Meal Ingestion of Ceraceomyces tessulatus Strain BDM-X (Agaricomycetes) Protects against Nonalcoholic Steatohepatitis in Mice.

Nonalcoholic steatohepatitis (NASH) is becoming the most common cause of hepatocellular carcinoma (HCC) in developed countries. Oxidative stress plays a major role in the pathogenesis of NASH due to steatosis; hence, novel therapeutic approaches might include natural antioxidants. Ceraceomyces tessulatus strain Basidiomycetes-X (BDM-X), a novel edible mushroom, possesses potent antioxidant activity. This study aimed to investigate the hepato-protective effect of C. tessulatus BDM-X in a novel NASH-HCC mouse model. To prepare this animal model, 2-day-old C57BL/6J male pups were exposed to low-dose streptozotocin (STZ); at 4 weeks of age, they were randomly divided into two groups. The NASH group (NASH) received a high-fat diet (HFD32) up to 14 weeks of age; the C. tessulatus BDM-X group (BDM-X) received HFD32 up to age 10 weeks, followed by HFD32 + 20% BDM-X (percent weight per weight in the diet) up to age 14 weeks. Mice not treated with STZ and fed a normal diet served as a control group. We found that C. tessulatus BDM-X improved serum aminotransferase levels as well as histopathological features such as steatosis, inflammatory foci, and pericellular fibrosis in NASH mice. Hepatic protein expression of sterol regulatory element binding protein isoform SREBP-1 and peroxisome proliferator-activated receptor PPARα was significantly increased in NASH mice. C. tessulatus BDM-X treatment normalized the expression of both proteins. Our data suggest that C. tessulatus BDM-X may protect the liver against lipogenesis in NASH-HCC mice.

Extremely low-frequency electric field suppresses not only induced stress response but also stress-related tissue damage in mice.

Although extremely low-frequency electric fields (ELF-EF) have been utilised for therapeutic purposes, the biological effect and the underlying mechanism of ELF-EF have not been elucidated. Here, we developed a mouse model of immobilisation-induced increase in glucocorticoid (GC) to evaluate the effect of ELF-EF. Mice were exposed to 50-Hz 10 kV/m EF via a parallel plate electrode and immobilised as needed. The ELF-EF suppressed the immobilisation-induced increase in blood GC level. Here, the results of 32 tests using the model were pooled and analysed. The suppressive effect of ELF-EF on immobilisation-induced increase in GC was reproduced, and the GC level was slightly higher in the ELF-EF-treated mice than in the sham-controlled mice, a novel observation. The immobilisation-induced increase in lactate dehydrogenase, glutamic oxaloacetic transaminase, and glutamic pyruvic transaminase, markers of tissue damage, was suppressed by co-treatment with EF in the biochemical tests using the same plasma sample. In the metabolome analysis, the changes in corticosterones, leukotrienes, and hydroxyeicosatetraenoic acids, markers of inflammation, showed a pattern similar to that of the plasma GC level. Thus, ELF-EF suppresses the stress response that causes an increase in the GC level and slightly promotes GC production in the absence of stress. Moreover, the suppressive effect of ELF-EF on induced stress response might be involved in stress-induced tissue damage or inflammation in immobilised mice. Overall, the model and the data help explore the biological effect of ELF-EF and explain the stress-relieving effect of EF. They would be useful in determining the medical applications of EF in humans and animals.

Soy Isoflavone Genistein Inhibits an Axillary Osmidrosis Risk Factor ABCC11: In Vitro Screening and Fractional Approach for ABCC11-Inhibitory Activities in Plant Extracts and Dietary Flavonoids.

