Despite significant recent progress in copper‐catalyzed enantioselective hydroamination chemistry, the synthesis of chiral N‐arylamines, which are frequently found in natural products and ...pharmaceuticals, has not been realized. Initial experiments with N‐arylhydroxylamine ester electrophiles were unsuccessful and, instead, their reduction in the presence of copper hydride (CuH) catalysts was observed. Herein, we report key modifications to our previously reported hydroamination methods that lead to broadly applicable conditions for the enantioselective net addition of secondary anilines across the double bond of styrenes, 1,1‐disubstituted olefins, and terminal alkenes. NMR studies suggest that suppression of the undesired reduction pathway is the basis for the dramatic improvements in yield under the reported method.
Winds of change: An efficient method for the preparation of enantioenriched N‐arylamines was developed by making key modifications to a previously reported hydroamination. The reaction is mediated by a copper(I)‐hydride (CuH) catalyst, and wide range of olefins and N‐arylhydroxylamines are compatible under the optimized conditions. Key to the successful development of this method was the addition of tBuOH and PPh3 to the reaction mixture.
A general, rapid, and efficient method for the copper‐catalyzed Finkelstein reaction of (hetero)aromatics has been developed using continuous flow to generate a variety of aryl iodides. The described ...method can tolerate a broad spectrum of functional groups, including N‐H and O‐H groups. Additionally, in lieu of isolation, the aryl iodide solutions were used in two distinct multistep continuous‐flow processes (amidation and Mg–I exchange/nucleophilic addition) to demonstrate the flexibility of this method.
Synthesis in flow: A flow system has been developed that enables a rapid halogen exchange in the copper‐catalyzed Finkelstein reaction of (hetero)aromatics. A broad scope of iodo compounds was prepared in good to excellent yields. Furthermore, two multistep continuous‐flow processes including either a halogen exchange/amidation or a halogen exchange/Mg–I exchange/nucleophilic addition sequence were established.
A highly regio- and enantioselective synthesis of 1,2-diamine derivatives from γ-substituted allylic pivalamides using copper-catalyzed hydroamination is reported. The N-pivaloyl group is essential, ...in both facilitating the hydrocupration step and suppressing an unproductive β-elimination from the alkylcopper intermediate. This approach enables an efficient construction of chiral differentially protected vicinal diamines under mild conditions with broad functional group tolerance.
Progranulin (PGRN) has been reported to bind tumor necrosis factor (TNF) receptor and to inhibit TNFα signaling. We evaluated the effect of augmentation of TNFα signaling by PGRN deficiency on the ...progression of kidney injury. Eight-week-old PGRN knockout (KO) and wild-type (WT) mice were fed a standard diet or high-fat diet (HFD) for 12 weeks. Albuminuria, markers of tubular damage, and renal mRNA levels of inflammatory cytokines were higher in HFD-fed KO (KO-HFD) mice than in HFD-fed WT (WT-HFD) mice. Body weight, vacuolization in proximal tubules, and systemic and adipose tissue inflammatory markers were lower in the KO-HFD mice than in the WT-HFD mice. The renal megalin expression was lower in the KO mice than in the WT mice regardless of the diet type. The megalin expression was also reduced in mouse proximal tubule epithelial cells stimulated with TNFα and in those with PGRN knockdown by small interfering RNA in vitro. PGRN deficiency was associated with both exacerbated renal inflammation and decreased systemic inflammation, including that in the adipose tissue of mice with HFD-induced obesity. Improved tubular vacuolization in the KO-HFD mice might partially be explained by the decreased expression of megalin in proximal tubules.
This study aimed to assess the suppressive effect of long-term diet supplementation with
strains on cognitive decline in the senescence-accelerated mouse prone 8 (SAMP8) model. For 43 weeks, ...fourteen-week-old female SAMP8 mice were fed a standard diet containing 0.05% (
/
)
subsp.
327 (L. 327) or
K71 (L. K71) derived from rice grains and sake lees, respectively. SAMP8 mice that were fed a L. K71-supplemented diet had better cognitive performance compared with the control and L. 327 groups in the Barnes maze and passive avoidance tests. An ELISA analysis revealed that the levels of serotonin were elevated in the serum and brain tissue of L. K71-fed mice. The protein expression levels of brain-derived neurotrophic factor (BDNF), cAMP response element binding protein (CREB), and phosphorylated CREB were evaluated using western blot. Long-term administration of L. K71 resulted in increased protein expression of BDNF and CREB phosphorylation in the hippocampus. These results suggest that prolonged intake of a diet supplemented with a
strain derived from sake lees may prevent age-dependent cognitive decline by upregulating BDNF expression in the hippocampus.
Aims/Introduction
Urinary kidney injury molecule‐1 (KIM‐1) has been associated with proximal tubular damage in human and animal studies. Although it has been recognized as a biomarker of acute kidney ...injury and chronic kidney disease, its significance in the serum remains unclear. Therefore, we examined the relationship of serum and urinary KIM‐1 levels with renal parameters in patients with type 2 diabetes.
