Identification of herbal components as TRPA1 agonists and TRPM8 antagonists

Transient receptor potential (TRP) channels are non-selective cation channels that are implicated in analgesia, bowel motility, wound healing, thermoregulation, vasodilation and voiding dysfunction. Many natural products have been reported to affect the activity of TRP channels. We hypothesize that numerous traditional herbal medicines (THMs) might exert their pharmacological activity through modulating the activity of TRP channels. The present study aimed to evaluate the effects of flavonoid aglycones and their glycosides, which are the main components of many THMs, on the TRP channel subtypes. A Ca²⁺ influx assay was performed using recombinant human TRPA1, TRPV1, TRPV4 and TRPM8 cell lines. Our findings showed that flavonoid aglycones and glycycoumarin activated TRPA1. In particular, isoflavone and chalcone compounds displayed potent TRPA1 agonistic activity. Furthermore, flavone aglycones showed concomitant potent TRPM8 inhibiting activity. Indeed, flavone, isoflavone aglycones, non-prenylated chalcones and glycycoumarin were found to be TRPM8 inhibitors. Hence, flavonoid aglycones metabolized by lactase-phlorizin hydrolase and β-glucosidase in the small intestine or gut microbiota of the large intestine could generate TRPA1 agonists and TRPM8 antagonists.

     

Structure–Activity and Brain Kinetics Relationships of 18F-Labeled Benzimidazopyridine Derivatives as Tau PET Tracers

Noninvasive imaging of tau aggregates with a positron emission tomography (PET) tracer is useful for the diagnosis and staging of Alzheimer’s disease (AD). Recently, we found that benzimidazopyridine (BIP) is an attractive scaffold for developing PET and single photon computed emission tomography tracers targeting tau aggregates. In this study, we designed and synthesized five novel ¹⁸F-labeled compounds with various substituted groups or atoms at the 7-position of the BIP scaffold. In in vitro autoradiographic studies, all ¹⁸F-labeled BIP derivatives selectively bound to tau aggregates deposited in AD brain sections. On the other hand, the initial brain uptake of these compounds was affected by the type of substituted group or halogen atom introduced into the 7-position of the BIP scaffold. Among these compounds, [¹⁸F]Me-BIPF showed the highest brain uptake (6.79% ID/g at 2 min postinjection) and 2 min/60 min ratio (3.59). These results suggest that appropriate introduction of the substituted group or atom into the 7-position of the BIP scaffold may be effective for developing useful tau PET tracers.     

Social Frailty Has a Stronger Impact on the Onset of Depressive Symptoms than Physical Frailty or Cognitive Impairment: A 4-Year Follow-up Longitudinal Cohort Study

Objectives

To examine the association between each type of frailty status and the incidence rate of depressive symptoms among community-dwelling older adults.

Involvement of Ca²⁺ and ATP in enhanced gene delivery by bubble liposomes and ultrasound exposure

Recently, we reported the accelerated gene transfection efficiency of laminin-derived AG73-peptide-labeled polyethylene glycol-modified liposomes (AG73-PEG liposomes) and cell penetrating TAT-peptide labeled PEG liposomes using PEG-modified liposomes, which trap echo-contrast gas, "Bubble liposomes" (BLs), and ultrasound (US) exposure. BLs and US exposure were reported to enhance the endosomal escape of AG73-PEG liposomes, thereby leading to increased gene expression. However, the mechanism behind the effect of BLs and US exposure on endosomes is not well understood. US exposure was reported to induce an influx of calcium ions (Ca2?) by enhancing permeability of the cell membrane. Therefore, we examined the effect of Ca2? on the endosomal escape and transfection efficiency of AG73-PEG liposomes, which were previously enhanced by BLs and US exposure. For cells treated with EGTA, the endosomal escape and gene expression of AG73-PEG liposomes were not enhanced by BLs and US exposure. Similarly, transfection efficiency of the AG73-PEG liposomes in ATP-depleted cells was not enhanced. Our results suggest that Ca2? and ATP are necessary for the enhanced endosomal escape and gene expression of AG73-PEG liposomes by BLs and US exposure. These findings may contribute to the development of useful techniques to improve endosomal escape and achieve efficient gene transfection.     

