Efficacy and Safety of 5-Aminolevulinic Acid Combined with Iron on Skeletal Muscle Mass Index and Physical Performance of Patients with Sarcopenia: A Multicenter, Double-Blinded, Randomized-Controlled Trial (ALADDIN Study).

Sarcopenia is a geriatric syndrome characterized by decreased physical performance, muscle mass, and strength. Since the intake of 5-aminolevulinic acid (ALA) with iron can increase muscle mass and mitochondria in mice and elevate physical exercise performance in humans, the beneficial effects of ALA in patients with sarcopenia are expected, but this remains unexplored in the literature. This study aimed to assess the efficacy and dose dependency of ALA combined with iron in sarcopenia by measuring skeletal muscle mass index (SMI). Subjects with sarcopenia were enrolled and randomized into the ALA and sodium ferrous citrate (SFC) intake groups (ALA50/SFC29, ALA100/SFC29, ALA150/SFC29, ALA 100/SFC57, and ALA0/SFC29 placebo) and ingested the assigned study food for 12 weeks. The primary endpoint, the change in SMI from baseline to week 12, did not differ significantly between the groups. Hand grip significantly increased or tended to increase from baseline after 12 weeks with all doses of ALA or SFC compared with the placebo group. No consistent changes were observed in the other endpoints, including calf circumference, physical function, or quality of life (QOL). Although this study suggests safe administration and the possibility of ALA improving hand grip strength in patients with sarcopenia, further investigation is required.

HLA typing of patients who developed subacute thyroiditis and Graves' disease after SARS-CoV-2 vaccination: a case report.

BACKGROUND: Cases of subacute thyroiditis (SAT) after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination have been reported. A human leukocyte antigen (HLA) allele, HLA-B*35, appears to be involved in the pathogenesis of SAT. CASE PRESENTATION: We conducted HLA typing of one patient with SAT and another with both SAT and Graves' disease (GD), which developed after SARS-CoV-2 vaccination. Patient 1, a 58-year-old Japanese man, was inoculated with a SARS-CoV-2 vaccine (BNT162b2; Pfizer, New York, NY, USA). He developed fever (38 °C), cervical pain, palpitations, and fatigue on day 10 after vaccination. Blood chemistry tests revealed thyrotoxicosis and elevated serum C-reactive protein (CRP) and slightly increased serum antithyroid-stimulating antibody (TSAb) levels. Thyroid ultrasonography revealed the characteristic findings of SAT. Patient 2, a 36-year-old Japanese woman, was inoculated twice with a SARS-CoV-2 vaccine (mRNA-1273; Moderna, Cambridge, MA, USA). She developed fever (37.8 °C) and thyroid gland pain on day 3 after the second vaccination. Blood chemistry tests revealed thyrotoxicosis and elevated serum CRP, TSAb, and antithyroid-stimulating hormone receptor antibody levels. Fever and thyroid gland pain persisted. Thyroid ultrasonography revealed the characteristic findings of SAT (i.e., slight swelling and a focal hypoechoic area with decreased blood flow). Prednisolone treatment was effective for SAT. However, thyrotoxicosis causing palpitations relapsed thereafter, for which thyroid scintigraphy with 99mtechnetium pertechnetate was conducted, and the patient was diagnosed with GD. Thiamazole treatment was then initiated, which led to improvement in symptoms. CONCLUSION: HLA typing revealed that both patients had the HLA-B*35:01, -C*04:01, and -DPB1*05:01 alleles. Only patient 2 had the HLA-DRB1*11:01 and HLA-DQB1*03:01 alleles. The HLA-B*35:01 and HLA-C*04:01 alleles appeared to be involved in the pathogenesis of SAT after SARS-CoV-2 vaccination, and the HLA-DRB1*11:01 and HLA-DQB1*03:01 alleles were speculated to be involved in the postvaccination pathogenesis of GD.

Medical Record Survey after Comprehensive Health Checkup Referral and Its Contribution to the Early Detection of Cancer.

