BPB Reports

2021 - Vol. 4 No. 4

2021 - Vol. 4

Regular Article
Gastrointestinal Absorption of Ternatins, Polyacylated Anthocyanins Derived from Butterfly Pea (Clitoria ternatea L.) Petals in Rats Vol.4, No.4, p.136-141
Takashi Ichiyanagi , Masayuki Nashimoto , Norihiko Terahara
Received: July 28, 2021
Accepted: August 19, 2021
Released: September 02, 2021
Abstract Full Text PDF[1M]

Ternatins, polyacylated anthocyanins that contain two or more aromatic acyl groups, are found in the petals of butterfly pea (Clitoria ternatea L.). We examined the gastrointestinal absorption of ternatins in rats after oral administration of the extract of the butterfly pea petals. Ingested ternatins were absorbed rapidly in the gastrointestinal tract in their original acylated forms. Nine ternatins were detected, together with preternatin A3, in rat blood plasma at 15 min after oral administration. After a single oral dose of 0.0527 mmol/kg ternatin, the maximum plasma concentration and area under the plasma concentration curve for total ternatin was 0.141 ± 0.035 μM and 16.398 ± 1.542 μM·min, respectively, during the 8-h period post-administration. The absorption of ternatins in blood plasma tended to negatively correlate with increasing order of molecular weight; however, ternatins carrying symmetrical substitution patterns and glucosyl terminals on the both side chains at the 3' and 5' positions of the aglycone were exceptionally bioavailable.

Regular Article
The Effect of Medroxyprogesterone Acetate on the Secretion of Lipoprotein Lipase in Mouse Mammary Tumor Cells Vol.4, No.4, p.130-135
Tomoyasu Fujii , Jun Kamishikiryo , Tetsuo Morita
Received: July 07, 2021
Accepted: August 20, 2021
Released: August 31, 2021
Abstract Full Text PDF[1M]

Progesterone (P4) is a corpus luteum hormone associated with the development of the mammary gland and uterus. The actions of P4 on lipid metabolism in breast cancer are unclear. In this study, we investigated medroxyprogesterone acetate (MPA) on the secretion of lipoprotein lipase (LPL) from mouse mammary tumor FM3A cells. The tumor cells were incubated with MPA and other agents. The treated cells were used in the mitogen-activated protein kinase (MAPK) and LPL activity assay. The supernatant was used in the LPL activity assay and western blotting. The increased secretion of LPL in the tumor cells treated with MPA was observed. The MPA-stimulated secretion of LPL was suppressed by a protein kinase A (PKA) inhibitor. The activity of MAPK increased in the tumor cells treated with MPA, and various MAPK inhibitors suppressed the stimulatory secretion of LPL. The effect of MPA on LPL secretion was markedly suppressed by an inhibitor of the mechanistic target of rapamycin complex (mTORC) 1 and 2, KU0063794, but not the mTORC1 inhibitor, rapamycin. Furthermore, a small interfering RNA-mediated decrease in Rictor's expression, a pivotal component of mTORC2, suppressed the stimulatory secretion of LPL. These results suggest that the stimulatory secretion of LPL in the tumor cells treated with MPA is closely associated with activation of mTORC2, possibly via the MAPK signaling associated with PKA activation.

Regular Article
Association between Whole Blood Manganese and Dry Skin in Hemodialysis Patients Vol.4, No.4, p.124-129
Masataka Deguchi , Hirofumi Machida , Hiroyuki Yasui , Jun Hiraoka , Keigo Nishida , Keiichi Hiramoto , Hidehiko Jose , Misao Takeuchi , Kazuya Ooi
Received: July 18, 2021
Accepted: July 20, 2021
Released: August 18, 2021
Abstract Full Text PDF[874K]

Background and aim: Abnormalities in blood metal concentrations and pruritus occur frequently in hemodialysis patients. Pruritus significantly impairs the quality of life for these patients, and may be related to abnormal blood metal concentrations. Therefore, we measured the blood metal concentrations in hemodialysis patients and non-dialysis control patients to examine the relationship between blood metal level, pruritus, and skin condition. Methods: Hemodialysis patients were divided into “scratching” and “non-scratching” groups based on the severity of their symptoms. Blood was collected and the skin condition was measured at the start of hemodialysis in the patient group. Concentrations of metals such as magnesium, calcium, manganese, iron, copper, and zinc in serum and whole blood were determined by an inductively coupled plasma-mass spectrometer. Skin condition was assessed by measuring transepidermal water loss and stratum corneum moisture content. Results: The whole blood manganese level in hemodialysis patients was 8 times higher than that in non-dialysis patients (168 ± 42 ng/mL vs 22 ± 15 ng/mL), and a negative correlation was found between manganese level and stratum corneum moisture content. The stratum corneum moisture content in the scratching group was significantly lower than that in the non-scratching group. Conclusion: Patients with higher levels of whole blood manganese exhibited dry skin.

