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1.
Sci Rep ; 14(1): 10190, 2024 05 03.
Article in English | MEDLINE | ID: mdl-38702366

ABSTRACT

Dysfunction of central serotonergic neurons is known to cause depressive disorders in humans, who often show reproductive and/or glucose metabolism disorders. This study examined whether dorsal raphe (DR) serotonergic neurons sense high glucose availability to upregulate reproductive function via activating hypothalamic arcuate (ARC) kisspeptin neurons (= KNDy neurons), a dominant stimulator of gonadotropin-releasing hormone (GnRH)/gonadotropin pulses, using female rats and goats. RNA-seq and histological analysis revealed that stimulatory serotonin-2C receptor (5HT2CR) was mainly expressed in the KNDy neurons in female rats. The serotonergic reuptake inhibitor administration into the mediobasal hypothalamus (MBH), including the ARC, significantly blocked glucoprivic suppression of luteinizing hormone (LH) pulses and hyperglycemia induced by intravenous 2-deoxy-D-glucose (2DG) administration in female rats. A local infusion of glucose into the DR significantly increased in vivo serotonin release in the MBH and partly restored LH pulses and hyperglycemia in the 2DG-treated female rats. Furthermore, central administration of serotonin or a 5HT2CR agonist immediately evoked GnRH pulse generator activity, and central 5HT2CR antagonism blocked the serotonin-induced facilitation of GnRH pulse generator activity in ovariectomized goats. These results suggest that DR serotonergic neurons sense high glucose availability to reduce gluconeogenesis and upregulate reproductive function by activating GnRH/LH pulse generator activity in mammals.


Subject(s)
Glucose , Goats , Gonadotropin-Releasing Hormone , Luteinizing Hormone , Receptor, Serotonin, 5-HT2C , Serotonergic Neurons , Animals , Luteinizing Hormone/metabolism , Female , Receptor, Serotonin, 5-HT2C/metabolism , Rats , Serotonergic Neurons/metabolism , Gonadotropin-Releasing Hormone/metabolism , Glucose/metabolism , Serotonin/metabolism , Kisspeptins/metabolism , Arcuate Nucleus of Hypothalamus/metabolism , Arcuate Nucleus of Hypothalamus/drug effects , Dorsal Raphe Nucleus/metabolism , Dorsal Raphe Nucleus/drug effects , Rats, Sprague-Dawley
2.
Endocrinology ; 165(4)2024 Feb 20.
Article in English | MEDLINE | ID: mdl-38470466

ABSTRACT

The neuroendocrine system that controls the preovulatory surge of gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH), which triggers ovulation in female mammals, is sexually differentiated in rodents. A transient increase in circulating testosterone levels in male rats within a few hours of birth is primarily responsible for the defeminization of anteroventral periventricular nucleus (AVPV) kisspeptin neurons, which are critical regulators of the GnRH/LH surge. The present study aimed to determine whether neonatal estradiol-17ß (E2) converted from testosterone by aromatase primarily causes the defeminization of AVPV kisspeptin neurons and the surge of GnRH/LH in male rodents. The results of the present study showed that the neonatal administration of letrozole (LET), a nonsteroidal aromatase inhibitor, within 2 hours of birth rescued AVPV Kiss1 expression and the LH surge in adult male rats, while the neonatal administration of testosterone propionate (TP) irreversibly attenuated AVPV Kiss1 expression and the LH surge in adult female rats. Furthermore, the neonatal LET-treated Kiss1-Cre-activated tdTomato reporter males exhibited a comparable number of AVPV Kiss1-Cre-activated tdTomato-expressing cells to that of vehicle-treated female rats, while neonatal TP-treated females showed fewer AVPV Kiss1-Cre-activated tdTomato-expressing cells than vehicle-treated females. Moreover, neonatal TP administration significantly decreased the number of arcuate Kiss1-expressing and Kiss1-Cre-activated tdTomato-positive cells and suppressed LH pulses in adult gonadectomized female rats; however, neonatal LET administration failed to affect them. These results suggest that E2 converted from neonatal testosterone is primarily responsible for the defeminization of AVPV kisspeptin neurons and the subsequent GnRH/LH surge generation in male rats.