Axillary osmidrosis (AO) is a common chronic skin condition characterized by unpleasant body odors emanating from the armpits, and its aetiology is not fully understood. AO can seriously impair the psychosocial well-being of the affected individuals; however, no causal therapy has been established for it other than surgical treatment. Recent studies have revealed that human ATP-binding cassette transporter C11 (ABCC11) is an AO risk factor when it is expressed in the axillary apocrine glands-the sources of the offensive odors. Hence, identifying safe ways to inhibit ABCC11 may offer a breakthrough in treating AO. We herein screened for ABCC11-inhibitory activities in 34 natural products derived from plants cultivated for human consumption using an in vitro assay system to measure the ABCC11-mediated transport of radiolabeled dehydroepiandrosterone sulfate (DHEA-S-an ABCC11 substrate). The water extract of soybean (Glycine max) was found to exhibit the strongest transport inhibition. From this extract, via a fractionation approach, we successfully isolated and identified genistein, a soy isoflavone, as a novel ABCC11 inhibitor with a half-maximal inhibitory concentration value of 61.5 µM. Furthermore, we examined the effects of other dietary flavonoids on the ABCC11-mediated DHEA-S transport to uncover the effects of these phytochemicals on ABCC11 function. While further human studies are needed, our findings here about the natural compounds will help develop a non-surgical therapy for AO.

Omega-3 Polyunsaturated Fatty Acids Inhibit the Function of Human URAT1, a Renal Urate Re-Absorber.

The beneficial effects of fatty acids (FAs) on human health have attracted widespread interest. However, little is known about the impact of FAs on the handling of urate, the end-product of human purine metabolism, in the body. Increased serum urate levels occur in hyperuricemia, a disease that can lead to gout. In humans, urate filtered by the glomerulus of the kidney is majorly re-absorbed from primary urine into the blood via the urate transporter 1 (URAT1)-mediated pathway. URAT1 inhibition, thus, contributes to decreasing serum urate concentration by increasing net renal urate excretion. Here, we investigated the URAT1-inhibitory effects of 25 FAs that are commonly contained in foods or produced in the body. For this purpose, we conducted an in vitro transport assay using cells transiently expressing URAT1. Our results showed that unsaturated FAs, especially long-chain unsaturated FAs, inhibited URAT1 more strongly than saturated FAs. Among the tested unsaturated FAs, eicosapentaenoic acid, α-linolenic acid, and docosahexaenoic acid exhibited substantial URAT1-inhibitory activities, with half maximal inhibitory concentration values of 6.0, 14.2, and 15.2 µM, respectively. Although further studies are required to investigate whether the ω-3 polyunsaturated FAs can be employed as uricosuric agents, our findings further confirm FAs as nutritionally important substances influencing human health.

Effect of vegetable oils on the experimental infection of mice with Trypanosoma congolense.

Vegetable oils are frequently used as solvents for lipophilic materials; accordingly, the effects of their components should be considered in animal experiments. In this study, the effects of various vegetable oils on the course of Trypanosoma congolense infection were examined in mice. C57BL/6J mice were orally administered four kinds of oils (i.e., coconut oil, olive oil, high oleic safflower oil, and high linoleic safflower oil) with different fatty acid compositions and infected with T. congolense IL-3000. Oil-treated mice infected with T. congolense showed significantly higher survival rates and lower parasitemia than those of control mice. Notably, coconut oil, which mainly consists of saturated fatty acids, delayed the development of parasitemia at the early stage of infection. These results indicated that vegetable oil intake could affect T. congolense infection in mice. These findings have important practical implications; for example, they suggest the potential effectiveness of vegetable oils as a part of the regular animal diet for controlling tropical diseases and indicate that vegetable oils are not suitable solvents for studies of the efficacy of lipophilic agents against T. congolense.

Gender and Age Differences in the Suppressive Effect of a 50 Hz Electric Field on the Immobilization-Induced Increase of Plasma Glucocorticoid in Mice.

