Construction of a screening system for lipid-derived radical inhibitors and validation of hit compounds to target retinal and cerebrovascular diseases.

Recent studies have highlighted the indispensable role of oxidized lipids in inflammatory responses, cell death, and disease pathogenesis. Consequently, inhibitors targeting oxidized lipids, particularly lipid-derived radicals critical in lipid peroxidation, which are known as radical-trapping antioxidants (RTAs), have been actively pursued. We focused our investigation on nitroxide compounds that have rapid second-order reaction rate constants for reaction with lipid-derived radicals. A novel screening system was developed by employing competitive reactions between library compounds and a newly developed profluorescence nitroxide probe with lipid-derived radicals to identify RTA compounds. A PubMed search of the top hit compounds revealed their wide application as repositioned drugs. Notably, the inhibitory efficacy of methyldopa, selected from these compounds, against retinal damage and bilateral common carotid artery stenosis was confirmed in animal models. These findings underscore the efficacy of our screening system and suggest that it is an effective approach for the discovery of RTA compounds.

The Early Pathogenesis of Diabetic Retinopathy and Its Attenuation by Sodium-Glucose Transporter 2 Inhibitors.

The early pathogenetic mechanism of diabetic retinopathy (DR) and its treatment remain unclear. Therefore, we investigated the early pathogenic alterations in DR using streptozotocin-induced diabetic mice and the protective effect of sodium-glucose cotransporter 2 (SGLT2) inhibitors against these alterations. Retinal vascular leakage was assessed by dextran fluorescence angiography. Retinal thickness and vascular leakage were increased 2 and 4 weeks after onset of diabetes, respectively. Immunostaining showed that morphological change of microglia (amoeboid form) was observed at 2 weeks. Subsequently, increased angiopoietin-2 expression, simultaneous loss of pericytes and endothelial cells, decreased vessel density, retinal hypoxia, and increased vascular endothelial growth factor (VEGF)-A/VEGF receptor system occurred at 4 weeks. SGLT2 inhibitors (luseogliflozin and ipragliflozin) had a significant protective effect on retinal vascular leakage and retinal thickness at a low dose that did not show glucose-lowering effects. Furthermore, both inhibitors at this dose attenuated microglia morphological changes and these early pathogenic alterations in DR. In vitro study, both inhibitors attenuated the lipopolysaccharide-induced activation of primary microglia, along with morphological changes toward an inactive form, suggesting the direct inhibitory effect of SGLT2 inhibitors on microglia. In summary, SGLT2i may directly prevent early pathogenic mechanisms, thereby potentially playing a role in preventing DR.

Imaging analysis for multiple paramagnetic agents using OMRI and electrophoresis.

Nitroxides have been widely used as a molecular probe for analysis of various diseases models. This article describes an analytical method for separation and semi-quantification of multiple paramagnetic contrast agents with simple procedure combining electrophoresis and Overhauser enhancement magnetic resonance imaging (OMRI) imaging. We used three nitroxides, 3-carbamoyl PROXYL, 3-carboxy PROXYL, and CAT-1, which have different ionic charges in the molecule. In addition, we showed that this method could apply for in vitro measurement using biological sample. The results showed the nitroxides were successfully separated with electrophoresis depending on their charge, and their separation was visualized with OMRI after electrophoresis. Vehicle media such as whole blood did not affect the electrophoresis results and OMRI enhancement factor. Thus, the method can be used to analyze the redox status of biological samples without preprocessing. This analytical method enables in vitro measurement of biological samples to determine the redox status of specific tissue layers using paramagnetic agents, which is helpful for detailed analysis of redox-related diseases.

Low dose of sodium-glucose transporter 2 inhibitor ipragliflozin attenuated renal dysfunction and interstitial fibrosis in adenine-induced chronic kidney disease in mice without diabetes.