Subject(s)
Aromatase , Kisspeptins , Red Fluorescent Protein , Animals , Female , Male , Rats , Aromatase/metabolism , Estradiol/metabolism , Gonadotropin-Releasing Hormone/metabolism , Hypothalamus, Anterior/metabolism , Kisspeptins/genetics , Kisspeptins/metabolism , Luteinizing Hormone/metabolism , Mammals/metabolism , Neurons/metabolism , Testosterone/metabolism
3.
Sci Rep ; 13(1): 20495, 2023 11 22.
Article in English | MEDLINE | ID: mdl-37993510

ABSTRACT

The gonadotropin-releasing hormone (GnRH) pulse and surge are considered to be generated by arcuate kisspeptin/neurokinin B/dynorphin A (KNDy) neurons and anteroventral periventricular nucleus (AVPV) kisspeptin neurons, respectively, in female rodents. The majority of KNDy and AVPV kisspeptin neurons express κ-opioid receptors (KORs, encoded by Oprk1) in female rodents. Thus, this study aimed to investigate the effect of a conditional Oprk1-dependent Kiss1 deletion in kisspeptin neurons on the luteinizing hormone (LH) pulse/surge and fertility using Kiss1-floxed/Oprk1-Cre rats, in which Kiss1 was deleted in cells expressing or once expressed the Oprk1/Cre. The Kiss1-floxed/Oprk1-Cre female rats, with Kiss1 deleted in a majority of KNDy neurons, showed normal puberty while having a one-day longer estrous cycle and fewer pups than Kiss1-floxed controls. Notably, ovariectomized (OVX) Kiss1-floxed/Oprk1-Cre rats showed profound disruption of LH pulses in the presence of a diestrous level of estrogen but showed apparent LH pulses without estrogen treatment. Furthermore, Kiss1-floxed/Oprk1-Cre rats, with Kiss1 deleted in approximately half of AVPV kisspeptin neurons, showed a lower peak of the estrogen-induced LH surge than controls. These results suggest that arcuate and AVPV kisspeptin neurons expressing or having expressed Oprk1 have a role in maintaining normal GnRH pulse and surge generation, the normal length of the estrous cycle, and the normal offspring number in female rats.


Subject(s)
Kisspeptins , Luteinizing Hormone , Rats , Female , Animals , Kisspeptins/metabolism , Luteinizing Hormone/pharmacology , Estrogens/pharmacology , Gonadotropin-Releasing Hormone/metabolism , Neurokinin B/genetics , Neurokinin B/metabolism , Dynorphins/metabolism , Neurons/metabolism , Arcuate Nucleus of Hypothalamus/metabolism
4.
J Reprod Dev ; 69(5): 227-238, 2023 Oct 20.
Article in English | MEDLINE | ID: mdl-37518187

ABSTRACT

Hypothalamic kisspeptin neurons are master regulators of mammalian reproduction via direct stimulation of gonadotropin-releasing hormone and consequent gonadotropin release. Here, we generated novel Kiss1 (kisspeptin gene)-Cre rats and investigated the developmental changes and sex differences in visualized Kiss1 neurons of Kiss1-Cre-activated tdTomato reporter rats. First, we validated Kiss1-Cre rats by generating Kiss1-expressing cell-specific Kiss1 knockout (Kiss1-KpKO) rats, which were obtained by crossing the current Kiss1-Cre rats with Kiss1-floxed rats. The resulting male Kiss1-KpKO rats lacked Kiss1 expression in the brain and exhibited hypogonadotropic hypogonadism, similar to the hypogonadal phenotype of global Kiss1 KO rats. Histological analysis of Kiss1 neurons in Kiss1-Cre-activated tdTomato reporter rats revealed that tdTomato signals in the anteroventral periventricular nucleus (AVPV) and arcuate nucleus (ARC) were not affected by estrogen, and that tdTomato signals in the ARC, AVPV, and medial amygdala (MeA) were sexually dimorphic. Notably, neonatal AVPV tdTomato signals were detected only in males, but a larger number of tdTomato-expressing cells were detected in the AVPV and ARC, and a smaller number of cells in the MeA was detected in females than in males at postpuberty. These findings suggest that Kiss1-visualized rats can be used to examine the effect of estrogen feedback mechanisms on Kiss1 expression in the AVPV and ARC. Moreover, the Kiss1-Cre and Kiss1-visualized rats could be valuable tools for further detailed analyses of sexual differentiation in the brain and the physiological role of kisspeptin neurons across the brain in rats.