We developed an experimental system to characterize the suppressive effect of extremely low-frequency (ELF) electric fields (EFs) on the stress response. We assessed differences in the EF effects by age and gender. Control, EF-alone, immobilization-alone, and co-treated groups were subjected to an EF (50 Hz, 10 kV/m). Co-treated mice were exposed to the EF for 60 min, with immobilization during the latter half. Our results indicate that the suppressive effects of ELF EFs on the stress response in immobilized mice occur regardless of gender or age. As stress plays an important role in the onset and progression of various diseases, these findings may have broad implications for understanding the efficacy of EFs in animal, and perhaps human, health. Bioelectromagnetics. 2020;41:156-163. © 2019 Bioelectromagnetics Society.

[Analysis of the Risk Factors Associated with Minor Bleeding in Patients with Venous Thromboembolism during Treatment with Direct Oral Anticoagulants].

Direct oral anticoagulants (DOACs) are safe and efficacious when compared to warfarin for patients with venous thromboembolism (VTE). However, bleeding is a major side effect of anticoagulant therapy in VTE patients. Discontinuation of the DOACs associated to adverse events such as bleeding. The HAS-BLED score predicts warfarin-associated hemorrhage. However, little is known about risk factors for DOAC-associated minor bleeding in VTE patients. We aimed to identify risk factors for minor bleeding in VTE patients that were treated with edoxaban, rivaroxaban, or apixaban. We retrospectively evaluated the data of 212 VTE patients who received treatment with a DOAC. The study endpoint was defined as the occurrence of minor bleeding. Logistic regression analysis was used to determine risk factors that were significantly associated with minor bleeding. A total of 36 (17.0%) patients experienced minor bleeding, with rates of 15.7%, 0%, and 21.3% for edoxaban, rivaroxaban, and apixaban, respectively. In the multivariate analysis, bleeding history or predisposition [odds ratio (OR) 6.083, 95% confidence interval (CI) 2.131-17.364, p=0.001] and cancer (OR 6.397, 95% CI 2.858-14.317, p<0.001) were significantly associated with minor bleeding. Bleeding history or predisposition and cancer were the most important risk factors for DOAC-induced minor bleeding in VTE patients in this study. To continue anticoagulant therapy of the DOACs, further management systems by minor bleeding risk factors for patients with VTE will be required.

Feasibility of transnasal flexible carbon dioxide laser surgery for laryngopharyngeal lesions.

OBJECTIVE: The fiber-guided carbon dioxide (CO2) laser is a useful device for laryngopharyngeal surgery. The flexible CO2 wave-guide laser has been developed and commercially available for several years. However, the transnasal use of CO2 flexible wave-guided laser surgery through the instrument channel of a flexible endoscope (CO2 TNFLS) is not permitted in Japan. This feasibility study aimed to assess the value and the safety of an in-office CO2 TNFLS procedure. METHODS: Patients with small laryngopharyngeal diseases were enrolled from June 2015. Eligible patients had indications with lesions generally localized superficial lesions such as the benign tumor, leukoplakia, and premalignant lesion-like carcinoma in situ (CIS). Patients were locally well anesthetized using xylocaine. After removing as much of the lesion(s) as possible with flexible forceps, the remainder of the lesions were evaporated using CO2 TNFLS through the instrument channel of a flexible endoscope under local anesthesia. RESULTS: Eighteen surgeries involving 13 patients, including 9 papilloma (7 recurrent respiratory papilloma [RRP]), 2 carcinoma in situ, 1 leukoplakia, and 1 large epiglottic cyst), were performed. Four patients with RRP required multiple surgeries. Except for 3 patients with RRP, all patients achieved disease control without additional intervention. All procedures were completed with no severe adverse events. CONCLUSION: Office-based CO2 TNFLS is safe and feasible for patients with laryngopharyngeal pathologies. It is especially valuable for RRP patients with small lesions to avoid surgery under general anesthesia.

Effects of Osthol Isolated from Cnidium monnieri Fruit on Urate Transporter 1.

