Development of sandwich enzyme-linked immunosorbent assays quantifying mouse urinary megalin, a novel proximal tubular biomarker.

Megalin, a type I transmembrane protein, serves as a multi-ligand endocytic receptor in the apical membrane of proximal tubules. Its ectodomain and full-length forms are excreted into human urine, with the former being more abundant. We previously developed two types of sandwich enzyme-linked immunosorbent assays (ELISAs) utilizing monoclonal antibodies that target the amino-terminal ligand-binding domain-I and the carboxyl-terminal cytoplasmic region of human megalin, respectively. The former, termed "A-megalin" ELISA, primarily identifies ectodomains of megalin, whereas the latter, "C-megalin" ELISA, specifically recognizes full-length megalin originating from urinary extracellular vesicles. This study developed novel sandwich ELISAs to assess mouse urinary A-megalin and C-megalin, thereby facilitating studies involving these biomarkers in mouse disease models. Immunoblotting and immunohistochemistry of monoclonal antibodies against human megalin were performed to assess their compatibility with mouse megalin in novel sandwich ELISAs, which were constructed and validated using human assay protocols. Immunoblot analysis of megalin in urinary extracellular vesicles and supernatant was performed to investigate the ratio of ectodomain to full-length forms in mouse urine. Stable measurements having a precision and accuracy within 15 % were achieved in the measurement of quality control samples. A-megalin and C-megalin were detectable in the urine of C57BL/6 mice, whereas most urine samples from kidney-specific conditional megalin-knockout mice were below detection limits. Ectodomain forms of megalin were at least approximately 70 times more abundant than the full-length form, even in mouse urine. In conclusion, we successfully developed sandwich ELISAs for assessing mouse urinary A-megalin and C-megalin to evaluate primarily ectodomain and full-length forms of megalin, respectively.

Survival and cognitive deterioration in elderly patients undergoing hemodialysis.

AIM: This study aimed to elucidate the 5-year changes in the cognitive function of elderly patients undergoing hemodialysis and its association with survival and related factors. METHODS: Cognitive function in patients aged ≥65 years undergoing hemodialysis at the Nagasaki Renal Center was assessed using the Mini-Mental State Examination (MMSE) in 2016. Patients were subsequently classified into normal, mild cognitive impairment (MCI) and suspected dementia groups according to their scores; MMSE was conducted at 30 and 60 months thereafter. The patients were followed until 2021. The association between survival and patient backgrounds was analyzed. RESULTS: Of the 181 patients, 168 completed follow-up and were classified into normal (n = 71, 42.3%), MCI (n = 44, 26.1%), and suspected dementia (n = 53, 31.5%) groups. Multivariable logistic regression analysis showed that age, female sex, and geriatric nutritional risk index were associated with MMSE scores <24. The 5-year survival rates were 60.6%, 40.9%, and 22.6% in the normal, MCI and suspected dementia groups, respectively. With some exceptions, MMSE results tended to decline during the observation period. A multivariate Cox proportional hazards model showed that age (hazard ratio [HR], 1.04; P = 0.007), dialysis vintage (HR, 0.96; P = 0.04), male sex (HR, 1.77; P = 0.02), geriatric nutritional risk index (HR, 0.94; P < 0.001) and MMSE score (HR, 0.96; P = 0.01) were independent risk factors for patient survival. CONCLUSIONS: Cognitive impairment in patients undergoing hemodialysis was associated with age and nutritional status. Patients with cognitive impairment had a poor prognosis. Geriatr Gerontol Int 2023; 23: 111-116.

A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Phase 2b Trial of P2X3 Receptor Antagonist Sivopixant for Refractory or Unexplained Chronic Cough.

INTRODUCTION: To determine the optimal dose of sivopixant, a highly selective P2X3 receptor antagonist, for refractory or unexplained chronic cough (RCC/UCC). METHODS: In this phase 2b, randomized, double-blind, placebo-controlled, parallel-group, multicenter trial, patients received sivopixant 50, 150, or 300 mg or placebo once daily for 4 weeks. The primary endpoint was a change from baseline in 24-h cough frequency (coughs/h) with sivopixant vs placebo. RESULTS: Overall, 390/406 randomized patients completed the study. Placebo-adjusted changes in hourly cough count over 24 h were 13.17% (P = 0.3532), - 1.77% (P = 0.8935), and - 12.47% (P = 0.3241) and in cough severity (visual analog scale) were 1.75 mm (P = 0.5854), - 1.21 mm (P = 0.7056), and - 6.55 mm (P = 0.0433) with sivopixant 50, 150, and 300 mg, respectively. Placebo-adjusted changes from baseline in Leicester Cough Questionnaire total scores were - 0.37 (P = 0.4207), - 0.07 (P = 0.8806), and 0.69 (P = 0.1473) with sivopixant 50, 150, and 300 mg, respectively. Additionally, 61.3%, 78.3%, 86.8%, and 71.4% of patients receiving sivopixant 50, 150, and 300 mg and placebo, respectively, reported any improvements in Patient Global Impression of Change. The incidence of treatment-emergent adverse events (TEAEs) was 25.7%, 32.0%, 49.0%, and 20.6% in sivopixant 50, 150, and 300 mg and placebo groups, respectively; all TEAEs in the sivopixant group were mild-to-moderate. CONCLUSION: Sivopixant did not demonstrate a statistically significant difference vs placebo in change from baseline in 24-h cough frequency. The dose of 300 mg has potential for RCC/UCC, showing the greatest improvements in cough frequency and patient-reported outcomes and dose-related mild to moderate reversible taste disturbance, although further trials are needed. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT04110054; registered September 26, 2019.