Subject(s)
Kisspeptins , Sex Characteristics , Rats , Animals , Female , Male , Kisspeptins/metabolism , Arcuate Nucleus of Hypothalamus/metabolism , Estrogens/metabolism , Neurons/metabolism , Mammals/metabolism
5.
J Neurosci ; 43(12): 2140-2152, 2023 03 22.
Article in English | MEDLINE | ID: mdl-36813577

ABSTRACT

Ovulation disorders are a serious problem for humans and livestock. In female rodents, kisspeptin neurons in the anteroventral periventricular nucleus (AVPV) are responsible for generating a luteinizing hormone (LH) surge and consequent ovulation. Here, we report that adenosine 5-triphosphate (ATP), a purinergic receptor ligand, is a possible neurotransmitter that stimulates AVPV kisspeptin neurons to induce an LH surge and consequent ovulation in rodents. Administration of an ATP receptor antagonist (PPADS) into the AVPV blocked the LH surge in ovariectomized (OVX) rats treated with a proestrous level of estrogen (OVX + high E2) and significantly reduced the ovulation rate in proestrous ovary-intact rats. AVPV ATP administration induced a surge-like LH increase in OVX + high E2 rats in the morning. Importantly, AVPV ATP administration could not induce the LH increase in Kiss1 KO rats. Furthermore, ATP significantly increased intracellular Ca2+ levels in immortalized kisspeptin neuronal cell line, and coadministration of PPADS blocked the ATP-induced Ca2+ increase. Histologic analysis revealed that the proestrous level of estrogen significantly increased the number of P2X2 receptor (an ATP receptor)-immunopositive AVPV kisspeptin neurons visualized by tdTomato in Kiss1-tdTomato rats. The proestrous level of estrogen significantly increased varicosity-like vesicular nucleotide transporter (a purinergic marker)-immunopositive fibers projecting to the vicinity of AVPV kisspeptin neurons. Furthermore, we found that some hindbrain vesicular nucleotide transporter-positive neurons projected to the AVPV and expressed estrogen receptor α, and the neurons were activated by the high E2 treatment. These results suggest that hindbrain ATP-purinergic signaling triggers ovulation via activation of AVPV kisspeptin neurons.SIGNIFICANCE STATEMENT Ovulation disorders, which cause infertility and low pregnancy rates, are a serious problem for humans and livestock. The present study provides evidence that adenosine 5-triphosphate, acting as a neurotransmitter in the brain, stimulates kisspeptin neurons in the anteroventral periventricular nucleus, known as the gonadotropin-releasing hormone surge generator, via purinergic receptors to induce the gonadotropin-releasing hormone/luteinizing hormone surge and ovulation in rats. In addition, histologic analyses indicate that adenosine 5-triphosphate is likely to be originated from the purinergic neurons in the A1 and A2 of the hindbrain. These findings may contribute to new therapeutic controls for hypothalamic ovulation disorders in humans and livestock.


Subject(s)
Kisspeptins , Receptors, Purinergic P2 , Humans , Rats , Female , Animals , Kisspeptins/metabolism , Estradiol/pharmacology , Estradiol/metabolism , Luteinizing Hormone/metabolism , Hypothalamus, Anterior/metabolism , Gonadotropin-Releasing Hormone/metabolism , Estrogens/pharmacology , Estrogens/metabolism , Neurons/metabolism , Ovulation , Rhombencephalon/metabolism , Adenosine Triphosphate/metabolism , Nucleotides/metabolism , Nucleotides/pharmacology , Adenosine/metabolism
6.
J Sports Sci ; 41(24): 2209-2228, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38390833

ABSTRACT

This study investigated the effect of an 8-week neuromuscular electrical stimulation (NMES) training programme (3 days/week) on muscle quantity and quality and single-joint performance in the knee extensors. Thirty-nine untrained young male participants were randomly assigned to NMES training (n = 21) and control (n = 18) groups. The 8-week NMES training induced significant increase in the isometric maximal voluntary contraction (MVC) torque of the knee extensors (≈9.3%), muscle volume of the individual and entire quadriceps muscles determined by magnetic resonance imaging (≈3.3%-6.4%), and a significant decrease in the ultrasound echo intensity of the vastus lateralis (≈-4.0%); however, hypertrophy of the vastus intermedius (i.e., the deep muscle) was limited (≈3.3%). In the NMES training group, the repeated measures correlations of the isometric MVC torque with the muscle volume of the entire quadriceps muscle and each quadriceps muscle were significant (rrm (20) = 0.551-0.776), whereas that of the isometric MVC torque with the ultrasound echo intensity of the vastus lateralis was not significant. These findings suggest that NMES training produces muscle strength gains, muscle hypertrophy, and partial muscle quality improvement and that the NMES training-induced muscle strength gains is caused by muscle hypertrophy in the knee extensors.