Kupffer cell‐mediated exacerbation of methimazole‐induced acute liver injury in rats

Methimazole (MTZ), an anti‐thyroid drug, is known to cause liver injury in humans. It has been demonstrated that MTZ‐induced liver injury in Balb/c mice is accompanied by T helper (Th) 2 cytokine‐mediated immune responses; however, there is little evidence for immune responses associated with MTZ‐induced liver injury in rats. To investigate species differences in MTZ‐induced liver injury, we administered MTZ with a glutathione biosynthesis inhibitor, L‐buthionine‐S,R‐sulfoximine (BSO), to F344 rats and subsequently observed an increase in plasma alanine aminotransferase (ALT) and high‐mobility group box 1 (HMGB1), which are associated with hepatic lesions. The hepatic mRNA expression of innate immune‐related genes significantly increased in BSO‐ and MTZ‐treated rats, but the change in Th2‐related genes was not much greater than the change observed in the previous mouse study. Moreover, an increase in Kupffer cells and an induction of the phosphorylation of extracellular signal‐regulated kinase (ERK)/c‐Jun N‐terminal kinase (JNK) proteins were accompanied by an increase in Toll‐like receptor 4 (TLR4) expression, indicating that Kupffer cell activation occurs through HMGB1‐TLR4 signaling. To elucidate the mechanism of liver injury in rats, gadolinium chloride, which inactivates the function of Kupffer cells, was administered before BSO and MTZ administration. The gadolinium chloride treatment significantly suppressed the increased ALT, which was accompanied by decreased hepatic mRNA expression related to innate immune responses and ERK/JNK phosphorylation. In conclusion, Kupffer cell‐mediated immune responses are crucial factors for the exacerbation of MTZ‐induced liver injury in rats, indicating apparent species differences in the immune‐mediated exacerbation of liver injury between mice and rats. Copyright © 2015 John Wiley & Sons, Ltd.     

Synergistic interactions between footshocks and non-osmotic hypovolemia on vasopressin secretion in rats

The effects of i.p. injected hypertonic NaCl and polyethylene glycol on the magnitude of increase in plasma vasopressin after footshocks were studied in male rats, to determine whether hypovolemia and body fluid osmolality interact with noxious stimuli on vasopressin secretion. Present data have demonstrated that non-osmotic hypovolemia but not body fluid hyperosmolarity interact significantly and synergistically with footshocks to potentiate vasopressin secretion.     

Granulocyte-colony stimulating factor- and interleukin 6-producing diffuse deciduoid peritoneal mesothelioma.

An autopsy case of granulocyte colony-stimulating factor (G-CSF)- and interleukin-6 (IL-6)-producing diffuse deciduoid peritoneal mesothelioma is reported. The patient was a 70-year-old man with abdominal distension and weight loss in the year prior to his death. Laboratory data suggested severe inflammation with marked leukocytosis, thrombocytosis and elevated serum levels of C-reactive protein, G-CSF and IL-6. Imaging studies showed an expansive mass occupying the entire abdomen and pelvic cavity. Histological diagnosis of tissue taken by needle biopsy was difficult due to the unusual sarcomatoid-appearance of the tumor. In addition, there was severe infiltration of numerous neutrophilic leukocytes. An autopsy revealed that the diffuse peritoneal tumor had a fresh fishmeat-like appearance with focal mucinous degeneration and entirely encased the abdominal organs. Histological examination showed a sheet-like proliferation of tumor cells with large ovoid or polygonal cytoplasm, large atypical nuclei and obvious nucleoli. The tumor cells showed abundant glycogen and hyaluronic acid, and were immunoreactive to cytokeratin, calretinin, epithelial membrane antigen (EMA), CA-125, and focally to vimentin. The tumor cells were immunoreactive to G-CSF and IL-6. Electron microscopy revealed long, slender microvilli on the tumor cell surface. This tumor was diagnosed as a G-CSF- and IL-6-producing, diffuse deciduoid mesothelioma. We report this case with special reference to the differential diagnosis of deciduoid peritoneal mesothelioma with paraneoplastic syndrome.     

Rapid and sensitive mycoplasma detection system using image-based deep learning

Journal of Artificial Organs - A major concern in the clinical application of cell therapy is the manufacturing cost of cell products, which mainly depends on quality control. The mycoplasma test,...