Sleep rebound leads to marked recovery of prolonged sleep deprivation-induced adversities in the stress response and hippocampal neuroplasticity of male rats.

BACKGROUND: Sleep disturbances are not only frequent symptoms, but also risk factors for major depressive disorder. We previously reported that depressed patients who experienced "Hypersomnia" showed a higher and more rapid response rate under paroxetine treatment, but the underlying mechanism remains unclear. The present study was conducted to clarify the beneficial effects of sleep rebound through an experimental "Hypersomnia" rat model on glucocorticoid and hippocampal neuroplasticity associated with antidepressive potency. METHODS: Thirty-four male Sprague-Dawley rats were subjected to sham treatment, 72-h sleep deprivation, or sleep deprivation and subsequent follow-up for one week. Approximately half of the animals were sacrificed to evaluate adrenal weight, plasma corticosterone level, hippocampal content of mRNA isoforms, and protein of the brain-derived neurotrophic factor (Bdnf) gene. In the other half of the rats, Ki-67- and doublecortin (DCX)-positive cells in the hippocampus were counted via immunostaining to quantify adult neurogenesis. RESULTS: Prolonged sleep deprivation led to adrenal hypertrophy and an increase in the plasma corticosterone level, which had returned to normal after one week follow-up. Of note, sleep deprivation-induced decreases in hippocampal Bdnf transcripts containing exons II, IV, VI, and IX and BDNF protein levels, Ki-67-(+)-proliferating cells, and DCX-(+)-newly-born neurons were not merely reversed, but overshot their normal levels with sleep rebound. LIMITATIONS: The present study did not record electroencephalogram or assess behavioral changes of the sleep-deprived rats. CONCLUSIONS: The present study demonstrated that prolonged sleep deprivation-induced adversities are reversed or recovered by sleep rebound, which supports "Hypersomnia" in depressed patients as having a beneficial pharmacological effect.

Factor Analysis of Fatigue in the Early Stages of Cancer Chemotherapy.

Patients undergoing chemotherapy for cancer frequently experience fatigue, which can significantly lower their quality of life and interfere with treatment. However, the risk factors for the occurrence of chemotherapy-induced fatigue (CIF) are unclear. In this study, we investigated the occurrence of CIF in 415 patients newly treated with chemotherapy at Fukuoka University Hospital between December 2020 and July 2022, and analyzed the factors that influence the occurrence of fatigue. The observation period was defined as the two-week period starting from the day after the induction of chemotherapy, and we collected data retrospectively from medical records. Fatigue was assessed based on Common Terminology Criteria for Adverse Events (CTCAE) version 5.0 by pharmacists who interviewed patients. The prevalence of fatigue was 56.4% (234/415). Nausea and vomiting, anorexia, hypoalbuminemia, and a high blood urea nitrogen/creatinine (BUN/Cr) ratio were extracted as risk factors for CIF. The prevalence of fatigue in 95 patients with nausea and vomiting was 83.2% (79/95), of whom 74.7% (59/79) had concomitant anorexia. Patients with nausea and vomiting had a high prevalence of both fatigue and anorexia, indicating that control for nausea and vomiting is crucial for the prevention of CIF. The serum albumin level reflects the nutritional status of patients approximately three weeks before chemotherapy, and BUN/Cr ≥20 indicates dehydration. Patients with a poor nutritional status or dehydration should be closely monitored for fatigue before and during treatment. These findings offer new prospects for healthcare providers to avoid or reduce CIF and improve patients' quality of life by early control of CIF risk factors.

Modified activity-based anorexia paradigm dampens chronic food restriction-induced hyperadiponectinemia in adolescent female mice.