Subject(s)
Quadriceps Muscle , Quality Improvement , Humans , Male , Electric Stimulation , Quadriceps Muscle/diagnostic imaging , Quadriceps Muscle/physiology , Muscle Strength/physiology , Isometric Contraction/physiology , Torque , Hypertrophy , Muscle, Skeletal/diagnostic imaging , Muscle, Skeletal/physiology
7.
Org Lett ; 24(36): 6594-6598, 2022 09 16.
Article in English | MEDLINE | ID: mdl-36053018

ABSTRACT

A one-pot catalytic synthesis of α-tetrasubstituted amino acid derivatives via in situ generation of N-unsubstituted ketimines is reported. Because of the irreversible formation of N-unsubstituted ketimines, the yields were higher than those generated under the conventional one-pot reaction conditions. This process prevents the need to isolate unstable N-unsubstituted ketimines with alkyl substituents and streamlines the synthesis of highly congested α-amino acid derivatives.


Subject(s)
Imines , Nitriles , Amino Acids/chemistry , Imines/chemistry , Nitriles/chemistry , Stereoisomerism
9.
Medicina (Kaunas) ; 58(2)2022 Feb 15.
Article in English | MEDLINE | ID: mdl-35208616

ABSTRACT

Background and Objectives: The antidiabetic agent metformin is known to activate AMP-activated protein kinase (AMPK) in various tissues. Because AMPK can modulate intracellular circadian clocks through regulating the stability of clock components, a single dose of metformin has been reported to affect circadian clocks in the peripheral tissues. In this study, therefore, we investigated whether chronic treatment with metformin causes the impairment of circadian clocks, especially if given at an inappropriate time. Materials and Methods: Non-diabetic C57BL/6J mice were allowed access to food only during 4 h at the beginning of the dark period, and repeatedly i.p. injected with a nearly maximum non-toxic dose of metformin, once daily either at 4 h after the beginning of the dark period or at the beginning of the light period. Diabetic ob/ob mice were given free access to food and treated with metformin in drinking water. Results: Under the controlled feeding regimen, 8-day treatment with metformin did not alter the mRNA expression rhythms of clock genes in both liver and adipose tissue of C57BL/6J mice, regardless of dosing time. In addition, chronic treatment with metformin for 2 weeks affected hepatic AMPK activation rhythm but did not disrupt the circadian clocks in the liver and adipose tissues of the ob/ob mice. Conclusions: These results mitigate concerns that treatment with metformin impairs peripheral circadian clocks, although confirmation is needed in humans.


Subject(s)
Circadian Clocks , Metformin , Animals , Circadian Clocks/genetics , Circadian Rhythm/physiology , Liver , Mice , Mice, Inbred C57BL
10.
Phys Rev E ; 104(2-2): 025111, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34525522

ABSTRACT

We conducted numerical experiments to investigate the mixing of stratified suspensions containing different types of particles. We used a point-force two-way coupling method. We studied the mixing behavior of stratified suspensions and we discovered two types of mixing: microscopic (individual-particle-level) and macroscopic (vessel-scale) collective mixing. In addition, we examined the vertical mixing speed of the stratified suspension. We used a simple theoretical model to analyze the fingering settling velocity. Then we introduced a nondimensional number representing the difference in collectivities of the upper and lower suspensions while accounting for particle terminal velocities. We discovered that the proposed nondimensional parameter has a negative sign that distinguishes the mixing form of only microscopic individual-particle-level mixing and a positive value that predicts the speed of macroscopic collective mixing of stratified suspensions.

11.
Endocrinology ; 162(10)2021 10 01.
Article in English | MEDLINE | ID: mdl-34270714

ABSTRACT

Energetic status often affects reproductive function, glucose homeostasis, and feeding in mammals. Malnutrition suppresses pulsatile release of the gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) and increases gluconeogenesis and feeding. The present study aims to examine whether ß-endorphin-µ-opioid receptor (MOR) signaling mediates the suppression of pulsatile GnRH/LH release and an increase in gluconeogenesis/feeding induced by malnutrition. Ovariectomized female rats treated with a negative feedback level of estradiol-17ß (OVX + low E2) receiving 2-deoxy-D-glucose (2DG), an inhibitor of glucose utilization, intravenously (iv) were used as a malnutrition model. An administration of D-Phe-Cys-Tyr-D-Trp-Orn-Thr-Pen-Thr-NH2 (CTOP), a selective MOR antagonist, into the third ventricle blocked the suppression of the LH pulse and increase in gluconeogenesis/feeding induced by iv 2DG administration. Histological analysis revealed that arcuate Kiss1 (kisspeptin gene)-expressing cells and preoptic Gnrh1 (GnRH gene)-expressing cells co-expressed little Oprm1 (MOR gene), while around 10% of arcuate Slc17a6 (glutamatergic marker gene)-expressing cells co-expressed Oprm1. Further, the CTOP treatment decreased the number of fos-positive cells in the paraventricular nucleus (PVN) in OVX + low E2 rats treated with iv 2DG but failed to affect the number of arcuate fos-expressing Slc17a6-positive cells. Taken together, these results suggest that the central ß-endorphin-MOR signaling mediates the suppression of pulsatile LH release and that the ß-endorphin may indirectly suppress the arcuate kisspeptin neurons, a master regulator for GnRH/LH pulses during malnutrition. Furthermore, the current study suggests that central ß-endorphin-MOR signaling is also involved in gluconeogenesis and an increase in food intake by directly or indirectly acting on the PVN neurons during malnutrition in female rats.