Comprehensive health checkups in Japan are a preventive method to detect cancer and metabolic diseases. Unlike group medical examinations, individual examinations in health checkups are possible, with additional tests possible for disease detection. However, it is difficult to accurately ascertain the results from only the report after referral to a medical institution in individuals suspected of having cancer who need to be examined. We aimed to conduct a medical record survey of patients referred to the Hospital after undergoing a comprehensive health checkup and investigate the contribution of comprehensive health checkups to the detection of cancer more accurately. The subjects were 1763 examinees who were referred to various departments of our hospital because of doubtful cancer from 23,128 examinees who underwent comprehensive health checkups in our center from January 2018 to December 2022 for 5 years. The medical record survey demonstrated that cancer was detected in more than twice as many individuals as reported and other sources. Early-stage cancers require a significantly longer time to establish a definitive diagnosis. In conclusion, short-term reports from the referring hospital are insufficient for a final diagnosis, and long-term follow-up is extremely important to increase the diagnosis rates of cancer for comprehensive health checkups.

Premature Acute Myocardial Infarction in a Young Patient With Sitosterolemia.

Sitosterolemia is a rare, inherited, autosomal recessive disorder of lipid metabolism characterized by increased levels of plant sterols, such as sitosterol and campesterol, xanthomas, and accelerated atherosclerosis. In a 15-year-old boy exhibiting ST-elevation acute myocardial infarction, lipid panels, including plant sterol, and genetic testing for the ATP-binding cassette sub-family G member 5 (ABCG5) gene mutation, confirmed the diagnosis of sitosterolemia. A comprehensive lipid panel and genetic testing should be considered in patients with premature coronary artery disease to prevent disease progression through dietary and pharmacologic interventions specific to sitosterolemia.

La sitostérolémie est une maladie génétique rare à transmission autosomique récessive touchant le métabolisme des lipides, qui est caractérisée par une augmentation des taux de stérols végétaux comme le sitostérol et le campestérol, la présence de xanthomes et une athérosclérose accélérée. Chez un garçon âgé de 15 ans ayant subi un infarctus aigu du myocarde avec élévation du segment ST, le diagnostic de sitostérolémie a été confirmé par un bilan lipidique comprenant un dosage des stérols d'origine végétale et un test génétique de dépistage de la mutation du gène ABCG5 (ATP-binding cassette sub-family G member 5). Un bilan lipidique exhaustif et un test génétique doivent être envisagés chez les patients présentant une coronaropathie prématurée afin de prévenir la progression de la maladie grâce à des interventions d'ordre tant diététique que pharmacologique propres à la sitostérolémie.

Neurofibromatosis Type 1 with Concurrent Multiple Endocrine Disorders: Adenomatous Goiter, Primary Hyperparathyroidism, and Acromegaly.

We encountered a 70-year-old Japanese woman with neurofibromatosis type 1 (NF1) who had a history of pheochromocytoma and concurrently developed adenomatous goiter, primary hyperparathyroidism, and acromegaly. The patient had a somatotroph adenoma of the adenohypophysis that predisposed her to multinodular goiter. Three parathyroid tumors were detected by cervical ultrasonography and cervicothoracic computed tomography. Genetic analyses did not reveal genetic alterations (e.g. loss-of-function mutation) in the causative genes of endocrine tumors, including MEN1, RET, VHL, CDKN1B, and CDKN2C. The NF1 gene could not be analyzed genetically due to the patient's refusal. The pathophysiologic mechanisms of endocrinopathy concurrence in NF1 remain to be elucidated.

Effects of Pparγ1 deletion on late-stage murine embryogenesis and cells that undergo endocycle.