Anorexia nervosa (AN) is a chronic, life-threatening disease with mental and physical components that include excessive weight loss, persistent food restriction, and altered body image. It is sometimes accompanied by hyperactivity, day-night reversal, and amenorrhea. No medications have been approved specific to the treatment of AN, partially due to its unclear etiopathogenesis. Because adiponectin is an appetite-regulating cytokine released by adipose tissue, we hypothesized that it could be useful as a specific biomarker that reflects the disease state of AN, so we developed a modified AN mouse model to test this hypothesis. Twenty-eight 3-week-old female C57BL/6J mice were randomly assigned to the following groups: 1) no intervention; 2) running wheel access; 3) food restriction (FR); and 4) activity-based anorexia (ABA) that included running wheel access plus FR. After a 10-day cage adaptation period, the mice of the FR and ABA groups were given 40% of their baseline food intake until 30% weight reduction (acute FR), then the body weight was maintained for 2.5 weeks (chronic FR). Running wheel activity and the incidence of the estrous cycle were assessed. Spontaneous food restriction and the plasma adiponectin level were evaluated at the end of the acute and chronic FR phases. An increase in running wheel activity was found in the light phase, and amenorrhea was found solely in the ABA group, which indicates that this is a good model of AN. This group showed a slight decrease in spontaneous food intake accompanied with an attenuated level of normally induced plasma adiponectin at the end of the chronic FR phase. These results indicate that the plasma adiponectin level may be a useful candidate biomarker for the status or stage of AN.

Dynamic Changes of Behavioral Despair, HPA Axis Activity, and Hippocampal Neurogenesis in Male Rats Induced by Social Defeat Stress.

BACKGROUND: Psychosocial stress factors, such as threat and defeat, are major risk factors for the development of depression. The precise mechanisms underlying stress-induced depression are not clearly understood because the stress response in the brain varies in a stress-frequency-dependent manner. In the current research milieu on the pathogenesis of depression, the focus is on depression-like behavioral phenotype, hypothalamic-pituitary-adrenal (HPA) axis, and hippocampal neurogenesis. However, most studies have evaluated the symptomatic features of depression at certain time points after exposure to psychosocial stress. Here, we examined the frequency-dependent effects of psychosocial stress on depression-related features in rats. METHODS: In the present study, different frequencies (one, two, three, or four times) of psychosocial stress were applied to 19 male Sprague-Dawley rats using a resident/intruder paradigm. Subsequently, the rats were subjected to a stress reactivity test to evaluate HPA axis activity, following which assessments of immobility behavior in the forced swimming test (FST) and adult neurogenesis were conducted. RESULTS: One-time stressed rats showed a decrease in immobility behavior in the FST and the amount of doublecortin (DCX)-positive cells. Two-time stress caused hypoactivity of the HPA axis. In contrast, immobility behavior and HPA axis activity were increased after four-time stress exposure, but the number of DCX-positive cells was decreased. CONCLUSIONS: Our findings suggest that psychosocial stress produces a biphasic effect on the symptoms of depression in a stress-frequency-dependent manner, which could provide insights to facilitate further pathogenesis research on depression.

Upregulations of α1 adrenergic receptors and noradrenaline synthases in the medial prefrontal cortex are associated with emotional and cognitive dysregulation induced by post-weaning social isolation in male rats.

Early-life social isolation induces emotional and cognitive dysregulation, such as increased aggression and anxiety, and decreases neuron excitability in the medial prefrontal cortex (mPFC). The noradrenergic system in the mPFC regulates emotion and cognitive function via α1 or α2A adrenergic receptors, depending on noradrenaline levels. However, social isolation-induced changes in the mPFC noradrenergic system have not been reported. Here, male Wistar rats received post-weaning social isolation for nine consecutive weeks and were administered behavioral tests (novel object recognition, elevated plus maze, aggression, and forced swimming, sequentially). Protein expression levels in the mPFC noradrenergic system (α1 and α2A adrenergic receptors, tyrosine hydroxylase, and dopamine-ß-hydroxylase used as indices of noradrenaline synthesis and release) were examined through western blotting. Social isolation caused cognitive dysfunction, anxiety-like behavior, and aggression, but not behavioral despair. Socially-isolated rats exhibited increased protein levels of the α1 adrenergic receptor, tyrosine hydroxylase, and dopamine-ß-hydroxylase in the mPFC; there was no significant difference between the groups in the α2A adrenergic receptor expression levels. Preferential activation of the α1 adrenergic receptor caused by high noradrenaline concentration in the mPFC may be involved in social isolation-induced emotional and cognitive regulation impairments. Targeting the α1 adrenergic receptor signaling pathway is a potential therapeutic strategy for psychiatric disorders with symptomatic features such as emotional and cognitive dysregulation.