Subject(s)
Arcuate Nucleus of Hypothalamus/metabolism , Gonadotropin-Releasing Hormone/metabolism , Luteinizing Hormone/metabolism , Narcotic Antagonists/pharmacology , Paraventricular Hypothalamic Nucleus/metabolism , Receptors, Opioid, mu/metabolism , beta-Endorphin/metabolism , Animals , Blood Glucose/analysis , Female , Gluconeogenesis , Hypothalamus , Kisspeptins/metabolism , Rats , Rats, Wistar , Receptors, Opioid, mu/biosynthesis , Signal Transduction , Vesicular Glutamate Transport Protein 2/biosynthesis
12.
Case Rep Gastrointest Med ; 2021: 9939898, 2021.
Article in English | MEDLINE | ID: mdl-34327029

ABSTRACT

Primary hepatic squamous cell carcinoma (SCC) is a rare malignancy with aggressive clinical features. This is the first case report of a primary hepatic SCC diagnosed by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA), which is a reliable and safe procedure for the histopathological diagnosis of liver lesions, even if the percutaneous approach is difficult due to ascites or hypervascularity at the puncture site. A 52-year-old man presented to the emergency department of a tertiary referral hospital with right upper quadrant abdominal pain and abdominal distention. Given the laboratory data, a diagnosis of spontaneous bacterial peritonitis (SBP) was made. Concurrently, an abdominal computed tomography (CT) scan revealed an 8 cm hypodense mass with delayed peripheral enhancement in the left hepatic lobe and paraaortic and perihepatic lymphadenopathy. As persistent ascites precluded percutaneous liver biopsy, we performed EUS-FNA of the liver mass, and the obtained specimen showed SCC. As otorhinolaryngological consultation and whole-body investigations, including chest CT, upper and lower endoscopy, and positron emission tomography CT, were all unremarkable except for the liver lesion and lymph nodes, a diagnosis of primary hepatic SCC with systemic lymph node metastasis was made. After treatment of SBP with antibiotics, we initiated chemotherapy concurrent with radiation therapy, adapted to his liver function. Radiation and three cycles of chemotherapy were not effective as the disease progressed, as seen on the follow-up CT scan, and the patient died of hepatic failure on the 134th day after diagnosis. In conclusion, EUS-FNA was a reliable method for tissue sampling in liver malignancies, particularly in selected patients with contraindications for percutaneous biopsy.

13.
Phys Chem Chem Phys ; 23(16): 10070-10080, 2021 Apr 28.
Article in English | MEDLINE | ID: mdl-33871005

ABSTRACT

Polymeric materials are considered as promising electrolytes for all-solid-state secondary lithium batteries with superior energy and power densities, long cycle lives, and high safety. To further improve the ionic conductivity of polymer electrolytes, the development of a simple and efficient method that enables precise tuning of the three key factors, polymer segmental dynamics, Li+ coordination structure, and salt dissociability, is desired. In this study, we focus on an amidation reaction, which is a simple reaction with broad applicability, to explore the impact of the side-chain structure on the intermolecular interactions within the polymer, which dictates the aforementioned key factors. We synthesized a series of polyoxetane-based polymers having different branched side-chains, i.e., methyl (PtBuOA) and bulky cyanoethoxy (P3CEOA) groups, via amidation reaction. Spectro(electro)chemical analysis verified that the large steric hindrance of the cyanoethoxy side-chain effectively breaks the hydrogen bond network and dipole interaction within the polymer, both of which decrease the polymer segmental mobility, leading to better long-range Li+ conduction. Furthermore, the unique Li+ coordination structure consisting of a cyano group, ether/carboxyl oxygen, and TFSA anion in P3CEOA electrolytes has moderate stability, which effectively promotes the short-range Li+ conduction. The amide group, with a relatively high dielectric constant, improves the dissociability of lithium salt. We confirmed a more than three orders of magnitude improvement in ionic conductivity by introducing the cyanoethoxy side-chain, than that obtained by introducing the PtBuOA electrolyte with a methyl side-chain. This work provides a holistic picture of the effect of the side-chain structure on the intermolecular interaction and establishes the new design strategy for polymer electrolytes, which enables the precise tuning of the molecular interaction using the side-chain structure.

