tissue samples. MATERIAL AND METHODS: Preterm birth was induced in Sprague-Dawley rats with bacterial lipopolysaccharide. The uterine effects of terbutaline alone or in combination with rolipram were tested in vivo. Human myometrial strips from cesarean sections at full-term pregnancy and at preterm labor were stimulated with oxytocin, and the inhibitory effects of theophylline, rolipram and terbutaline were studied. The myometrial accumulation of cAMP in the presence of rolipram and terbutaline was determined by enzyme immunoassay. The expressions of PDE4B and PDE4D proteins were detected by Western blotting. RESULTS: The selective PDE4 inhibitor rolipram was more effective than the non-selective PDE inhibitor theophylline in inhibiting the oxytocin-induced contractions in the human uterus. The uterus-relaxing effects of low doses of terbutaline were markedly potentiated by rolipram, both in rats and in human tissues. The changes in uterine cAMP levels correlated with these results. At preterm labor, PDE4B was the predominant form of PDE4 expressed; at full term, PDE4D was expressed more strongly. CONCLUSIONS: A combination of selective PDE4 inhibitors and ß(2) -agonists should be considered for the treatment of preterm contractions.

Soluplus® promotes efficient transport of meloxicam to the central nervous system via nasal administration.

In our present series of experiments, we investigated the nasal applicability of the previously developed Soluplus® - meloxicam polymeric micelle formulation. Utilizing the nasal drug investigations, moderately high mucoadhesion was experienced in nasal conditions which alongside the appropriate physicochemical properties in liquid state, contributed to rapid drug absorption through human RPMI 2650 cell line. Ex vivo studies also confirmed that higher nasal mucosal permeation could be expected with the polymeric micelle nanoformulation compared to a regular MEL suspension. Also, the nanoformulation met the requirements to provide rapid drug permeation in less 1 h of our measurement. The non-toxic, non-cell barrier damaging formulation also proved to provide a successful passive transport across excides human nasal mucosa. Based on our in vivo investigations, it can be concluded that the polymeric micelle formulation provides higher meloxicam transport to the central nervous system followed by a slow and long-lasting elimination process compared to prior results where physical particle size reduction methods were applied. With these results, a promising solution and nanocarrier is proposed for the successful transport of non-steroidal anti-inflammatory drugs with acidic character to the brain.

Elderly rats fed with a high-fat high-sucrose diet developed sex-dependent metabolic syndrome regardless of long-term metformin and liraglutide treatment.

Aim/Introduction: The study aimed to determine the effectiveness of early antidiabetic therapy in reversing metabolic changes caused by high-fat and high-sucrose diet (HFHSD) in both sexes. Methods: Elderly Sprague-Dawley rats, 45 weeks old, were randomized into four groups: a control group fed on the standard diet (STD), one group fed the HFHSD, and two groups fed the HFHSD along with long-term treatment of either metformin (HFHSD+M) or liraglutide (HFHSD+L). Antidiabetic treatment started 5 weeks after the introduction of the diet and lasted 13 weeks until the animals were 64 weeks old. Results: Unexpectedly, HFHSD-fed animals did not gain weight but underwent significant metabolic changes. Both antidiabetic treatments produced sex-specific effects, but neither prevented the onset of prediabetes nor diabetes. Conclusion: Liraglutide vested benefits to liver and skeletal muscle tissue in males but induced signs of insulin resistance in females.