Peroxisome proliferator-activated receptor (PPAR) γ1, a nuclear receptor, is abundant in the murine placenta during the late stage of pregnancy (E15-E16), although its functional roles remain unclear. PPARγ1 is encoded by two splicing isoforms, namely Pparγ1canonical and Pparγ1sv, and its embryonic loss leads to early (E10) embryonic lethality. Thus, we generated knockout (KO) mice that carried only one of the isoforms to obtain a milder phenotype. Pparγ1sv-KO mice were viable and fertile, whereas Pparγ1canonical-KO mice failed to recover around the weaning age. Pparγ1canonical-KO embryos developed normally up to 15.5 dpc, followed by growth delays after that. The junctional zone of Pparγ1canonical-KO placentas severely infiltrated the labyrinth, and maternal blood sinuses were dilated. In the wild-type, PPARγ1 was highly expressed in sinusoidal trophoblast giant cells (S-TGCs), peaking at 15.5 dpc. Pparγ1canonical-KO abolished PPARγ1 expression in S-TGCs. Notably, the S-TGCs had unusually enlarged nuclei and often occupied maternal vascular spaces, disturbing the organization of the fine labyrinth structure. Gene expression analyses of Pparγ1canonical-KO placentas indicated enhanced S-phase cell cycle signatures. EdU-positive S-TGCs in Pparγ1canonical-KO placentas were greater in number than those in wild-type placentas, suggesting that the cells continued to endoreplicate in the mutant placentas. These results indicate that PPARγ1, a known cell cycle arrest mediator, is involved in the transition of TGCs undergoing endocycling to the terminal differentiation stage in the placentas. Therefore, PPARγ1 deficiency, induced through genetic manipulation, leads to placental insufficiency.

Ezetimibe impairs transcellular lipid trafficking and induces large lipid droplet formation in intestinal absorptive epithelial cells.

Ezetimibe inhibits Niemann-Pick C1-like 1 (NPC1L1) protein, which mediates intracellular cholesterol trafficking from the brush border membrane to the endoplasmic reticulum, where chylomicron assembly takes place in enterocytes or in the intestinal absorptive epithelial cells. Cholesterol is a minor lipid constituent of chylomicrons; however, whether or not a shortage of cholesterol attenuates chylomicron assembly is unknown. The aim of this study was to examine the effect of ezetimibe, a potent NPC1L1 inhibitor, on trans-epithelial lipid transport, and chylomicron assembly and secretion in enterocytes. Caco-2 cells, an absorptive epithelial model, grown onto culture inserts were given lipid micelles from the apical side, and chylomicron-like triacylglycerol-rich lipoprotein secreted basolaterally were analyzed after a 24-h incubation period in the presence of ezetimibe up to 50 µM. The secretion of lipoprotein and apolipoprotein B48 were reduced by adding ezetimibe (30% and 34%, respectively). Although ezetimibe allowed the cells to take up cholesterol normally, the esterification was abolished. Meanwhile, oleic acid esterification was unaffected. Moreover, ezetimibe activated sterol regulatory element-binding protein 2 by approximately 1.5-fold. These results suggest that ezetimibe limited cellular cholesterol mobilization required for lipoprotein assembly. In such conditions, large lipid droplet formation in Caco-2 cells and the enterocytes of mice were induced, implying that unprocessed triacylglycerol was sheltered in these compartments. Although ezetimibe did not reduce the post-prandial lipid surge appreciably in triolein-infused mice, the results of the present study indicated that pharmacological actions of ezetimibe may participate in a novel regulatory mechanism for the efficient chylomicron assembly and secretion.

Redox-dependent PPARγ/Tnpo1 complex formation enhances PPARγ nuclear localization and signaling.

The nuclear receptor peroxisome proliferator-activated receptor (PPAR)γ has been implicated in the pathogenesis of various human diseases including fatty liver. Although nuclear translocation of PPARγ plays an important role in PPARγ signaling, details of the translocation mechanisms have not been elucidated. Here we demonstrate that PPARγ2 translocates to the nucleus and activates signal transduction through H2O2-dependent formation of a PPARγ2 and transportin (Tnpo)1 complex via redox-sensitive disulfide bonds between cysteine (Cys)176 and Cys180 of the former and Cys512 of the latter. Using hepatocyte cultures and mouse models, we show that cytosolic H2O2/Tnpo1-dependent nuclear translocation enhances the amount of DNA-bound PPARγ and downstream signaling, leading to triglyceride accumulation in hepatocytes and liver. These findings expand our understanding of the mechanism underlying the nuclear translocation of PPARγ, and suggest that the PPARγ and Tnpo1 complex and surrounding redox environment are potential therapeutic targets in the treatment of PPARγ-related diseases.

Clinical characterization of patients with primary aldosteronism plus subclinical Cushing's syndrome.

