Oral alkalinizing supplementation suppressed intrarenal reactive oxidative stress in mild-stage chronic kidney disease: a randomized cohort study.

BACKGROUND: The beneficial effects of oral supplements with alkalinizing agents in patients with chronic kidney disease (CKD) have been limited to the severe stages. We investigated whether two types of supplements, sodium bicarbonate (SB) and potassium citrate/sodium citrate (PCSC), could maintain renal function in patients with mild-stage CKD. METHODS: This was a single-center, open-labeled, randomized cohort trial. Study participants with CKD stages G2, G3a, and G3b were enrolled between March 2013 and January 2019 and randomly assigned by stratification according to age, sex, estimated glomerular filtration rate (eGFR), and diabetes. They were followed up for 6 months (short-term study) for the primary endpoints and extended to 2 years (long-term study) for the secondary endpoints. Supplementary doses were adjusted to achieve an early morning urinary pH of 6.8-7.2. We observed renal dysfunction or new-onset cerebrovascular disease and evaluated urinary surrogate markers for renal injury. RESULTS: Overall, 101 participants were registered and allocated to three groups: standard (n = 32), SB (n = 34), and PCSC (n = 35). Two patients in the standard group attained the primary endpoints (renal stones and overt proteinuria) but were not statistically significant. There was one patient in the standard reduced eGFR during the long-term study (p = 0.042 by ANOVA). SB increased proteinuria (p = 0.0139, baseline vs. 6 months), whereas PCSC significantly reduced proteinuria (p = 0.0061, baseline vs. 1 year, or p = 0.0186, vs. 2 years) and urinary excretion of 8-hydroxy-2'-deoxyguanosine (p = 0.0481, baseline vs. 6 months). CONCLUSION: This study is the first to report supplementation of PCSC reduced intrarenal oxidative stress in patients with mild-stage CKD.

Reno-protective effects of oral alkalizing agents in chronic kidney disease with aciduria: protocol for a randomized cohort study.

BACKGROUND: Aciduria caused by urinary excretion of acidic metabolic wastes produced in daily life is known to be augmented in patients with chronic kidney disease (CKD). To evaluate the reno-protective effect of oral alkalizing agents for the improvement of metabolic acidosis and neutralization of intratubular pH in the patients with mild stages of CKD. Also, to identify reno-protective surrogate markers in the serum and urine that can closely associate the effect of urine alkalization. METHODS: In this single-centered, open-labeled, randomized cohort study, patients with CKD stages G2, G3a and G3b, who visited and were treated at Tohoku University Hospital during the enrollment period were registered. We administered sodium bicarbonate or sodium-potassium citrate as the oral alkalinizing agents. A total of 150 patients with CKD will be randomly allocated into the following three groups: sodium bicarbonate, sodium-potassium citrate and standard therapy group without any alkalinizing agents. The data of performance status, venous blood test, spot urine test, venous blood-gas test, electrocardiogram, renal arterial ultrasonography and chest X-ray will be collected at 0, 6, 12 and 24 weeks (short-term study) from starting the interventions. These data will be also collected at 1 and 2 years (long-term study). The samples of plasma and serum and early-morning urine at every visit will be acquired for the analysis of renal function and surrogate uremic biomarkers. The recruitment for this cohort study terminated in March, 2018, and the follow-up period for all the enrolled subjects will be terminated in December, 2020. The primary endpoint will be the development of originally-defined significant renal dysfunction or the occurrence of any cerebrovascular disease in the short-term study. The secondary endpoint will be the same endpoints as in the long-term study, or the patients with significant changes in the suggested the surrogate biomarkers. DISCUSSION: The findings of this study will address the importance of taking oral alkalizing agents in the patients with early stages of CKD, furthermore they could address any new surrogate biomarkers that can be useful from early stage CKD. TRIAL REGISTRATION: Registered Report Identifier: UMIN000010059 and jRCT021180043. The trial registration number; 150. Date of registration; 2013/02/26.

Synthesis of a novel human PPARδ selective agonist and its stimulatory effect on oligodendrocyte differentiation.

We successfully synthesized a novel peroxisome proliferator-activated receptor (PPAR)δ selective agonist, namely, compound 20, with a characteristic benzisoxazole ring. Compound 20 exhibited potent human PPARδ transactivation activity and high δ selectivity. Further, it stimulated differentiation of primary oligodendrocyte precursor cells in vitro, indicating that it may be an effective drug in the treatment of demyelinating disorders such as multiple sclerosis.

Biological evaluation of novel benzisoxazole derivatives as PPARδ agonists.

We discovered novel peroxisome proliferator-activated receptor δ agonists with a characteristic benzisoxazole ring. Compound 5 exhibited potent human PPARδ transactivation activity. Furthermore, it stimulated the differentiation of oligodendrocyte precursor cells in vitro. This indicates that this potential drug may be effective for the treatment of demyelinating disorders such as multiple sclerosis.

Modulation of the stress response by coffee: an in vivo microdialysis study of hippocampal serotonin and dopamine levels in rat.

We studied whether coffee and its components (caffeine and chlorogenic acid) have stress-relaxing effects. In vivo brain microdialysis was used to characterize the effects of coffee, stress, and their interaction on the serotonergic and dopaminergic systems in the rat hippocampus. Restraint stress for 100 min caused a marked increase in dopamine and serotonin (5-HT) levels in the hippocampus, and then, 100 min resting (freely-moving) time reduced them to basal levels. Pretreatment with 33 mg/kg coffee or 1.7 mg/kg caffeine reduced the second restraint-induced increase in the neurotransmitters, especially 5-HT, but neither saline nor 1.7 mg/kg chlorogenic acid did. These results suggest that coffee contributes to the reduction of restraint-induced stress and that these effects could be due to caffeine. Possible mechanisms of the effects are considered.