Recovery Sleep Immediately after Prolonged Sleep Deprivation Stimulates the Transcription of Integrated Stress Response-Related Genes in the Liver of Male Rats.

Sleep loss induces performance impairment and fatigue. The reactivation of human herpesvirus-6, which is related to the phosphorylation of eukaryotic translation initiation factor 2α (eIF2α), is one candidate for use as an objective biomarker of fatigue. Phosphorylated eIF2α is a key regulator in integrated stress response (ISR), an intracellular stress response system. However, the relation between sleep/sleep loss and ISR is unclear. The purpose of the current study was to evaluate the effect of prolonged sleep deprivation and recovery sleep on ISR-related gene expression in rat liver. Eight-week-old male Sprague-Dawley rats were subjected to a 96-hour sleep deprivation using a flowerpot technique. The rats were sacrificed, and the liver was collected immediately or 6 or 72 h after the end of the sleep deprivation. RT-qPCR was used to analyze the expression levels of ISR-related gene transcripts in the rat liver. The transcript levels of the Atf3, Ddit3, Hmox-1, and Ppp15a1r genes were markedly increased early in the recovery sleep period after the termination of sleep deprivation. These results indicate that both activation and inactivation of ISRs in the rat liver occur simultaneously in the early phase of recovery sleep.

Oxytocin treatment improves dexamethasone-induced depression-like symptoms associated with enhancement of hippocampal CREB-BDNF signaling in female mice.

AIMS: Chronic stress and glucocorticoid exposure are risk factors for depression. Oxytocin (OT) has been shown to have antistress and antidepressant-like effects in male rodents. However, depression is twice as common in women than in men, and it remains unclear whether OT exerts antidepressant-like effects in women with depression. Therefore, in this study, we investigated the therapeutic effect of chronic OT administration in a female mouse model of dexamethasone (DEX)-induced depression. METHODS: Female C57BL/6J mice were administered saline (vehicle, s.c.), DEX (s.c.), or OT (i.p.) + DEX (s.c.) daily for 8 weeks, and then assessed for anxiety- and depression-like behaviors. We also examined the hippocampal levels of phosphorylated cAMP response element-binding protein (p-CREB) and brain-derived neurotrophic factor (BDNF), which are important mediators of the response to antidepressants. RESULTS: Simultaneous OT treatment blocked the adverse effects of DEX on emotional behaviors. Furthermore, it upregulated p-CREB and BDNF in the hippocampus. CONCLUSION: OT may exert antidepressant-like effects by activating hippocampal CREB-BDNF signaling in a female mouse model of depression.

Inhibition of NR5A1 Phosphorylation Alleviates a Transcriptional Suppression Defect Caused by a Novel NR0B1 Mutation.

Context: Mutations in the NR0B1 gene, also well-known as the DAX1 gene, are known to cause congenital adrenal hypoplasia associated with hypogonadotropic hypogonadism. The abnormal NR0B1 protein fails to suppress the transcription of promoters of steroidogenic enzymes, which are also targets of NR5A1 protein, also well-known as Ad4BP/SF-1 protein. Since NR5A1 and NR0B1 have antagonistic effects on steroidogenesis, the loss of function due to NR0B1 mutations may be compensated by inducing loss of function of NR5A1 protein. Patient: A middle-aged man was diagnosed with congenital adrenal hypoplasia associated with hypogonadotropic hypogonadism and genetic analysis revealed him to have a novel NR0B1 mutation, c.1222C>T(p.Gln408Ter). Methods: NR0B1 activity was evaluated in CLK1/4 inhibitor-treated 293T cells via immunoblotting and luciferase assays of the STAR promoter. Results: TG003 treatment suppressed NR5A1 protein function to compensate for the mutant NR0B1 showing inhibited suppression of transcription. Immunoblotting analyses showed that the phosphorylation status of NR5A1 at Ser203 was attenuated by the CLK1/4 inhibitor. Conclusion: The specific reduction of NR5A1 phosphorylation by a CLK1/4 inhibitor may alleviate developmental defects in patients with NR0B1 mutations.