BACKGROUND: Primary aldosteronism (PA) plus subclinical Cushing's syndrome (SCS), PASCS, has occasionally been reported. We aimed to clinically characterize patients with PASCS who are poorly profiled. METHODS: A population-based, retrospective, single-center, observational study was conducted in 71 patients (age, 58.2 ± 11.2 years; 24 males and 47 females) who developed PA (n = 45), SCS (n = 12), or PASCS (n = 14). The main outcome measures were the proportion of patients with diabetes mellitus (DM), serum potassium concentration, and maximum tumor diameter (MTD) on the computed tomography (CT) scans. RESULTS: The proportion of DM patients was significantly greater in the PASCS group than in the PA group (50.0% vs. 13.9%, p <  0.05), without a significant difference between the PASCS and SCS groups. Serum potassium concentration was significantly lower in the PASCS group than in the SCS group (3.2 ± 0.8 mEq/L vs. 4.0 ± 0.5 mEq/L; p <  0.01), without a significant difference between the PASCS and PA groups. Among the 3 study groups of patients who had a unilateral adrenal tumor, MTD was significantly greater in the PASCS group than in the PA group (2.7 ± 0.1 cm vs. 1.4 ± 0.1 cm; p <  0.001), without a significant difference between the PASCS and SCS groups. CONCLUSIONS: Any reference criteria were not obtained that surely distinguish patients with PASCS from those with PA or SCS. However, clinicians should suspect the presence of concurrent SCS in patients with PA when detecting a relatively large adrenal tumor on the CT scans.

A Newly Integrated Model for Intestinal Cholesterol Absorption and Efflux Reappraises How Plant Sterol Intake Reduces Circulating Cholesterol Levels.

Cholesterol homeostasis is maintained through a balance of de novo synthesis, intestinal absorption, and excretion from the gut. The small intestine contributes to cholesterol homeostasis by absorbing and excreting it, the latter of which is referred to as trans-intestinal cholesterol efflux (TICE). Because the excretion efficiency of endogenous cholesterol is inversely associated with the development of atherosclerosis, TICE provides an attractive therapeutic target. Thus, elucidation of the mechanism is warranted. We have shown that intestinal cholesterol absorption and TICE are inversely correlated in intestinal perfusion experiments in mice. In this review, we summarized 28 paired data sets for absorption efficiency and fecal neutral sterol excretion, a surrogate marker of TICE, obtained from 13 available publications in a figure, demonstrating the inverse correlation were nearly consistent with the assumption. We then offer a bidirectional flux model that accommodates absorption and TICE occurring in the same segment. In this model, the brush border membrane (BBM) of intestinal epithelial cells stands as the dividing ridge for cholesterol fluxes, making the opposite fluxes competitive and being coordinated by shared BBM-localized transporters, ATP-binding cassette G5/G8 and Niemann-Pick C1-like 1. Furthermore, the idea is applied to address how excess plant sterol/stanol (PS) intake reduces circulating cholesterol level, because the mechanism is still unclear. We propose that unabsorbable PS repeatedly shuttles between the BBM and lumen and promotes concomitant cholesterol efflux. Additionally, PSs, which are chemically analogous to cholesterol, may disturb the trafficking machineries that transport cholesterol to the cell interior.

Intrinsic insulin secretion capacity might be preserved by discontinuing anti-programmed cell death protein 1 antibody treatment in 'anti-programmed cell death protein 1 antibody-induced' fulminant type 1 diabetes.

Intrinsic insulin secretion capacity may be preserved by discontinuing anti-PD-1 antibody treatment in 'anti-PD-1 antibody-induced'fulminant type 1 diabetes.

Effects of the Activation of Three Major Hepatic Akt Substrates on Glucose Metabolism in Male Mice.

Insulin suppresses glucose output from the liver via Akt activation; however, which substrate of Akt plays the major role in transducing this effect is unclear. We tested the postnatal expression of Akt-unresponsive, constitutively active mutants of three major Akt substrates widely considered to regulate glucose metabolism [i.e., FoxO1, PGC1α, and glycogen synthase kinase-3ß (GSK3ß)] using adenoviral gene delivery to the mouse liver. We performed physiological hyperinsulinemic-euglycemic clamp studies using these mice under awake and nonrestrained conditions with blood sampling via an arterial catheter. Hepatic expression of constitutively active FoxO1 induced significant hepatic and systemic insulin resistance. However, neither the expression of constitutively active PGC1α nor that of GSK3ß significantly changed insulin sensitivity. Simultaneous expression of all three mutants together induced no further insulin resistance compared with that of the FoxO1 mutant. The glycogen content in the liver was significantly reduced by constitutively active GSK3ß expression. In cultured hepatocytes, constitutively active PGC1α induced markedly stronger transcriptional enhancement of gluconeogenic key enzymes than did constitutively active FoxO1. From these results, we conclude that FoxO1 has the most prominent role in transducing insulin's effect downstream from Akt to suppress hepatic glucose output, involving mechanisms independent of the transcriptional regulation of key gluconeogenic enzymes.