BACKGROUND: Sodium-glucose co-transporter 2 (SGLT2) inhibitor, a new class of glucose lowering agents, has been shown to be reno-protective in diabetes. OBJECTIVE: We aimed to explore whether SGLT2 inhibitor ipragliflozin has a direct reno-protective effect on non-diabetic chronic kidney disease (CKD) in mice. METHODS: CKD mice was induced by feeding of 0.25% w/w adenine containing diet. Low dose ipragliflozin (0.03 or 0.1 mg/kg/day) was orally administered to CKD mice for 4 weeks, concomitantly with adenine containing diet. RESULTS: CKD mice exhibited increases in kidney weight/body weight ratio, plasma creatinine levels, urinary fatty acid binding protein 1 excretion and plasma interleukin-6 levels, and a decrease in hematocrit, accompanied by morphological changes such as crystal deposits in the tubules, tubular dilatation, interstitial fibrosis, and increased 8-hydroxy-2'-deoxyguanosine staining. Low dose ipragliflozin (0.03 or 0.1 mg/kg/day) did not affect either plasma glucose levels or urinary glucose excretion, while it improved levels in plasma creatinine (P < 0.05 for 0.03 mg/kg/day, P < 0.001 for 0.1 mg/kg/day), interleukin-6 (P < 0.05 for 0.1 mg/kg/day) and hematocrit (P < 0.05 for 0.1 mg/kg/day), and morphological changes dose-dependently except crystal deposit formation in the CKD mice. CONCLUSIONS: Low-dose ipragliflozin has a reno-protective effect in non-diabetic adenine-induced CKD mice, independently of plasma glucose levels and urinary glucose excretion. Low dose SGLT2 inhibitor may be a useful therapeutic option for non-diabetic CKD with the advantage of fewer adverse effects.

Electrochemical Reactions of Iodine Molecules Encapsulated in Single-Walled Carbon Nanotubes.

We prepared iodine molecules encapsulated in single-walled carbon nanotubes (I@SWCNTs) by electro-oxidation of iodide ions with empty SWCNT electrode. Li-ion battery electrode properties of I@SWCNTs were investigated. It was found that the I@SWCNT sample can catch and release Li ions reversibly. We performed Raman measurements to reveal the Li-ion storage mechanism of I@SWCNT. It is plausible that chemical reactions of I2 from/into LiI in SWCNTs occur during Li-ion charging/discharging of I@SWCNT. We also prepared the CsI@SWCNT sample to verify that alkali metal ions can be extracted from alkali metal halide in SWCNTs. The extraction of cesium ions from CsI@SWCNT was confirmed by Raman measurements. It was also found that I@SWCNT can work as a Li-ion battery electrode in solid electrolyte as well.

Effect of molecular weight of hypromellose on mucin diffusion and oral absorption behavior of fenofibrate nanocrystal.

We investigated the effect of variation in the molecular weight of hypromellose (HPMC) on the oral absorption of fenofibrate (FFB) nanocrystal. Four types of HPMC with different molecular weights and sodium dodecyl sulfate (SDS) were used as dispersion stabilizers for FFB nanocrystal suspension. Wet-milling of FFB crystal with HPMC and SDS formed diamond-shaped FFB nanocrystals with approximately 150 nm diameter. HPMC was strongly adsorbed onto the FFB nanocrystal interface, and the amount of HPMC adsorbed was not dependent on the molecular weight of HPMC. However, the decrease in the molecular weight of adsorbed HPMC led to an improvement in the permeability of FFB nanocrystal through the mucin layer. The decrease in molecular weight of HPMC enhanced the flexibility of FFB nanocrystal interface and effectively inhibited its interaction with mucin. This led to faster diffusion of FFB nanocrystal through mucin. In vivo oral absorption studies showed rapid FFB absorption from FFB nanocrystal formulations using HPMC of low molecular weights. The present study revealed that the molecular weight of the dispersion stabilizer for drug nanocrystal formulation should be taken into consideration to achieve improved absorption of poorly water-soluble drugs after oral administration.

Upregulation of Fibroblast Growth Factors Caused by Heart and Neural Crest Derivatives Expressed 2 Suppression in Endometriotic Cells: A Possible Therapeutic Target in Endometriosis.