Behavioral profile in a Dctn1G71A knock-in mouse model of Perry disease.

Perry disease (Perry syndrome) is a rare, rapidly progressive, autosomal dominant neurodegenerative disease characterized by parkinsonism, depression/apathy, weight loss, and respiratory symptoms including central hypoventilation. It is caused by missense mutations (e.g. p.G71A) in the DCTN1 gene. We previously generated transgenic mice that expressed human DCTN1G71A mutant protein under the control of Thy1 promoter. These mice exhibited apathy-like behavior and parkinsonism. However, it is possible that this phenotype was due to a gene-dosage imbalance or transgene insertion position. To circumvent these potential caveats, we have generated a knock-in mouse model carrying a p.G71A mutation in Dctn1. Heterozygous Dctn1G71A and wild-type littermates were subjected to a battery of behavioral analyses. Furthermore, immunohistochemistry for tyrosine hydroxylase (TH) was performed on brain sections of these mice, and TH signal intensity in substantia nigral neurons was quantified. Dctn1G71A mice were immobile for longer than wild-type mice of the same age and sex in the tail-suspension test, revealing depressive characteristics. In addition, the beam-walking test and pole test detected motor deficits in Dctn1G71A female mice. Finally, immunostaining revealed a decrease in TH immunoreactivity in neurons of the substantia nigra in the Dctn1G71A mice. Collectively, heterozygous Dctn1G71A mice showed depression-like behavior, motor deficits, and a functional reduction in substantia nigral neurons, as judged by TH immunostaining, thereby exhibiting multiple features of Perry disease. Hence, this mouse model will be useful in elucidating pathological mechanisms of Perry disease and for developing novel therapeutic strategies against it.

Necessity of salt intake reduction education beginning in youth: a cross-sectional survey of sodium-to-potassium ratios in mothers and their preschool children.

Urinary sodium-to-potassium ratios are known to be high in preschoolers, but there are no reports comparing these ratios with those of the children's mothers. The aim of this study was to investigate the association between the urinary sodium-to-potassium ratios of mothers and their preschool children under the hypothesis that the ratio is equivalent between the two. We evaluated 297 preschoolers aged four to five attending six kindergartens (four in northern Japan, two in southern Japan), and we also evaluated the children's mothers. We asked the participants to take morning first urine samples for 2 consecutive days in the spring and autumn of the same year (four samples per participant) and to fill out a dietary questionnaire. There was a correlation between the urinary sodium-to-potassium ratios of preschoolers and those of their mothers. However, in a comparison between the preschoolers and their mothers overall, higher values were found in the preschoolers [preschoolers: 4.6 (3.5-6.3) mmol/L/g·Cr; mothers: 4.3 (3.9-4.7) mmol/L/g·Cr, p = 0.003]. These results correlated with the urinary sodium-to-potassium ratios estimated from the dietary questionnaire. The preschoolers showed high sodium and low potassium intake consumption compared to the mothers. Interestingly, these were found to differ by region and gender. In conclusion, the urinary sodium-to-potassium ratio in Japanese preschoolers is related to and higher than that of their mothers. It is important to educate children, their parents, childcare professionals, and society as a whole about proper salt restriction and potassium supplementation, as well as to improve the food environment.

Continuous psychosocial stress stimulates BMP signaling in dorsal hippocampus concomitant with anxiety-like behavior associated with differential modulation of cell proliferation and neurogenesis.