Feminizing Adrenocortical Carcinoma with Distinct Histopathological Findings.

We herein present a 60-year-old man with adrenocortical carcinoma who had gynecomastia. An endocrinological examination revealed increased levels of serum estradiol and dehydroepiandrosterone-sulfate (DHEA-S) and reduced levels of free testosterone. Magnetic resonance imaging showed an adrenal tumor with heterogeneous intensity. Iodine-131 adosterol scintigraphy showed an increased uptake at the same site. Because feminizing adrenocortical carcinoma was suspected, right adrenalectomy was performed; the pathological diagnosis was adrenocortical carcinoma. The results of immunostaining indicated a virilizing tumor. Aromatase activity was identified on RT-PCR. As disorganized steroidogenesis is pathologically present in adrenocortical carcinoma, this diagnosis should be made with caution.

Aldo-keto reductase 1B10 promotes development of cisplatin resistance in gastrointestinal cancer cells through down-regulating peroxisome proliferator-activated receptor-γ-dependent mechanism.

Cisplatin (cis-diamminedichloroplatinum, CDDP) is one of the most effective chemotherapeutic drugs that are used for treatment of patients with gastrointestinal cancer cells, but its continuous administration often evokes the development of chemoresistance. In this study, we investigated alterations in antioxidant molecules and functions using a newly established CDDP-resistant variant of gastric cancer MKN45 cells, and found that aldo-keto reductase 1B10 (AKR1B10) is significantly up-regulated with acquisition of the CDDP resistance. In the nonresistant MKN45 cells, the sensitivity to cytotoxic effect of CDDP was decreased and increased by overexpression and silencing of AKR1B10, respectively. In addition, the AKR1B10 overexpression markedly suppressed accumulation and cytotoxicity of 4-hydroxy-2-nonenal that is produced during lipid peroxidation by CDDP treatment, suggesting that the enzyme acts as a crucial factor for facilitation of the CDDP resistance through inhibiting induction of oxidative stress by the drug. Transient exposure to CDDP and induction of the CDDP resistance decreased expression of peroxisome proliferator-activated receptor-γ (PPARγ) in MKN45 and colon cancer LoVo cells. Additionally, overexpression of PPARγ in the cells elevated the sensitivity to the CDDP toxicity, which was further augmented by concomitant treatment with a PPARγ ligand rosiglitazone. Intriguingly, overexpression of AKR1B10 in the cells resulted in a decrease in PPARγ expression, which was recovered by addition of an AKR1B10 inhibitor oleanolic acid, inferring that PPARγ is a downstream target of AKR1B10-dependent mechanism underlying the CDDP resistance. Combined treatment with the AKR1B10 inhibitor and PPARγ ligand elevated the CDDP sensitivity, which was almost the same level as that in the parental cells. These results suggest that combined treatment with the AKR1B10 inhibitor and PPARγ ligand is an effective adjuvant therapy for overcoming CDDP resistance of gastrointestinal cancer cells.

Ezetimibe Promotes Brush Border Membrane-to-Lumen Cholesterol Efflux in the Small Intestine.