Several features exist that distinguish endometriotic cells from eutopic endometrial cells. Progesterone resistance is one of the main distinguishing features, although how progesterone resistance affects the phenotype of endometriotic cells is not fully elucidated. Heart and neural crest derivatives expressed 2 (HAND2) is a transcriptional factor that plays an important role in maintaining endometrial function in a progesterone-dependent manner. Therefore, we explored whether progesterone-dependent HAND2 is implicated in the progression of endometriosis. HAND2 was less expressed by endometriotic tissues compared to endometrial tissues. Suppression of HAND2 expression induced fibroblast growth factor 1 (FGF1), FGF2, and FGF9 in endometriotic stromal cells and consequently enhanced migration and invasion capacity. AZD4547, a FGF receptor inhibitor, diminished the migration and invasion of endometriotic cells in vitro. In the murine model of endometriosis, AZD4547 showed suppressive effects on the development of endometriotic lesions at a relatively low concentration. In conclusion, we demonstrated that FGF1, FGF2, and FGF9 are downstream effectors of HAND2 in endometriotic cells. Since HAND2-dependent FGFs play roles in enhancing invasive capacity of endometriotic cells, our results suggest that FGF receptor inhibitors, such as AZD4547, can be promising therapeutic targets for endometriosis.

Protective effects of mangafodipir against chemotherapy-induced ovarian damage in mice.

BACKGROUND: Given the seriousness of chemotherapy-induced ovarian injury in female cancer patients, the preservation of fertility, including through the use of cryopreservation technology and pharmaceuticals, requires investigation. Previous studies have shown that damage to the ovaries is related to oxidative stress caused by anticancer drugs. Therefore, superoxide dismutase (SOD) may represent a key factor in the pharmacological protection of the ovaries. The aim of our study was to identify the effects of mangafodipir, a manganese chelate and SOD-mimetic, on suppression of apoptosis in granulosa cells and primordial follicle activation induced by anticancer drugs. METHODS: Cell viability assays using methyltrichlorosilane solutions and immunoblotting for cleaved caspase-3 were performed in in vitro experiments with the simultaneous addition of mangafodipir to human non-luteinized granulosa cell line (HGrC) cultures treated with hydrogen peroxide (H2O2), cisplatin, or paclitaxel. Count and morphological analyses of follicles at each developing stage in the ovaries and immunohistochemistry for cleaved caspase-3, Ki67 and 4-hydroxynonenal, a marker for oxidative stress, were also performed using mangafodipir-injected 6-week-old female ICR mice treated with cisplatin or paclitaxel. Further, mangafodipir was injected into 6-week-old female BALB/c mice inoculated with ES-2 to analyze whether mangafodipir inhibits the anti-tumor effects of cisplatin or paclitaxel treatment. RESULTS: Mangafodipir attenuated apoptosis induced by H2O2 and anticancer drugs in vitro. Mangafodipir also decreased the expression of 4-hydroxynonenal and reduced cisplatin- and paclitaxel-induced apoptosis in granulosa cells in vivo. In addition, mangafodipir inhibited the loss of primordial follicles. Tumor xenograft studies in mice showed that mangafodipir did not affect anticancer drug antitumor effects. CONCLUSIONS: Oxidative stress might be one of the mechanisms of cisplatin- and paclitaxel-induced the loss of primordial follicles. Mangafodipir can reduce cisplatin- and paclitaxel-induced apoptosis in granulosa cells and primordial follicle activation partially via its SOD activity. At the same time, mangafodipir might have other potential mechanisms to inhibit the activation of primordial follicles. Further, mangafodipir attenuated the ovarian damage caused by cisplatin and paclitaxel without affecting their antitumor activities. Mangafodipir, therefore, though its efficacy might be limited, may be a new option for the preservation of fertility during anticancer treatment.

Thyroid Autoantibodies do not Impair the Ovarian Reserve in Euthyroid Infertile Women: A Cross-Sectional Study.