Bone morphogenetic protein (BMP) signaling in the hippocampus regulates psychiatric behaviors and hippocampal neurogenesis in non-stress conditions; however, stress-induced changes in hippocampal BMP signaling have not yet been reported. Therefore, we sought to examine whether psychosocial stress, which induces psychiatric symptoms, affects hippocampal BMP signaling. A total of 32 male Sprague-Dawley rats were exposed to a psychosocial stress using a Resident/Intruder paradigm for ten consecutive days. Subsequently, rats were subjected to a battery of behavioral tests (novelty-suppressed feeding test, sucrose preference test, and forced swimming test) for the evaluation of adult neurogenesis and activity of BMP signaling in the dorsal and ventral hippocampus. Repeated social defeat promoted anxiety-like behaviors, but neither anhedonia nor behavioral despair. Socially defeated rats exhibited an increase in the number of Ki-67-positive cells, decrease in the number of doublecortin (DCX)-positive cells, and decrease only in the dorsal hippocampus of the ratio of DCX-positive to Ki-67-positive cells, a proxy for newly-born cell maturation speed and survival. In contrast, no differences were observed in the number of 5-Bromo-2'-deoxyuridine (BrdU)-positive cells, indicating survival of newly-born cells both in the dorsal and ventral hippocampus. Furthermore, psychosocial stress significantly increased the BMP-4 and phosphorylated Smad1/5/9 expression levels specifically in the dorsal hippocampus. Our findings suggest that repeated psychosocial stress activates BMP signaling and differently affects cell proliferation and neurogenesis exclusively in the dorsal hippocampus, potentially exacerbating anxiety-related symptoms. Targeting BMP signaling is a potential therapeutic strategy for psychiatric disorders.

A self-monitoring urinary salt excretion level measurement device for educating young women about salt reduction: A parallel randomized trial involving two groups.

To prevent and treat hypertension, it is important to restrict salt in one's diet since adolescence. However, an effective salt-reduction education system has yet to be established. Besides accurate evaluation, we believe that the frequent usage of a measurement device may motivate individuals to avoid high salt intake. The present study evaluated the use of a urinary salt excretion measurement device for salt-reduction education in a parallel randomized trial of two groups. The sample comprised 100 university students who provided consent to participate. A survey with 24-hour home urine collection and blood pressure measurement was conducted. Participants in the self-monitoring group measured their own urinary salt excretion level for 4 weeks, using the self-measurement device. Analyses were conducted on 51 participants in the control group and 49 in the self-monitoring group. At baseline, there was no significant difference between the two groups in terms of their characteristics and 24-hour urinary salt excretion levels. After intervention, 24-hour urinary sodium/potassium ratio showed no change in the control group [baseline score: 4.1 ± 1.5; endline score: 4.2 ± 2.0; P = 0.723], but it decreased significantly in the self-monitoring group [baseline score: 4.0 ± 1.7; endline score: 3.5 ± 1.4; P = 0.044]. This change was significant even after adjusting for baseline and endline differences between groups using analysis of covariance (P = 0.045). The self-monitoring urinary salt excretion measurement device improved the 24-hour urinary sodium/potassium ratio. The device is a useful and practical tool for educating young individuals about dietary salt reduction.

Circular IRE-type RNAs of the NR5A1 gene are formed in adrenocortical cells.