(1) Background: Crude drugs used in traditional Japanese Kampo medicine or folk medicine are major sources of new chemical entities for drug discovery. We screened the inhibitory potential of these crude drugs against urate transporter 1 (URAT1) to discover new drugs for hyperuricemia. (2) Methods: We prepared the MeOH extracts of 107 different crude drugs, and screened their inhibitory effects on URAT1 by measuring the uptake of uric acid by HEK293/PDZK1 cells transiently transfected with URAT1. (3) Results: We found that the extract of the dried mature fruit of Cnidium monnieri inhibited urate uptake via URAT1. We isolated and identified osthol as the active ingredient from this extract. Osthol noncompetitively inhibited URAT1 with an IC50 of 78.8 µM. We evaluated the effects of other coumarins and found that the prenyl group, which binds at the 8-position of coumarins, plays an important role in the inhibition of URAT1. (4) Conclusions: Cnidium monnieri fruit may be useful for the treatment of hyperuricemia or gout in traditional medicine, and its active ingredient, osthol, is expected to be a leading compound for the development of new drugs for hyperuricemia.

Characterization of the suppressive effects of extremely-low-frequency electric fields on a stress-induced increase in the plasma glucocorticoid level in mice.

We recently suggested that an increase in the plasma glucocorticoid (GC) level in immobilized mice is suppressed by a 50-Hz electric field (EF) in an EF strength-dependent manner. The present study aimed to assess the anti-stress effect of EFs in three scenarios: exposure to an EF of either 50 or 60 Hz, which are the standard power frequencies in most regions; varying levels of environmental brightness during EF exposure; complete or partial shielding of the mouse from the EF. We compared the GC levels and blood parameters among control, EF-alone, immobilization-alone, and co-treatment groups. There was no difference between EFs of 50 and 60 Hz in terms of the suppression of the immobilization-induced increase in GC, that is, the anti-stress effect upon EF exposure. Examination of the effects of three environmental illuminance levels, 0, 200, and 490 lux, revealed that the effect of the EF was influenced by environmental illuminance. Shielding of the mice from the EF by wrapping the animals with an electrically conductive sheet inhibited the EF effect, which showed a negative correlation with the area shielded. Hence, environmental illuminance and the body area exposed to the EF might influence the effects of an EF on stress-induced increases in plasma GC levels in mice. Because stress plays an important role in the onset and progression of various diseases, these findings may have broad implications for understanding the efficacy of EFs in health. Bioelectromagnetics. 39:516-528, 2018 © 2018 Wiley Periodicals, Inc.

Effects of 5-aminolevulinic acid supplementation on home-based walking training achievement in middle-aged depressive women: randomized, double-blind, crossover pilot study.

Depressive patients often experience difficulty in performing exercise due to physical and psychological barriers. We examined the effects of 5-aminolevulinic acid (ALA) with sodium ferrous citrate (SFC) supplementation during home-based walking training in middle-aged depressive women. Nine outpatients [53 ± 8 (SD) yr] with major depressive disorder participated in the pilot study with randomized, placebo-controlled, double-blind crossover design. They underwent two trials for 7 days, each performing interval walking training (IWT) with ALA + SFC (ALA + SFC) or placebo supplement intake (PLC) intermittently with >a 10-day washout period. For the first 6 days of each trial, exercise intensity for IWT was measured by accelerometry. Before and after each trial, subjects underwent a graded cycling test, and lactate concentration in plasma ([Lac-]p), oxygen consumption rate ([Formula: see text]), and carbon dioxide production rate ([Formula: see text]) were measured with depression severity by the Montgomery-Åsberg Depression Rating Scale (MADRS). We found that the increases in [Lac-]p, [Formula: see text] and [Formula: see text] during the test were attenuated only in ALA + SFC ([before vs. after] × workload; all, P < 0.01), accompanied by increased training days, impulse, and time at fast walking during IWT (all, P < 0.05) with decreased MADRS-score (P = 0.001). Thus, ALA + SFC supplementation increased IWT achievement to improve depressive symptoms in middle-aged women.

Curcumin reduces the risk of chronic kidney damage in mice with nonalcoholic steatohepatitis by modulating endoplasmic reticulum stress and MAPK signaling.