14.
RSC Adv ; 11(29): 18093-18102, 2021 May 13.
Article in English | MEDLINE | ID: mdl-35480203

ABSTRACT

Lithium-sulfur batteries hold promising potential for next-generation high-energy-density energy storage. One of their major technical problems is the sulfur active material loss and significant volume change during the charge-discharge process, resulting in rapid capacity fading. Here, we propose sulfur-inserted polymer-anchored edge exfoliated graphite as a positive electrode to accommodate the conflicting requirement of physically restraining sulfur dissolution while maintaining structural flexibility to cope with the volume expansion. The introduction of sulfur between the flexible polymer-anchored graphene layers is achieved by a simple chemical reaction at ambient temperature. The obtained sulfur-carbon composite demonstrates superior sulfur efficiency and cyclability compared to mesoporous carbon-based counterparts. The strong interfacial attraction between sulfur and highly-conductive graphene sheets at the confined interlayer space enables rapid charge transfer and effectively inhibits the polysulfide dissolution, resulting in improved redox reaction reversibility and sulfur efficiency. More importantly, the structural flexibility of layered structure, derived from polymer-anchor, guarantees the stable cycling by accommodating the significant volume expansion of sulfur active materials. Our work provides a simple, proof-of-concept strategy for improving the overall performance of carbon-based positive electrode for Li-S batteries.

15.
Endocrinology ; 161(11)2020 11 01.
Article in English | MEDLINE | ID: mdl-32894768

ABSTRACT

Malnutrition suppresses reproductive functions in mammals, which is considered to be mostly due to the inhibition of pulsatile gonadotropin-releasing hormone (GnRH)/gonadotropin secretion. Accumulating evidence suggests that kisspeptin neurons in the arcuate nucleus (ARC) play a critical role in the regulation of pulsatile GnRH/gonadotropin release. The present study aimed to examine if the hypothalamic dynorphin A (Dyn) neurons mediate the suppression of GnRH/luteinizing hormone (LH) pulses during malnutrition. Ovariectomized rats treated with a negative feedback level of estradiol-17ß-treated (OVX+E2) were administered with intravenous (iv) or fourth cerebroventricle (4V) 2-deoxy-D-glucose (2DG), an inhibitor of glucose utilization, to serve as a malnutrition model. Central administration of a Dyn receptor antagonist blocked the iv- or 4V-2DG-induced suppression of LH pulses in OVX+E2 rats. The 4V 2DG administration significantly increased the number of Pdyn (Dyn gene)-positive cells co-expressing fos in the paraventricular nucleus (PVN), but not in the ARC and supraoptic nucleus (SON), and the iv 2DG treatment significantly increased the number of fos and Pdyn-co-expressing cells in the PVN and SON, but decreased it in the ARC. The E2 treatment significantly increased Pdyn expression in the PVN, but not in the ARC and SON. Double in situ hybridization for Kiss1 (kisspeptin gene) and Oprk1 (Dyn receptor gene) revealed that around 60% of ARC Kiss1-expressing cells co-expressed Oprk1. These results suggest that the PVN Dyn neurons, at least in part, mediate LH pulse suppression induced by the hindbrain or peripheral glucoprivation, and Dyn neurons may directly suppress the ARC kisspeptin neurons in female rats.


Subject(s)
Dynorphins/metabolism , Food Deprivation/physiology , Luteinizing Hormone/metabolism , Neurons/physiology , Paraventricular Hypothalamic Nucleus , Rhombencephalon/metabolism , Animals , Down-Regulation/drug effects , Female , Glucose/metabolism , Glucose/pharmacology , Kisspeptins/metabolism , Malnutrition/metabolism , Neurons/metabolism , Paraventricular Hypothalamic Nucleus/cytology , Paraventricular Hypothalamic Nucleus/drug effects , Paraventricular Hypothalamic Nucleus/metabolism , Rats , Rats, Wistar , Rhombencephalon/drug effects
16.
J Pharm Pharm Sci ; 21(1): 195-206, 2018.
Article in English | MEDLINE | ID: mdl-29891024