Randomised trial of the P2X3 receptor antagonist sivopixant for refractory chronic cough.

BACKGROUND: The purinoceptor subtype P2X3 has been shown to have significant involvement in the cough reflex; the heterotrimer version of the purinoceptor (P2X2/3) has been implicated in taste disturbance. The most advanced clinical candidate antagonist gefapixant has low selectivity among P2X3 receptors and induced taste disturbance, whereas newly developed sivopixant has high selectivity towards P2X3 versus P2X2/3. METHODS: In a phase 2a, randomised, double-blind, placebo-controlled, crossover, multicentre study, adult patients with refractory or unexplained chronic cough received oral sivopixant 150 mg or placebo once daily for 2 weeks, followed by a 2-3-week washout period, and then crossed over to placebo or sivopixant for 2 weeks. Efficacy and safety of sivopixant were evaluated. RESULTS: Of 31 randomised patients, 15 in the sivopixant-first group and 15 in the placebo-first group completed the study. After 2 weeks of treatment, the placebo-adjusted ratios of the average hourly number of coughs to baseline during daytime (primary end-point) and over 24 h (secondary end-point) were -31.6% (p=0.0546) and -30.9% (p=0.0386), respectively. Sivopixant also improved health-related quality of life. Treatment-related adverse events occurred in 12.9% and 3.2% of patients during sivopixant and placebo administration, respectively. Mild taste disturbance occurred in two patients (6.5%) during sivopixant administration. CONCLUSIONS: Sivopixant reduced objective cough frequency and improved health-related quality of life, with a low incidence of taste disturbance, among patients with refractory or unexplained chronic cough.

[Possible relationship between prescription medications and urinary dysfunction in elderly home health care patients].

AIM: Although urinary incontinence (UI) in the elderly appears to be related to polypharmacy, it is unclear whether multiple medications elevate UI quantitatively or qualitatively. There have been few studies on the association of polypharmacy with each type of UI. The present survey aimed to clarify these issues. METHOD: The subjects were elderly home health care patients ≥65 years of age taking ≥5 prescription medications and not being treated with anti-cancer agent. The visiting nurses filled out a questionnaire based on their nursing and medication records. Types of UI were evaluated according to a UI checklist. RESULTS: A total of 167 subjects (97 women, 70 men, mean age of 83.8 years) were eligible for the data analysis. Subjects talking 5-9 prescription medications accounted for 59.3%, while those talking≥10 counted for 40.7%. Men talking ≥10 medications showed a slight but non-significant increased risk of UI. In women, α-adrenergic antagonists and benzodiazepines significantly increased the risk of stress UI and urge UI, respectively. Furthermore, α-adrenergic antagonists reduced the risk of functional UI, whereas acetylcholinesterase inhibitors elevated it. α-adrenergic antagonists in combination with benzodiazepines also significantly increased the risk of stress UI and urge UI, while α-adrenergic antagonists with acetylcholinesterase inhibitors increased the risk of stress UI. In men, there were no prescription medications that were particularly related to UI. CONCLUSIONS: The present results suggest that there are gender differences in prescription medications-induced UI. It is likely that the causing medications are different depending on the type of UI, and the combination of them significantly increase the risk of UI.

Clinical Effects of Formulated Food of Peucedanum japonicum Extract and Saw Palmetto Extract in Male Patients with Lower Urinary Tract Symptoms.