Extracellular Elaidate, a Trans Fatty Acid, Tends to be Incorporated into Triglycerides and Incorporated Elaidate is Released by Lipolysis Vol.4, No.4, p.120-123
Kenichi Ishibashi , Gen-ichi Atsumi
Received: July 21, 2021
Accepted: July 22, 2021
Released: August 18, 2021
Abstract Full Text PDF[1M]

Intake of elaidate, an industrially produced trans fatty acid, is associated with the development of cardiovascular disease. Recently, we revealed that persistent exposure to elaidate impairs the insulin responsiveness of adipocytes. Moreover, extracellular elaidate is incorporated into phospholipids and triglycerides and exists mainly as triglycerides in adipocytes. Because fatty acids in adipocytes are not only used as an energy source but also released as cytokines to regulate cellular function and whole-body metabolism, we hypothesized that elaidate is released from adipocytes. Here, we examined the intracellular behavior of elaidate to explain that incorporated elaidate exists mainly as triglycerides, and whether it is released from adipocytes. Extracellular elaidate was incorporated into triglycerides rather than phospholipids, and elaidate incorporated into triglycerides did not decrease during the study period. Under lipolytic stimulation, incorporated elaidate—together with other fatty acids—was released from adipocytes. These results imply that adipocytes act as a reservoir of elaidate.

Inhibitory Activity and Proposed Binding Model of γ-Glutamyl Cysteine, the Precursor of Glutathione, on Angiotensin Converting Enzyme Vol.4, No.4, p.116-119
Chisato Okajima , Naoki Imakawa , Kazuya Nagano , Masayoshi Arai , Mitsuhiro Arisawa , Misa Muraoka , Hirofumi Tsujino , Yoshihiko Hirata , Kazumasa Hirata
Received: June 11, 2021
Accepted: July 21, 2021
Released: August 13, 2021
Abstract Full Text PDF[1M]

Owing to their various physiological activities, thiol compounds, such as l-cysteine with UV-protection properties and captopril that inhibits the catalytic activity of angiotensin converting enzyme (ACE), are currently used as supplements and pharmaceuticals. Glutathione (GSH) plays an important role in intracellular protective effects and is currently used for the treatment of cataract and detoxification from metal poisoning. In contrast to GSH, the GSH precursor γ-glutamyl cysteine (γ-EC) has been reported to exhibit neuroprotective effects, thus making it an attractive key biological protective molecule. However, its characteristics are largely unknown. Here, we evaluated the ACE inhibitory function of γ-EC and its mechanism by comparing it with that of GSH in vitro. ACE inhibitory analysis showed that the IC50 of GSH and γ-EC against ACE were 8.3 μM and 3.9 × 102 μM, respectively. These data suggested that γ-EC exerted ACE inhibitory activity, but it was weaker than that of GSH. Docking simulation showed that the ACE inhibitory activity of both compounds was due to the interaction of their carboxyl groups of Glu with Zn2+ in the active center of ACE. Moreover, GSH could fit more compactly in the pocket of ACE, forming more hydrogen bonds with the enzyme than γ-EC. By analyzing its kinetics and in vivo efficacy, we hope that γ-EC could be used as a promising compound for lowering blood pressure in applications with moderate activity, such as functional foods.