Developing confirmation recommends that in patients with dynamic type of NAFLD, particularly nonalcoholic steatohepatitis (NASH) may have the pathogenic parts in the advancement of kidney damage. In this study we have examined the impact of curcumin on NASH instigated chronic kidney damage (CKD) and the putative mechanisms. To prepare this NASH model, neonatal C57BL/6J male mice were exposed to low-dose streptozotocin (STZ) and were fed high-fat diet (HFD) at the age of 4weeks and continued up to 14weeks, curcumin was given at 100mg/kg dose by oral gavage daily after 10weeks of STZ injection and continued for 4weeks along with HFD feeding. NASH incited mice demonstrated nephrotoxicity as proved by declining renal capacity, which was evaluated by measuring blood urea nitrogen and creatinine in serum and histopathological variations from the norm. These progressions were switched by curcumin treatment, which brought about huge change in renal capacity. Furthermore, curcumin markedly decreased NAD(P)H oxidase subunits (p67phox, p47phox, p22phox), nitrotyrosine and CYP2E1 renal protein expression as well as reduced pro-inflammatory cytokine expression (TNFα, IL-1ß, IFNγ). Renal protein expression of mitogen activated protein kinases (MAPKs) (p-JNK, p-ERK1/2) and glucose regulated protein 78, CHOP were increased in NASH induced mice and curcumin treatment attenuated these increased expressions. In addition, curcumin treatment also decreased the apoptosis signaling proteins (cleaved caspase-3, cleaved caspase-12) in the NASH kidney. Taken together, our results suggest that curcumin preserves the renal function, probably by attenuating the ER stress mediated MAPK signaling.

Dose-dependent artificial prolongation of prothrombin time by interaction between daptomycin and test reagents in patients receiving warfarin: a prospective in vivo clinical study.

BACKGROUND: Daptomycin has been reported to cause artificial prolongation of prothrombin time (PT) by interacting with some test reagents of PT. This prolongation was particularly prominent with high concentrations of daptomycin in vitro. However, whether this prolongation is important in clinical settings and the optimal timing to assess PT remain unclear. METHODS: A prospective clinical study was conducted with patients who received daptomycin for confirmed or suspected drug-resistant, gram-positive bacterial infection at a university hospital in Japan. PT at the peak and trough of daptomycin was tested using nine PT reagents. Linear regression analyses were used to examine the difference in daptomycin concentration and the relative change of PT-international normalized ratios (PT-INR). RESULTS: Thirty-five patients received daptomycin (6 mg/kg). The mean ± standard deviation of the trough and peak concentrations of daptomycin were 13.5 ± 6.3 and 55.1 ± 16.9 µg/mL, respectively. Twelve patients (34%) received warfarin. With five PT reagents, a significant proportion of participants experienced prolongation of PT-INR at the daptomycin peak concentration compared to the PT-INR at the trough, although the mean relative change was less than 10%. None of the participants clinically showed any signs of bleeding. A linear, dose-dependent prolongation of PT was observed for one reagent [unadjusted coefficient ß 3.1 × 10-3/µg/mL; 95% confidence interval (CI) 2.3 × 10-5-6.3 × 10-3; p = 0.048]. When patients were stratified based on warfarin use, this significant linear relationship was observed in warfarin users for two PT reagents (adjusted coefficient ß, 6.4 × 10-3/µg/mL; 95% CI 3.5 × 10-3-9.3 × 10-3; p < 0.001; and adjusted coefficient ß, 8.3 × 10-3/µg/mL; 95% CI 4.4 × 10-3-1.2 × 10-2; p < 0.001). In non-warfarin users, this linear relationship was not observed for any PT reagents. CONCLUSIONS: We found that a higher concentration of daptomycin could lead to artificial prolongation of PT-INR by interacting with some PT reagents. This change may not be clinically negligible, especially in warfarin users receiving a high dose of daptomycin. It may be better to measure PT at the trough rather than at the peak daptomycin concentration.