ABSTRACT

PURPOSE: The chemotherapeutic agent irinotecan is hydrolyzed to its active form SN-38 by human carboxyesterases, but SN-38 is converted into the inactive form SN-38G by hepatic UDP-glucuronosyltransferases (UGTs). The aim of the present study was to evaluate the inhibitory effects of two b-glucuronidase-treated Japanese traditional herbal medicines (kampo), Hange-Shashin-To (TJ-14) and Sairei-To (TJ-114) on SN-38 glucuronidation, and the deglycosylation of baicalin (BG) and glycyrrhizic acid (GL) derived from TJ-14 and TJ-114 to form their respective aglycones, baicalein (BA) and glycyrrhetinic acid (GA). METHODS: The inhibitory effects of b-glucuronidase-treated TJ-14 and TJ-114 on SN-38 glucuronidation by human liver microsomes were examined. BA and GA, which were enzymatically converted from BG and GL present in TJ-14 and TJ-114, were examined in the same manner. Furthermore, the enzymatic activities were measured by using recombinant UGT1A1 and UGT1A9 isoforms instead of human liver microsomes. BA, GA, SN-38, and their glycosides/glucuronides were analyzed with an LC-MS system. RESULTS: As regards the linear initial reaction rate, SN-38 glucuronidation by human liver microsomes was significantly inhibited by the addition of b-glucuronidase-untreated TJ-14 and TJ-114, but was more strongly inhibited by the addition of b-glucuronidase-treated TJ-14 and TJ-114. The results of LC-MS analysis and pharmacokinetic studies suggested that BA is the main inhibitor of SN-38 glucuronidation. In the Dixon plot, BA showed competitive inhibition of SN-38 glucuronidation, and the inhibition constant was 8.70 ± 3.24 mM. Previous reports, studies of recombinant UGT isoforms indicated that SN-38 glucuronidation was mainly catalyzed by UGT1A1. CONCLUSIONS: These findings strongly suggested that SN-38 glucuronidation is inhibited by BA. BA could act as a pharmacokinetic regulating factor associated with SN-38 glucuronidation. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.


Subject(s)
Enzyme Inhibitors/pharmacology , Flavanones/pharmacology , Glucuronides/antagonists & inhibitors , Irinotecan/antagonists & inhibitors , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/isolation & purification , Flavanones/chemistry , Flavanones/isolation & purification , Glucuronidase/antagonists & inhibitors , Glucuronidase/metabolism , Glucuronides/metabolism , Glycyrrhizic Acid/chemistry , Glycyrrhizic Acid/isolation & purification , Glycyrrhizic Acid/pharmacology , Herbal Medicine , Humans , Irinotecan/metabolism , Japan , Kinetics , Microsomes, Liver/drug effects , Microsomes, Liver/metabolism , Time Factors
17.
ACS Omega ; 3(5): 4932-4940, 2018 May 31.
Article in English | MEDLINE | ID: mdl-31458709

ABSTRACT

Alminoprofen, (RS)-2-{4-[(2-methylprop-2-en-1-yl)amino]phenyl}propanoic acid (ALP) 1, is a racemic drug categorized as a 2-arylpropanoic acid-class nonsteroidal anti-inflammatory drug. Pharmacokinetic studies of 1 in patients have revealed that the corresponding acyl glucuronide 5 is a major urinary metabolite, but little is known about the structure and stereochemistry of 5. The present work describes the synthesis of a diastereomeric mixture of 1-ß-O-acyl glucuronides (2RS)-5 from 1 and methyl 2,3,4-tri-O-acetyl-1-bromo-1-deoxy-α-d-glucopyranuronate 2 using our chemo-enzymatic method that has complete specificity for the ß-configuration. The structure of (2RS)-5 was characterized by 1H and 13C NMR spectroscopy and high-resolution mass spectrometry as well as by complete hydrolysis by ß-glucuronidase. The absolute stereochemistry of (2RS)-5 was determined by comparison with (2R)-5 synthesized alternatively from (2R)-1 and 2. Compound (2R)-1 was prepared in two steps starting from chiral (R)-2-(4-nitrophenyl)propanoic acid (2R)-6. Chiral resolution of (2RS)-1 was achieved using a chiral high-performance liquid chromatography column, and its stereochemistry was determined by comparison with (2R)-1. The intrinsic degradation rate constant of (2R)-5 was 0.405 ± 0.002 h-1, which is approximately twice that of (2S)-5 (the k value was 0.226 ± 0.002 h-1) under physiological conditions (pH 7.40, 37 °C).