Methotrexate Induces Hyperplasia of Enterochromaffin Cells in Mouse Jejunum Vol.4, No.4, p.112-115
Takuji Machida , Airi Tanaka , Megumi Kobayashi , Kohei Imai , Masahiko Hirafuji , Kenji Iizuka
Received: May 12, 2021
Accepted: July 26, 2021
Released: August 13, 2021
Abstract Full Text PDF[1M]

5-Hydroxytryptamine (5-HT) is synthesized by L-tryptophan hydroxylase (TPH) and is stored mainly in enterochromaffin cells of the mucosal epithelium. We previously reported that administration of methotrexate, an anticancer agent, to rats caused hyperplasia of enterochromaffin cells, and nitric oxide (NO) might be involved in the underlying mechanism. The aim of this study was to clarify the effect of methotrexate on hyperplasia of enterochromaffin cells in mice. C57BL/6J mice were intraperitoneally injected with methotrexate or saline as a control. Methotrexate caused an increase in the number of TPH-expressing cells (i.e., enterochromaffin cells) in the jejunum. Methotrexate also increased inducible, but not constitutive, NOS mRNA expression. Our results indicate that methotrexate potentiates 5-HT synthesis in mice, as we previously found in rats.

Regular Article
Elevated Expression of CELSR1 is Associated with Peritoneal Metastasis in Human Scirrhous Gastric Cancers Vol.4, No.4, p.103-111
Toshifumi Hara , Yuri Nomura , Masaaki Hattori , Keichiro Mihara , Kazuyoshi Yanagihara , Yoshifumi Takei
Received: July 17, 2021
Accepted: July 19, 2021
Released: August 13, 2021
Abstract Full Text PDF[4M]

Cancer metastasis is the leading cause of death in patients with any type of solid cancer. To develop effective cancer treatments, it is essential to understand the molecular mechanisms underlying cancer metastasis. Previously we established peritoneal metastasis cell models derived from human scirrhous gastric cancer patients. In this article, we focus on the CELSR1 gene, which is involved in Wnt signaling but whose association with peritoneal metastasis is still unclear. We unveiled gene alterations and the prognostic relevance of the CELSR1 gene in cancer patients by analyzing public resources for cancer genomic and patient cohorts. RT-qPCR and immunoblot analyses revealed that CELSR1 expression was significantly elevated in our cell lines, which had high peritoneal metastatic property, compared with their parental cell lines, which had lower peritoneal metastatic property. Some of the gene alterations in the coding region of CELSR1 were observed in our metastatic cell lines, but they were not associated with the metastatic property or with patient prognosis. Knockdown of CELSR1 via the shRNA technique significantly decreased migration and invasion in the cell lines having high peritoneal metastatic property, whereas the knockdown did not significantly affect proliferation. These results show that CELSR1 plays an important role in peritoneal metastasis and that CELSR1 is a novel peritoneal metastasisassociated gene. The results also suggest that CELSR1 is a proper molecular target for therapy against peritoneal metastasis of scirrhous gastric cancers.

Immunomodulatory Activity of an Aqueous Extract of Mycelium of an Endophytic-Like Fungus, Ustilago esculenta Vol.4, No.4, p.98-102
Makoto Tsuiji , Junko Nagasaka , Yoshimasa Yajima , Keita Nishiumi , Yasutaka Kojima , Miho Amemiya , Wakana Ogura , Takaaki Moriyama , Tomoko Sakai , Teruaki Oku , Tsutomu Tsuji
Received: March 08, 2021
Accepted: June 30, 2021
Released: July 30, 2021
Abstract Full Text PDF[1M]

An aqueous extract of mycelium of Ustilago esculenta, an endophytic-like fungus, was intraperitoneally administered to mice with a model antigen (NP-BSA) and aluminum adjuvant (Alum). Blood was periodically collected from the tail veins of the mice, and the antibody titer against NP-BSA and/or BSA in the serum was measured by ELISA. The aqueous U. esculenta extract had no significant effect on the IgM and IgG antibody titers in the primary response but greatly lowered those in the secondary response. When the antibody titers of the IgG subtypes were separately measured, the ratios of IgG2b/IgG1 and IgG2c/IgG1 titers in the mice treated with the U. esculenta extract were markedly lower than those in the control mice treated with NP-BSA/Alum. The Bio-PlexTM cytokine assay revealed that the concentrations of interferon-γ (IFN-γ) and interleukin-12 (IL-12 (p70)) in peripheral blood from U. esculenta extract-treated mice were decreased as compared with those from the control mice three weeks after the initial immunization. These results suggest that the aqueous extract of mycelium of U. esculenta suppressed antibody production in the secondary response and that changes of the Th1/Th2 balance were involved in this process.