OBJECTIVES: To evaluate changes over time in subjective symptom scores and urination parameters before and after oral administration of formulated food containing a combination of Peucedanum japonicum (P. japonicum) extract and saw palmetto extract (SPE) in male patients with lower urinary tract symptoms (LUTS). METHODS: This study was conducted in an open label manner on male patients with untreated LUTS. The urination state of patients was evaluated before and after administration of food formulated with P. japonicum extract and SPE for 4 weeks, based on urodynamic parameters and subjective symptom scores (International Prostate Symptom Score [IPSS and IPSS-QOL], Overactive Bladder Symptom Score [OABSS], Overactive Bladder Questionnaire [OAB-q], and International Index of Erectile Function [IIEF]). RESULTS: After the administration of food formulated with these extracts, the following results were obtained: (i) Subjective findings: The IPSS-QOL score improved significantly; both parameters related to nocturia, i.e., frequency of nighttime urination and OABSS-2, improved significantly; other ratings for subjective symptoms slightly improved. (ii) Objective findings: Residual urine volume decreased significantly, and blood prostate specific antigen (PSA) and urinary 8-OHdG levels decreased slightly after the treatment. (iii) Other findings: Blood pressure decreased slightly. No adverse drug reactions were reported. (iv) Patient impressions: 75% of patients gave a rating of "Good" or higher, with 15 out of 20 patients wanting to continue treatment after the end of 4-week administration period. CONCLUSIONS: Food formulated with P. japonicum extract and SPE may be useful to decrease frequency of nighttime urination and residual urine volume in male patients with LUTS.

Ganglioside GD3 enhances adhesion signals and augments malignant properties of melanoma cells by recruiting integrins to glycolipid-enriched microdomains.

Ganglioside GD3 is widely expressed in human malignant melanoma cell lines and tumors. Previously, we reported that GD3+ cells show stronger tyrosine phosphorylation of focal adhesion kinase (FAK), p130(Cas), and paxillin when treated with fetal calf serum than GD3- cells. In this study, we analyzed the changes in the signals mediated by the interaction between integrins and extracellular matrices (ECM) to clarify how GD3 enhances cell signals in the vicinity of the cell membrane. An adhesion assay with a real time cell electronic sensing system revealed that GD3+ cells had stronger adhesion to all extracellular matrices examined. In particular, GD3+ cells attached more strongly to collagen type I and type IV than controls. Correspondingly, they showed stronger tyrosine phosphorylation of FAK and paxillin during adhesion to collagen type I. In the floating pattern of detergent extracts, a high level of integrin beta1 was found in glycolipid-enriched microdomain (GEM)/rafts in GD3+ cells before adhesion, whereas a smaller amount of integrin beta1 was detected in the GEM/rafts of controls. Some phosphorylated forms of FAK as well as total FAK were found in GEM/rafts during cell adhesion only in GD3+ cells. Another signal consisting of integrin-linked kinase/Akt was also activated during adhesion more strongly in GD3+ cells than in controls. In double stained GD3+ cells, GD3 and integrin beta1 co-localized at the focal adhesion with a punctate pattern. All these results suggested that integrins assembled and formed a cluster in GEM/rafts, leading to the enhanced signaling and malignant properties under GD3 expression.

Essential roles of integrin-mediated signaling for the enhancement of malignant properties of melanomas based on the expression of GD3.

We reported that ganglioside GD3 enhances cell proliferation and invasion of melanomas causing stronger tyrosine-phosphorylation of p130Cas and paxillin after stimulation with fetal calf serum. Besides signals via growth factor/receptor, adhesion signals via integrin might be also enhanced by GD3. Here, roles of integrin-mediated signaling in the cell proliferation and invasion, and in the activation of adaptor molecules were examined, showing that integrin was also important for the cell growth and invasion. p130Cas and paxillin underwent stronger tyrosine-phosphorylation in GD3+ cells than in GD3- cells during the adhesion in the absence of serum. On the other hand, no proteins underwent tyrosine phosphorylation in GD3+ and GD3- cells in a suspension state when stimulated with fetal calf serum. These results suggested that integrin-mediated signaling is essential in the effects of GD3 on the malignant properties of melanomas. Co-localization of GD3 and integrin at the focal adhesion supported these results.

Focal adhesion kinase as well as p130Cas and paxillin is crucially involved in the enhanced malignant properties under expression of ganglioside GD3 in melanoma cells.

Mass spectrometry analysis of immunoprecipitates from serum-treated GD3-expressing melanoma cells with PY20 (anti-phosphotyrosine antibody) revealed that focal adhesion kinase (FAK) is more strongly activated in GD3-expressing cells than in GD3-negative cells. Involvement of FAK in the increased proliferation and invasion in GD3-expressing melanomas was demonstrated by siRNA-mediated knockdown. Also, it was shown that FAK is located up-stream of p130Cas and paxillin in the enhanced signaling pathway. GD3 expression enhanced the association of FAK with p130Cas after treatment with fetal calf serum. Thus, focal adhesion kinase as well as p130Cas and paxillin should be a crucial molecule undergoing stronger tyrosine phosphorylation in GD3-expressing melanoma cells. Molecules linking GD3 and FAK such as integrins in the enhanced signaling pathway remain to be investigated.