Ezetimibe inhibits Niemann-Pick C1-like 1 (NPC1L1), an apical membrane cholesterol transporter of enterocytes, thereby reduces intestinal cholesterol absorption. This treatment also increases extrahepatic reverse cholesterol transport via an undefined mechanism. To explore this, we employed a trans-intestinal cholesterol efflux (TICE) assay, which directly detects circulation-to-intestinal lumen 3H-cholesterol transit in a cannulated jejunal segment, and found an increase of TICE by 45%. To examine whether such increase in efflux occurs at the intestinal brush border membrane(BBM)-level, we performed luminal perfusion assays, similar to TICE but the jejunal wall was labelled with orally-given 3H-cholesterol, and determined elevated BBM-to-lumen cholesterol efflux by 3.5-fold with ezetimibe. Such increased efflux probably promotes circulation-to-lumen cholesterol transit eventually; thus increases TICE. Next, we wondered how inhibition of NPC1L1, an influx transporter, resulted in increased efflux. When we traced orally-given 3H-cholesterol in mice, we found that lumen-to-BBM 3H-cholesterol transit was rapid and less sensitive to ezetimibe treatment. Comparison of the efflux and fractional cholesterol absorption revealed an inverse correlation, indicating the efflux as an opposite-regulatory factor for cholesterol absorption efficiency and counteracting to the naturally-occurring rapid cholesterol influx to the BBM. These suggest that the ezetimibe-stimulated increased efflux is crucial in reducing cholesterol absorption. Ezetimibe-induced increase in cholesterol efflux was approximately 2.5-fold greater in mice having endogenous ATP-binding cassette G5/G8 heterodimer, the major sterol efflux transporter of enterocytes, than the knockout counterparts, suggesting that the heterodimer confers additional rapid BBM-to-lumen cholesterol efflux in response to NPC1L1 inhibition. The observed framework for intestinal cholesterol fluxes may provide ways to modulate the flux to dispose of endogenous cholesterol efficiently for therapeutic purposes.

Identification of two nickel ion-induced genes, NCI16 and PcGST1, in Paramecium caudatum.

Here, we describe the isolation of two nickel-induced genes in Paramecium caudatum, NCI16 and PcGST1, by subtractive hybridization. NCI16 encoded a predicted four-transmembrane domain protein (∼16 kDa) of unknown function, and PcGST1 encoded glutathione S-transferase (GST; ∼25 kDa) with GST and glutathione peroxidase (GPx) activities. Exposing cells to cobalt chloride also caused the moderate upregulation of NCI16 and PcGST1 mRNAs. Both nickel sulfate and cobalt chloride dose dependently induced NCI16 and PcGST1 mRNAs, but with different profiles. Nickel treatment caused a continuous increase in PcGST1 and NCI16 mRNA levels for up to 3 and 6 days, respectively, and a notable increase in H2O2 concentrations in P. caudatum. NCI16 expression was significantly enhanced by incubating cells with H2O2, implying that NCI16 induction in the presence of nickel ions is caused by reactive oxygen species (ROS). On the other hand, PcGST1 was highly induced by the antioxidant tert-butylhydroquinone (tBHQ) but not by H2O2, suggesting that different mechanisms mediate the induction of NCI16 and PcGST1. We introduced a luciferase reporter vector with an ∼0.42-kb putative PcGST1 promoter into cells and then exposed the transformants to nickel sulfate. This resulted in significant luciferase upregulation, indicating that the putative PcGST1 promoter contains a nickel-responsive element. Our nickel-inducible system also may be applicable to the efficient expression of proteins that are toxic to host cells or require temporal control.

Fatty liver and anti-oxidant enzyme activities along with peroxisome proliferator-activated receptors γ and α expressions in the liver of Wilson's disease.

BACKGROUND: The mechanisms of liver damage and steatosis in Wilson's disease (WD) presenting accumulation of copper generating oxidants remain unclear. Recent studies have shown that peroxisome proliferator-activated receptors (PPARs), in particular PPARs α and γ, regulate fat content of the liver together with the anti-oxidant and anti-inflammation systems. However, such PPARs have never been studied in WD. METHODS: We examined PPARs along with the liver damage and steatosis of WD using liver specimens from affected patients exhibiting mild liver damage (group I, n = 5), moderate or greater liver damage (group II, n = 10) and fulminant hepatic failure (group III, n = 5), and from asymptomatic carriers (group H, n = 4). RESULTS: PPAR α expression was increased over the control levels in groups H and I but was decreased in groups II and III in parallel with the progression of liver damage (group H = I>II>III). PPAR γ expression was inversely increased (group H

A promoter in the novel exon of hPPARgamma directs the circadian expression of PPARgamma.