18.
Intern Med ; 55(23): 3445-3452, 2016.
Article in English | MEDLINE | ID: mdl-27904107

ABSTRACT

An epidermoid cyst arising within an intrapancreatic accessory spleen (ECIAS) is rare, and also difficult to correctly diagnose before surgery. It is mostly misdiagnosed as a cystic tumor, such as a mucinous cystic neoplasm or as a solid tumor with cystic degeneration, such as a neuro endocrine tumor. We herein report a case of ECIAS and also perform a literature review of 35 reports of ECIAS. Although the preoperative diagnosis of ECIAS using conventional imaging is relatively difficult to make, careful preoperative examinations of the features on computed tomography and magnetic resonance imaging could lead to a correct preoperative diagnosis of ECIAS which might thereby reduce the number of unnecessary resections.


Subject(s)
Epidermal Cyst/diagnosis , Splenic Diseases/diagnosis , Adult , Diagnosis, Differential , Epidermal Cyst/diagnostic imaging , Epidermal Cyst/surgery , Female , Humans , Magnetic Resonance Imaging , Pancreatic Neoplasms/diagnosis , Physical Examination , Spleen/pathology , Splenic Diseases/diagnostic imaging , Splenic Diseases/surgery , Tomography, X-Ray Computed
19.
Intern Med ; 55(18): 2617-21, 2016.
Article in English | MEDLINE | ID: mdl-27629956

ABSTRACT

An 87-year-old woman on oral prednisolone was diagnosed with a cholecystoduodenal fistula (CDF) caused by a cytomegalovirus-associated duodenal ulcer (DU) and was managed conservatively. A CDF caused by a DU is extremely rare. Although surgical repair is recommended for the treatment of a CDF caused by cholecystolithiasis, appropriate treatment for CDF caused by a DU remains controversial. This case report of a CDF caused by a DU suggests that conservative treatment is feasible in the absence of DU-associated complications, such as an untreatable hemorrhage or obstruction; this finding is compatible with previously reported cases that were conservatively treated.


Subject(s)
Biliary Fistula/therapy , Conservative Treatment , Cytomegalovirus Infections/complications , Duodenal Ulcer/therapy , Intestinal Fistula/therapy , Aged , Biliary Fistula/diagnostic imaging , Biliary Fistula/etiology , Cholelithiasis/diagnostic imaging , Cytomegalovirus , Cytomegalovirus Infections/therapy , Duodenal Ulcer/diagnostic imaging , Duodenal Ulcer/ethnology , Female , Humans , Intestinal Fistula/diagnostic imaging , Intestinal Fistula/etiology , Intestinal Obstruction/diagnostic imaging
20.
Clin J Gastroenterol ; 8(4): 240-6, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26210692

ABSTRACT

Repeated cytology of pancreatic juice obtained by endoscopic nasopancreatic drainage (ENPD) tube has been highlighted as an early diagnostic method for small pancreatic cancer, including carcinoma in situ. We report two cases of early-stage pancreatic cancer diagnosed using repeated cytology; both cases underwent curative resection. No significant masses were found on conventional imaging in either case, with only pancreatic duct strictures being observed. ENPD tubes were placed to collect pancreatic juice in both cases. In case 1, two of five pancreatic juice samples showed adenocarcinoma. Therefore, distal pancreatectomy was performed, and a PanIN3 grade neoplasm (carcinoma in situ) was identified at the branch duct near the distal stricture. In case 2, two of seven pancreatic juice samples (collected during the second tube placement) showed adenocarcinoma. Therefore, distal pancreatectomy was performed, and a PanIN3 neoplasm was identified primarily in the pancreatic duct at a narrow section with fibrosis. Partial microinvasion (<1 mm) was observed at the branch duct. Repeated cytology of pancreatic juice obtained by ENPD tube is effective for early diagnosis of pancreatic cancer, especially in cases without mass formation. However, some issues, including the appropriate number of samples, should be addressed in large prospective studies.


Subject(s)
Adenocarcinoma/diagnosis , Carcinoma in Situ/diagnosis , Cytodiagnosis/methods , Drainage/instrumentation , Early Detection of Cancer/methods , Pancreatic Juice/cytology , Pancreatic Neoplasms/diagnosis , Adenocarcinoma/surgery , Aged , Aged, 80 and over , Carcinoma in Situ/surgery , Female , Humans , Male , Pancreatectomy , Pancreatic Neoplasms/surgery
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