Patients with primary ovarian insufficiency (POI) have a high prevalence of thyroid autoimmune disorders. However, the extent of the contribution of thyroid autoantibodies or elevated thyroid-stimulating hormone (TSH) levels to decreased ovarian reserve is unclear. Therefore, we evaluated the serum levels of anti-Müllerian hormone (AMH) and thyroid autoantibodies [antithyroperoxidase antibody (TPOAb), and antithyroglobulin antibody (TgAb)] in euthyroid infertile women. One hundred and fifty-three women with normal menstrual cycles were recruited for this retrospective study. Serum levels of AMH were compared between patients with positive and negative thyroid autoantibodies. The correlation between serum levels of AMH and each thyroid autoantibody was also evaluated. Participants were observed to be either TPOAb or TgAb positive (n=27), only TPOAb positive (n=8), only TgAb positive (n=7), TPOAb and TgAb positive (double positive; n=12), and TPOAb and TgAb negative (double negative; n=126). No significant differences were found in serum AMH levels between the TPOAb- or TgAb-positive women and the antibody-double negative women. Serum AMH levels did not show a significant correlation with the concentration of TgAb or TPOAb. On the other hand, serum AMH levels negatively correlated with TSH levels in patients who were either positive for TPOAb or TgAb. Thyroid autoantibodies are not likely to influence ovarian reserve in euthyroid women whose TSH levels fall within the normal range although elevated TSH levels may be involved in the decline of serum AMH levels.

Involvement of mesosalpinx in endometrioma is a possible risk factor for decrease of ovarian reserve after cystectomy: a retrospective cohort study.

BACKGROUND: Serum anti-Müllerian hormone (AMH) concentration has been used to assess ovarian reserve in patients with endometriosis, especially when endometrioma surgery is involved. Previously, we reported that decreased serum AMH levels after cystectomy for endometriomas can recover to preoperative levels in some cases. In this present study, we assessed the sequential changes in serum AMH levels before and after cystectomy in terms of the state of the mesosalpinx prior to surgery. METHODS: The retrospective cohort study recruited 53 patients from a series of prospective studies conducted from 2009 to 2015. All patients underwent laparoscopic cystectomy for endometriomas. If either mesosalpinx was involved in the endometrioma or adnexal adhesion before cystectomy, the case was defined as 'involved mesosalpinx' (n = 14). If both mesosalpinx remained anatomically correct, the case was classified as 'intact mesosalpinx' (n = 39). Blood samples were obtained from the patients 2 weeks before surgery, and at 1 month and 1 year after surgery to assess serum AMH levels. RESULTS: The serum AMH levels (the involved group vs. the intact group) were 1.92 vs. 0.98 (P = 0.552) preoperatively, 0.59 vs. 1.99 (P = 0.049) at 1 month postoperatively, and 0.48 vs. 2.37 ng/mL (P = 0.007) at 1 year postoperatively. The involved mesosalpinx group showed a further decrease in serum AMH levels at 1 year postoperatively, while serum AMH levels in the intact mesosalpinx group tended to recover. CONCLUSION: These results suggest that pre-existing mesosalpinx disturbance, in combination with adhesiolysis, may be involved in the medium- and long-term decrease in ovarian reserve after endometrioma surgery. A disturbance in ovarian blood supply via the mesosalpinx may underlie this. TRIAL REGISTRATION: UMIN-CTR UMIN000019369 . Retrospectively registered October 15, 2015.

Usefulness of the Ultrasensitive Anti-Müllerian Hormone Assay for Predicting True Ovarian Reserve.