AIM: PPARgamma (peroxisome proliferator-activated receptor gamma) is a member of the nuclear receptor superfamily of ligand-activated transcription factors that regulate the expression of genes associated with lipid metabolism. Herein, we show that expression levels of the novel PPARgamma transcript exhibit circadian oscillation. To study the mechanisms controlling PPARgamma expression, a novel PPARgamma gene promoter was cloned and characterized. METHODS: We analyzed the novel PPARgamma promoter by luciferase reporter assays and gel shift analysis. RESULTS: Surprisingly, it was not an intron but rather the novel first exon of PPARgamma that was found to have functional minimal promoter activity. Luciferase reporter assays and gel shift assays revealed that the novel first exon is essential for novel PPARgamma promoter activation and that DBP (albumin gene D-site binding protein) and E4BP4 (E4 promoter A binding protein 4) bind directly to D-sites in the novel first exon. CONCLUSION: Our results demonstrate that the PAR-bZIP (bZIP, basic leucine zipper) family and E4BP4 are the main regulatory factors involved in oscillation of novel PPARgamma expression. This regulatory mechanism clearly differs from that of the circadian expression of PPARalpha.

Activating effect of momordin, extract of bitter melon (Momordica Charantia L.), on the promoter of human PPARdelta.

AIM: Bitter melon (Momordica charantia L.) is a common vegetable grown in Okinawa that has also been used recently in medicine for the treatment of diseases such as diabetes, hypertension, and dyslipidemia. Among Bitter melon extracts compounds, we focused on an extract known as momordin in the present study, to examine its effect on peroxisome-proliferator activated-receptor (PPAR) delta (also called PPARdelta in rodents) expression and promoter activity of the human PPARdelta gene. METHODS: A human PPARdelta promoter-reporter plasmid was made as a template from a BAC CLONE (RPCI-11C) containing a -3076 bp (BglI site) +74 bp (EcoRI site) sequence. Luciferase assay of PPARdelta promoter activity was performed using HepG2 cells. RESULTS: 10 and 25 nM Momordin significantly increased the expression of PPARdelta mRNA 1.5-fold (relative to the control). Moreover, 10 and 25 nM Momordin significantly increased PPARdelta promoter activity in a dose-dependent manner, reaching more than 1.5-fold relative to the control. CONCLUSION: Our present data obtained through successful cloning of the PPARdelta promoter demonstrate that PPARdelta production and activation are upregulated through PPARdelta promoter activity following momordin treatment.

Role of lysophosphatidylcholine in brush-border intestinal alkaline phosphatase release and restoration.

Intestinal alkaline phosphatase (IAP) is a brush-border membrane ectoenzyme (BBM-IAP) that is released into the lumen (L-IAP) after a high-fat diet. We examined the effects of oil feeding and the addition of mixed-lipid micelles on the formation of L-IAP in oil-fed rat intestine, Caco-2 cell monolayers, and mouse intestinal loops. We localized IAP in the duodenum of rats fed corn oil using fluorescence microscopy with enzyme-labeled fluorescence-97 as substrate. Four hours after oil feeding, L-IAP increased approximately 10-fold accompanied by the loss of BBM-IAP, consistent with BBM-IAP release. Rat IAP isozyme mRNAs progressively increased 4-6 h after oil feeding, followed by the increase of IAP activity in the subapical location at 6 h, consistent with the restoration of IAP protein. Postprandial lipid-micelle components, sodium taurocholate with or without oleic acid, mono-oleylglycerol, cholesterol, or lysophosphatidylcholine (lysoPC) were applied singly or as mixed-lipid micelles to the apical surface of polarized Caco-2 cell monolayers. LysoPC increased L-IAP >10-fold over basal release. LysoPC released IAP into the apical medium more than other intestinal brush-border enzymes, 5'-nucleotidase, sucrase, aminopeptidase N, and lactase, without comparable lactate dehydrogenase release or cell injury. LysoPC increased human IAP mRNA levels by 1.5-fold in Caco-2 cells. Luminally applied lysoPC also increased release of IAP preferentially in mouse intestinal loops. These data show that lysoPC accelerates the formation of L-IAP from BBM-IAP, followed by enhanced IAP synthesis, suggesting the role that lysoPC might play in the turnover of brush-border proteins.