Configuration-dependent variability of the effect of an electric field on the plasma glucocorticoid level in immobilized mice.

We recently reported that an immobilization stress-induced increase in glucocorticoid (GC) level was suppressed in mice exposed to an electric field (EF) of 50 Hz in a kV/m-dependent manner. In this study, we investigated the reproducibility of the suppressive effect induced by EF exposure by varying the voltage and distance between the electrodes (0.5 kV/50 mm, 1 kV/100 mm, 2 kV/200 mm) and comparing the effects on the plasma GC level. In addition, the effect of mice being in contact with the lower electrode or not was compared at 1 kV/100 mm. Immobilization-induced GC levels were significantly decreased in mice exposed to an EF at 1 kV/100 mm for 60 min (P < 0.01), but not in mice exposed to 0.5 kV/50 mm or 2 kV/200 mm. Furthermore, the suppressive effect of the 1 kV/100 mm EF was canceled when a polypropylene sheet (0.1 mm thick) was placed between the animal and lower electrode. Our findings corroborated that an EF of 10 kV/m inhibits stress-induced changes in the endocrine system in mice and demonstrated that this effect depends on the configuration of the EF exposure system, even when the EF strength remains the same. Bioelectromagnetics. 38:265-271, 2017. © 2017 Wiley Periodicals, Inc.

Curcumin ameliorates liver damage and progression of NASH in NASH-HCC mouse model possibly by modulating HMGB1-NF-κB translocation.

Curcumin, a phenolic compound, has a wide spectrum of therapeutic effects such as antitumor, anti-inflammatory, anti-cancer and so on. The study aimed to investigate the underlying mechanisms of curcumin to protect liver damage and progression of non-alcoholic steatohepatitis (NASH) in a novel NASH-hepatocellular carcinoma (HCC) mouse model. To induce this model neonatal C57BL/6J male mice were exposed to low-dose streptozotocin and were fed a high-fat diet (HFD) from the age of 4weeks to 14weeks. Curcumin was given at 100mg/kg dose daily by oral gavage started at the age of 10weeks and continued until 14weeks along with HFD feeding. We found that curcumin improved the histopathological changes of the NASH liver via reducing the level of steatosis, fibrosis associated with decreasing serum aminotransferases. In addition, curcumin treatment markedly reduced the hepatic protein expression of oxidative stress, pro-inflammatory cytokines, and chemokines including interferon (IFN) γ, interleukin-1ß and IFNγ-inducible protein 10, in NASH mice. Furthermore, curcumin treatment significantly reduced the cytoplasmic translocation of high mobility group box 1 (HMGB1) and the protein expression of toll like receptor 4. Nuclear translocation of nuclear factor kappa B (NF-κB) was also dramatically attenuated by the curcumin in NASH liver. Curcumin treatment effectively reduced the progression of NASH to HCC by suppressing the protein expression of glypican-3, vascular endothelial growth factor, and prothrombin in the NASH liver. Our data suggest that curcumin reduces the progression of NASH and liver damage, which may act via inhibiting HMGB1-NF-κB translocation.

Time-dependent changes in the suppressive effect of electric field exposure on immobilization-induced plasma glucocorticoid increase in mice.

We recently reported that increased glucocorticoid (GC) levels in immobilized mice were suppressed by exposure to a 50-Hz electric field (EF) in kV/m-dependent and exposure duration-dependent manners. Here, we characterized time-dependent changes in the effect of EF exposure in immobilized mice. Using control, EF-alone, immobilization-alone, and co-treated groups, plasma GC levels, and blood properties were first measured (0-60 min) to observe changes induced by each treatment and measured again (60-120 min) to assess recovery from each treatment. The 50-Hz, 10-kV/m EF was formed in a parallel plate electrode. Co-treated mice were exposed to the EF for 60 min for the first measurement and were immobilized for the second half (30-60 min) of the EF exposure period. Plasma GC levels did not change significantly over time in the control and EF-alone groups. GC levels in the immobilization-alone and co-treated groups increased after immobilization, peaking 30 min after the start of immobilization and then decreasing gradually; however, the GC peak was lower in the co-treated group than in the immobilization-alone group (P < 0.05 at 50 and P < 0.001 at 60 min). Red blood cell counts, hemoglobin levels, and hematocrit values increased after immobilization but were not affected by the EF. Our findings indicate that the EF did not shift the peak of the time-dependent increase in plasma GC levels in immobilized mice but simply reduced it. Bioelectromagnetics. 38:272-279, 2017. © 2017 Wiley Periodicals, Inc.