The recently discovered circular RNAs (circRNAs) are mostly formed by back-splicing where the downstream 5' splice site splices to the upstream 3' splice site by conventional pre-mRNA splicing. These circRNAs regulate gene expression by acting as sponges for micro-RNAs or RNA-binding proteins. Here we show that the NR5A1 (previously called Ad4BP or SF-1) gene which is exclusively expressed in the adrenal cortex and steroidogenic tissue can form atypical circRNAs by unconventional splicing. Two stem loops with inositol-requiring protein-1α (IRE1α) cleavage sites are connected by an IRE1α cleavage site to form a circRNA (circIRE RNA). From total RNA of normal human adrenal cortex, we detected a circIRE RNA with connected ends by IRE1α cleavage sites in exon 6 and exon 1 (circIRE NR5A1 ex6-1 RNA). circIRE NR5A1 ex6-1 RNA was not detected in the adrenocortical cancer cell line, H295R. When IRE1α was expressed in H295R cells a different circIRE NR5A1 RNA connecting IRE1-cleavage sites in exon 7 and exon 1 was detected (circIRE NR5A1 ex7-1 RNA). The expression of this circIRE RNA was inhibited by the IRE1 inhibitor 1, STF-083010, implicating that it was formed via the ER stress pathway, where IRE1α is a major factor. This is the first report of this type of circular RNA connected by IRE1-cleavage sites found to be expressed in mammalian cells in a tissue-specific manner. To our surprise, the concomitant expression of NR5A1 was increased by IRE1α implicating that NR5A1 was not subjected to IRE1-dependent decay of mRNA (RIDD) but rather activating a transcriptional regulatory network to cope with ER stress in steroidogenic tissue reminiscent to XBP1 in other tissue. We believe this is the first report of such tissue-specific transcriptional cascade responding to ER stress as well as the novel finding of circular RNAs connected by IRE1α cleavage sites expressed in mammalian tissue.

Chronic administration of quetiapine stimulates dorsal hippocampal proliferation and immature neurons of male rats, but does not reverse psychosocial stress-induced hyponeophagic behavior.

Quetiapine, an atypical antipsychotic, has been used for the treatment of several neuropsychiatric disorders. However, the underlying mechanism of the broad therapeutic range of quetiapine remains unknown. We previously reported that several aversive conditions affect dorsal/ventral hippocampal neurogenesis differentially. This study was aimed to elucidate the positive effects of chronic treatment with quetiapine on regional differences in hippocampal proliferation and immature neurons and behavioral changes under psychosocial stress using the Resident-Intruder paradigm. Twenty-three male Sprague-Dawley rats were intraperitoneally administered a vehicle or quetiapine (10 mg/kg) once daily for 28 days. Two weeks after starting the injections, animals were exposed to intermittent social defeat (four times over two weeks). The behavioral effects of stress and quetiapine were evaluated by the Novelty-Suppressed Feeding (NSF) test. The stereological quantification of hippocampal neurogenesis was estimated using immunostaining with Ki-67 and doublecortin (DCX). Chronic quetiapine treatment stimulated the Ki-67- and DCX-positive cells in the dorsal hippocampus, but not in the ventral subregion. The stress-induced changes in neurogenesis and hyponeophagic behavior were not reversed by repeated administration of quetiapine. Future study with additional behavioral tests is needed to elucidate the functional significance of the quetiapine-induced increase in dorsal hippocampal neurogenesis.

Antitumor Effects and Delivery Profiles of Menahydroquinone-4 Prodrugs with Ionic or Nonionic Promoiety to Hepatocellular Carcinoma Cells.

Hepatocellular carcinoma (HCC) shows poor prognosis owing to its very frequent recurrence even after curative treatment. Thus, an effective and safe long-term chemopreventive agent is strongly in demand. Menahydroquinone-4 (MKH) is an active form of menaquinone-4 (MK-4, vitamin K2) that is involved in the synthesis of vitamin K-dependent proteins in the liver. We hypothesized that efficient delivery of MKH might be critical to regulate HCC proliferation. The discovery of a suitable prodrug targeting HCC in terms of delivery and activation could reduce the clinical dose of MK-4 and maximize efficacy and safety. We previously showed that MKH dimethylglycinate (MKH-DMG) enables effective delivery of MKH into HCC cells and exhibits strong antitumor effects compared with MK-4. In this study, we prepared anionic MKH hemi-succinate (MKH-SUC) and non-ionic MKH acetate (MKH-ACT), in addition to cationic MKH-DMG, and evaluated MKH delivery profiles and antitumor effects in vitro. MKH-SUC showed the highest uptake and the most efficient release of MKH among the examined compounds and exhibited rapid and strong antitumor effects. These results indicate that MKH-SUC might have a good potential as an MKH delivery system for HCC that overcomes the limitations of MK-4 as a clinical chemopreventive agent.