Serum concentration of anti-Müllerian hormone (AMH) is a useful marker for ovarian reserve. Measurement of AMH in clinical practice has gained widespread use to predict parameters such as the ovarian response, menopause, and recovery after chemotherapy. However, undetectable AMH levels assayed by conventional enzyme-linked immunosorbent assay (ELISA) kits fail to predict depletion of follicles because of low sensitivity of the kits. We investigated whether a recently developed ultrasensitive ELISA kit, picoAMH, would be more effective at detecting very low AMH levels in association with menstrual status. We analyzed 68 women with undetectable serum AMH levels using an ELISA kit, AMH Gen II. The AMH concentration of the same samples was detected in 36 samples using picoAMH; 32 samples were within the standard range, and 4 samples were out of the standard range but still detectable. Thirty-two women whose AMH levels were undetectable using the picoAMH all showed amenorrhea. We also found a significant correlation between the classes of serum AMH levels (undetectable, detectable under the limit of quantification, and measurable within the assay range) and menstrual status. Five of the 6 amenorrheic women with detectable AMH eventually achieved follicle growth. The present study demonstrated that very low AMH levels detectable using picoAMH correspond well to current and future ovulation status. This suggests that serum AMH levels can be useful for the assessment of ovarian reserve and follow-up of women with a declined ovarian reserve.

Anti-Müllerian hormone levels after laparoscopic cystectomy for endometriomas as a possible predictor for pregnancy in infertility treatments.

We assessed the associations between preoperative and postoperative serum anti-Müllerian hormone (AMH) levels and parameters of endometriosis and endometriomas surgery with the success of infertility treatments after cystectomy. Seventeen out of 54 patients got pregnant during the infertility treatments. In these patients, the median interval from surgery to conception was 16.3 months. The serum AMH levels 1-year postoperatively were significantly higher in the pregnant group compared to the non-pregnant group (3.44 ± 1.78 versus 2.17 ± 2.24 ng/ml, p = 0.049). The median interval from surgery to recurrence was 34.4 months, and no significant differences were found in the serum AMH levels at any time point between the recurrence and non-recurrence groups. Serum AMH levels 1 year after laparoscopic cystectomy for endometriomas may predict the success of postoperative infertility treatments, but not a recurrence of endometriomas.

Anti-Müllerian hormone as a possible predictor of fecundability in subfertile women over 38 years: a retrospective cohort study.

Anti-Müllerian hormone (AMH) is a relatively novel method for examining the ovarian reserve that reflects female reproductive function. In the era in which the number of women delaying attempts to conceive has increased, a good predictor for long-term fecundability has been explored. We performed the retrospective cohort study to investigate whether initial serum AMH levels are useful for predicting long-term fertility during infertility treatments. We recruited 149 women in the retrospective cohort, and 52 women were gravid during the follow-up period. According to the multiple logistic analyses, only age was found to have a significant correlation with pregnancy success in all women. In women ≥38 years, significantly higher serum AMH levels were detected in the pregnant group (median = 2.83 ng/mL, range = 1.11-6.29 ng/mL) than the non-pregnant group (median = 1.22 ng/mL, range = 0-9.46 ng/mL; p = 0.015). None of the women with serum AMH levels <0.7 ng/mL were pregnant during treatment. AMH may be used to identify poor pregnancy prospects in women who are above 38 years.

Time-lapse observations to analyze the effects of assisted hatching.

PURPOSE: Assisted hatching (AH) is an artificial disruption of the zona pellucida with the aim of facilitating embryo implantation. We used time-lapse observations of mouse embryos to examine the effect of AH in mouse blastocysts. METHODS: AH techniques were performed with acid Tyrode's solution. We compared the rates of blastocyst formation and blastocyst attachment to Ishikawa cells between the control (n = 28) and the AH group (n = 24). To analyze the effects of AH, 8-cell mice embryos were cultured under time-lapse observations (every 15 min). The time required for hatching, the hatching rates, the frequency of contraction, and the contraction rates in the blastocysts were analyzed. RESULTS: There were no significant differences between the two groups in hatching rate or attachment rate. The times required for hatching were 286 ± 22 min in the AH group and 990 ± 437 min in the control group (P = 0.018). The contraction frequencies in blastocysts were 3.5 ± 0.7 times in the AH group and 7.5 ± 2.5 times in the control group (P = 0.020). CONCLUSIONS: From the time-lapse observations we found that the time required for hatching and the frequency of contraction in blastocysts were both reduced by AH, although blastocyst formation and attachment were not affected.