The efficacy of a multidisciplinary team approach in critical limb ischemia.

The aim of the present study was to clarify the characteristics of Japanese critical limb ischemia (CLI) patients and analyze the rates of real-world mortality and amputation-free survival (AFS) in all patients with Fontaine stage IV CLI who were treated with/without revascularization therapy by an intra-hospital multidisciplinary care team. All consecutive patients who presented with CLI at Showa University Fujigaoka Hospital between April 2008 and March 2014 were prospectively registered. The intra-hospital committee consisted of cardiologists, plastic surgeons, dermatologists, diabetologists, nephrologists, cardiovascular surgeons, and vascular technologists. The primary endpoint of this study was all-cause mortality and AFS during the follow-up period. The present study included 145 patients with Fontaine stage IV CLI. The mean age was 76.5 ± 10.2 years. The all-cause mortality rate during the follow-up period (15.5 ± 16.1 months) was 21.4 %. The AFS rate during the follow-up period (14.1 ± 16.4 months) was 58.6 %. A multivariate Cox proportional hazards regression analysis found that age >75 years and hemodialysis were significantly associated with all-cause mortality; and that age >75 years, Rutherford 6, and wound infection were significantly associated with AFS. A multidisciplinary approach and comprehensive care may improve the outcomes and optimize the collaborative treatment of CLI patients. However, all-cause mortality remained high in patients with Fontaine stage IV CLI and early referral to a hospital that can provide specialized treatment for CLI, before the occurrence of major tissue loss or infection, is necessary to avoid primary amputation.

Probucol dramatically enhances dihydroartemisinin effect in murine malaria.

BACKGROUND: Artemisinin-based combination therapy (ACT) has been adopted as national policy for the first-line treatment in large number of malaria-endemic regions. However, artemisinin-resistant parasites have emerged and are spreading, with slow-cleaning parasites being reported in patients treated with ACT. It means that more parasites are exposed to the partner drug alone and the risk of developing resistant parasites against the partner drug is increasing. Therefore, the development of a new method to enhance the effect of artemisinin is required. In this study, the potential effect of probucol as a combination drug of dihydroartemisinin (DHA), an artemisinin derivative, was examined. METHODS: C57BL/6 J mice infected with Plasmodium yoelii XL-17 were treated with probucol and/or DHA. The mice were fed with a probucol mixed diet from 2 weeks before infection and through infection period. DHA was injected to mice three to 5 days post infection once a day. In addition, 0.5 % (w/w) probucol was mixed with vitamin E supplemented diet (800 mg/kg) and fed to mice infected with P. yoelii XL-17 to examine the mechanisms of probucol on murine malaria. Furthermore, 8-OHdG, a biomarker of oxidized DNA, was detected in infected red blood cells (iRBC) taken from infected mice by immunofluorescent staining. RESULTS: With dose-dependent manner, both probucol and DHA decreased parasitaemia and increased survival rate of mice infected with P. yoelii XL-17. A significantly larger amount of 8-OHdG was detected in iRBC taking from probucol-treated mice than control mice. In addition, a large amount of vitamin E supplementation eliminated the effect of probucol against P. yoelii XL-17 infection and lowered the effect of probucol on host plasma vitamin E concentration. The effective doses for probucol and DHA were 0.5 % and 30 mg/kg, respectively, in each single treatment. While the combination treatment of 0.25 % probucol and 7.5 mg/kg DHA was effective in all mice from P. yoelii XL-17 infection. CONCLUSION: This study demonstrated that probucol has some impact on malaria by oxidative stress through the induction of host plasma vitamin E deficiency. Moreover, the effective dose of DHA on malaria was decreased by prophylactic treatment of probucol. This finding indicates that probucol might be a candidate for a prophylactic treatment drug to enhance the effect of DHA.