HMGA1a Induces Alternative Splicing of the Estrogen Receptor-αlpha Gene by Trapping U1 snRNP to an Upstream Pseudo-5' Splice Site.

Objectives: The high-mobility group A protein 1a (HMGA1a) protein is known as a transcription factor that binds to DNA, but recent studies have shown it exerts novel functions through RNA-binding. We were prompted to decipher the mechanism of HMGA1a-induced alternative splicing of the estrogen receptor alpha (ERα) that we recently reported would alter tamoxifen sensitivity in MCF-7 TAMR1 cells. Methods: Endogenous expression of full length ERα66 and its isoform ERα46 were evaluated in MCF-7 breast cancer cells by transient expression of HMGA1a and an RNA decoy (2'-O-methylated RNA of the HMGA1a RNA-binding site) that binds to HMGA1a. RNA-binding of HMGA1a was checked by RNA-EMSA. In vitro splicing assay was performed to check the direct involvement of HMGA1a in splicing regulation. RNA-EMSA assay in the presence of purified U1 snRNP was performed with psoralen UV crosslinking to check complex formation of HMGA1a-U1 snRNP at the upstream pseudo-5' splice site of exon 1. Results: HMGA1a induced exon skipping of a shortened exon 1 of ERα in in vitro splicing assays that was blocked by the HMGA1a RNA decoy and sequence-specific RNA-binding was confirmed by RNA-EMSA. RNA-EMSA combined with psoralen UV crosslinking showed that HMGA1a trapped purified U1 snRNP at the upstream pseudo-5' splice site. Conclusions: Regulation of ERα alternative splicing by an HMGA1a-trapped U1 snRNP complex at the upstream 5' splice site of exon 1 offers novel insight on 5' splice site regulation by U1 snRNP as well as a promising target in breast cancer therapy where alternative splicing of ERα is involved.

HMGA1a induces alternative splicing of estrogen receptor alpha in MCF-7 human breast cancer cells.

The high-mobility group A protein 1a (HMGA1a) protein is known as an oncogene whose expression level in cancer tissue correlates with the malignant potential, and known as a component of senescence-related structures connecting it to tumor suppressor networks in fibroblasts. HMGA1 protein binds to DNA, but recent studies have shown it exerts novel functions through RNA-binding. Our previous studies have shown that sequence-specific RNA-binding of HMGA1a induces exon-skipping of Presenilin-2 exon 5 in sporadic Alzheimer disease. Here we show that HMGA1a induced exon-skipping of the estrogen receptor alpha (ERα) gene and increased ERα46 mRNA expression in MCF-7 breast cancer cells. An RNA-decoy of HMGA1a efficiently blocked this event and reduced ERα46 protein expression. Blockage of HMGA1a RNA-binding property consequently induced cell growth through reduced ERα46 expression in MCF-7 cells and increased sensitivity to tamoxifen in the tamoxifen-resistant cell line, MCF-7/TAMR1. Stable expression of an HMGA1a RNA-decoy in MCF-7 cells exhibited decreased ERα46 protein expression and increased estrogen-dependent tumor growth when these cells were implanted in nude mice. These results show HMGA1a is involved in alternative splicing of the ERα gene and related to estrogen-related growth as well as tamoxifen sensitivity in MCF-7 breast cancer cells.

Leptin attenuates D2 receptor-mediated inhibition of putative ventral tegmental area dopaminergic neurons.