Hypothalamic glucagon signaling in fasting hypoglycemia.

AIMS: Sustained glucagon infusion increases hepatic glucose production, but this effect is transient due to hypothalamic glucagon signaling. In hypoglycemia, glucagon acts as a major defense to sustain the blood glucose level and this raises the question regarding glucagon signaling associated glucose production in prolonged fasting hypoglycemia. In this study, we investigated the proteins associated with hypothalamic glucagon signaling and liver gluconeogenesis during fasting hypoglycemia. MAIN METHODS: 8-9week old, male C57BL6/J mice were fasted for 4, 8, 12, 18, 24, 30, 36 or 42h. In the hypothalamus, we investigated glucagon signaling by analyzing the glucagon receptor and its downstream protein, peroxisome proliferator-activated receptor-gamma coactivator 1 (PGC-1) expression. In the liver, we investigated gluconeogenesis by analyzing p-protein kinase A (PKA)(Ser/Thr) substrate and phosphoenolpyruvate carboxykinase - cytosolic (PEPCK-C) expression using the western blotting technique. KEY FINDINGS: The elevated or trended higher hypothalamic glucagon receptor and PGC-1 expressions at 18 and 42h were correlated with the attenuated liver p-PKA(Ser/Thr) substrate expression. The attenuated hypothalamic glucagon receptor and PGC-1 expressions at 12, 24, 30 and 36h were correlated with the elevated or trended higher liver p-PKA(Ser/Thr) substrate expression. SIGNIFICANCE: The hypothalamic glucagon signaling during fasting hypoglycemia might have been modulated by circadian rhythm and this possibly attenuates the liver p-PKA(Ser/Thr) substrate to modify the gluconeogenesis pathway. This mechanism will help to understand the hyperglucagonemia associated complications in diabetes.

Attenuation of Endoplasmic Reticulum Stress-Mediated Liver Damage by Mulberry Leaf Diet in Streptozotocin-Induced Diabetic Rats.

Endoplasmic reticulum stress (ERS) plays a crucial role in the development of insulin resistance and diabetes mellitus. Although antidiabetic use of mulberry leaves (MLs) has been popular due to their many anti-oxidative flavonoid compounds and free radical scavenging effects, ML's effects on ERS in experimental diabetic hepatocyte injury remain unknown. To investigate how ML affect ERS in diabetic liver, Sprague-Dawley (SD) rats were assigned to induce diabetes by a single intraperitoneal injection of streptozocin (STZ; 55 mg/kg) and fed with either normal chow or a diet containing 25% mulberry leaf powder diet (MLD) and examined for 56 days. We observed that MLD improved the rats' morphological and histopathological changes. Levels of ERS markers such as phosphorylated double-stranded RNA-dependent protein kinase-like endoplasmic reticulum kinase (PERK) and X-box binding protein 1 (XBP1) and the protein expression of glucose regulated protein 78 (GRP78) were significantly higher in the diabetic liver compared to normal liver. MLD for 8 weeks significantly reduced all of these markers. MLD also significantly decreased hepatocyte apoptosis, hepatic macrophage recruitment, cellular infiltration, and CCAAT/enhancer-binding protein homologous protein (CHOP), tumor necrosis factor receptor associated factor 2 (TRAF2), interleukin 1[Formula: see text] (IL-1[Formula: see text]) and sterol regulatory element binding protein isoform 1c (SREBP 1c) levels in diabetic liver. These results may suggest that MLs can preserve hepatic function in experimental diabetes by modulating ERS mediated apoptosis and liver damage.