Obesity causes hyperleptinemia. We have previously shown that D2 receptor-mediated inhibition of ventral tegmental area (VTA) dopaminergic neurons is attenuated in diet-induced mice with obesity. Consequently, we hypothesized that high concentrations of serum leptin during obesity might modulate D2 receptor-mediated effects on VTA dopaminergic neurons. To investigate our hypothesis, we examined leptin effects on D2 receptor-mediated inhibition of putative VTA dopaminergic neurons from lean mice using electrophysiological techniques. Leptin (100 nmol/L) directly inhibited spontaneous firing in 71% of putative VTA dopaminergic neurons (leptin-responsive), whereas the remaining 29% of neurons were leptin-nonresponsive. In 41% of leptin-responsive neurons, leptin attenuated the reduced firing rate produced by quinpirole (100 nmol/L), whereas the remaining 59% of neurons exhibited no effect of leptin. In leptin-nonresponsive neurons, no significant leptin-induced effect was observed on reduced firing rate produced by quinpirole. In leptin-responsive neurons with positive leptin-induced attenuation of quinpirole effects, leptin-induced attenuation persisted for >20 min, whereas no such persistent attenuation was observed in other types of neurons. In conclusion, leptin attenuates D2 receptor-mediated inhibition in a subpopulation of putative VTA dopaminergic neurons. We suggest that leptin directly decreases, and indirectly increases, excitability of VTA dopaminergic neurons. In turn, this may contribute to a change in feeding behavior through the mesolimbic dopaminergic system during the development of obesity.

Relevance of the Mini Nutritional Assessment in cirrhotic liver disease patients.

BACKGROUND AND OBJECTIVES: Malnutrition is an important prognostic factor for patients with liver disease and a novel nutritional assessment tool is required for these patients. The aim of this study was to validate the Mini Nutritional Assessment (MNA) as a nutritional screening tool for patients with liver disease, by comparing MNA scores with other nutrition-related parameters. METHODS AND STUDY DESIGN: Patients who were hospitalized at the gastroenterology division of Kyushu and Beppu Medical Center were enrolled. The study included 77 patients with liver disease (male/female, 46/31; mean±SD age, 68.5±10.7 years; liver cirrhosis, 64.9%; liver cancer, 61.0%). Correlations of MNA score at hospital admission with anthropometric parameters and blood test data were evaluated. RESULTS: In patients with liver disease, MNA scores demonstrated that 18 (23.4%) had normal nutritional status, 41 (53.2%) were at risk of malnutrition, and 18 (23.4%) were malnourished, indicating that up to 76.6% of the liver disease group were malnourished. Especially, patients with liver cirrhosis had lower scores of nutritional markers and MNA. The MNA score in liver cirrhotic patients correlated with the following parameters: % arm circumference, % triceps skinfolds, ratio of % maximum grasp strength and arm circumference, maximum grasp strength, arm muscle circumference, calf circumference, serum albumin levels, the controlling nutritional status score, and Onodera's prognostic index, while patients without liver cirrhosis did not show such correlation. CONCLUSIONS: MNA scores correlated with nutrition-related data in patients with liver cirrhosis. The MNA is an appropriate tool for nutritional screening assessment in these cirrhotic patients of any etiology.

Self-monitoring of urinary salt excretion as a method of salt-reduction education: a parallel, randomized trial involving two groups.

OBJECTIVE: The present study aimed to evaluate salt-reduction education using a self-monitoring urinary salt-excretion device. DESIGN: Parallel, randomized trial involving two groups. The following parameters were checked at baseline and endline of the intervention: salt check sheet, eating behaviour questionnaire, 24 h home urine collection, blood pressure before and after urine collection. SETTING: The intervention group self-monitored urine salt excretion using a self-measuring device for 4 weeks. In the control group, urine salt excretion was measured, but the individuals were not informed of the result. SUBJECTS: Seventy-eight individuals (control group, n 36; intervention group, n 42) collected two 24 h urine samples from a target population of 123 local resident volunteers. The samples were then analysed. RESULTS: There were no differences in clinical background or related parameters between the two groups. The 24 h urinary Na:K ratio showed a significant decrease in the intervention group (-1·1) compared with the control group (-0·0; P=0·033). Blood pressure did not change in either group. The results of the salt check sheet did not change in the control group but were significantly lower in the intervention group. The score of the eating behaviour questionnaire did not change in the control group, but the intervention group showed a significant increase in eating behaviour stage. CONCLUSIONS: Self-monitoring of urinary salt excretion helps to improve 24 h urinary Na:K, salt check sheet scores and stage of eating behaviour. Thus, usage of self-monitoring tools has an educational potential in salt intake reduction.