Materials and Methods
Serum and urinary KIM‐1 levels, together with urinary liver‐type fatty acid‐binding protein, were measured in 602 patients with type 2 diabetes and an estimated glomerular filtration rate (eGFR) ≥30 mL/min/1.73 m2. These were then compared with the urinary albumin‐to‐creatinine ratio and eGFR.
Results
The serum and urinary KIM‐1 levels were significantly different among the three (eGFR ≥60, 45–59, <45 mL/min/1.73 m2) groups. These levels were positively associated with the albumin‐to‐creatinine ratio and negatively associated with eGFR. In a multivariate logistic model, both serum and urinary KIM‐1 were associated with an increased albumin‐to‐creatinine ratio (>30 mg/g Cr), but only the serum KIM‐1 was associated with a lower eGFR (<60 mL/min/1.73 m2), after adjustment for covariates.
Conclusions
Renal parameters appear to be strongly associated with serum KIM‐1, and not urinary KIM‐1, in patients with type 2 diabetes and an eGFR ≥30 mL/min/1.73 m2.
Both serum and urinary kidney injury molecule‐1 were associated with an increased albumin‐to‐creatinine ratio, but only serum kidney injury molecule‐1 was associated with a lower estimated glomerular filtration rate after adjustment for covariates in patients with type 2 diabetes and an estimated glomerular filtration rate ≥30 mL/min/1.73 m2.
Progranulin (PGRN), a growth factor, is abundantly expressed in a broad range of tissues and cell types with pleiotropic functions including inflammation, neurodegeneration, and facilitating lysosome ...acidification. PGRN binds to TNF receptors (TNFR) and inhibits downstream inflammatory signaling pathways. TNFR is a well-known predictor of glomerular filtration rate (GFR) decline in a variety of diseases. Therefore, we measured circulating PGRN in addition to TNFR using an enzyme-linked immunosorbent assay and explored whether it predicted renal prognosis in 201 Japanese patients with type 2 diabetes. During a median follow-up of 7.6 years, 21 participants reached primary renal endpoint, which involves a decline of at least 57% in eGFR from baseline, or the onset of end-stage renal disease. Univariate Cox regression analysis revealed that classical renal measures (GFR and albuminuria), two TNF-related biomarkers (PGRN and TNFR), and BMI were associated with this outcome. Multivariate analysis demonstrated that high levels of PGRN HR 2.50 (95%CI 2.47-2.52) or TNFR1 HR 5.38 (95%CI 5.26-5.50) were associated with this outcome after adjusting for relevant covariates. The high levels of PGRN as well as TNFR1 were associated with a risk of primary renal outcome in patients with type 2 diabetes after adjusting for established risk factors.
Comprehensive characterization of small-molecule degraders, including binary and ternary complex formation and degradation efficiency, is critical for bifunctional ligand development and ...understanding structure-activity relationships. Here, we present a protocol for the biochemical and cellular profiling of small-molecule degraders based on CoraFluor time-resolved fluorescence resonance energy transfer (TR-FRET) technology. We describe steps for labeling antibodies and proteins, tracer saturation binding, binary target engagement, ternary complex profiling, and off-rate determination. We then detail procedures for the quantification of endogenous and GFP fusion proteins in cell lysates.
For complete details on the use and execution of this protocol, please refer to Ichikawa et al.1
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•Comprehensive toolbox for systematically profiling proximity-inducing small molecules•Kinetic and thermodynamic analysis of binary and ternary ligand-target complexes•Quantitative characterization of ternary complex cooperativity (α) in high throughput•Facile quantification of endogenous and GFP fusion proteins in cell lysates
Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.
Comprehensive characterization of small-molecule degraders, including binary and ternary complex formation and degradation efficiency, is critical for bifunctional ligand development and understanding structure-activity relationships. Here, we present a protocol for the biochemical and cellular profiling of small-molecule degraders based on CoraFluor time-resolved fluorescence resonance energy transfer (TR-FRET) technology. We describe steps for labeling antibodies and proteins, tracer saturation binding, binary target engagement, ternary complex profiling, and off-rate determination. We then detail procedures for the quantification of endogenous and GFP fusion proteins in cell lysates.
L-carnitine is an important factor in fatty acid metabolism, and carnitine deficiency is common in dialysis patients. This study evaluated whether L-carnitine supplementation improved muscle spasm, ...cardiac function, and renal anemia in dialysis patients. Eighty Japanese outpatients (62 hemodialysis (HD) patients and 18 peritoneal dialysis (PD) patients) received oral L-carnitine (600 mg/day) for 12 months; the HD patients further received intravenous L-carnitine injections (1000 mg three times/week) for 12 months, amounting to 24 months of treatment. Muscle spasm incidence was assessed using a questionnaire, and cardiac function was assessed using echocardiography. Baseline free carnitine concentrations were relatively low in patients who underwent dialysis for >4 years. Total carnitine serum concentration, free carnitine, and acylcarnitine significantly increased after oral L-carnitine treatment for 12 months, and after intravenous L-carnitine injection. There was no significant improvement in muscle spasms, although decreased muscle cramping after L-carnitine treatment was reported by 31% of patients who had undergone HD for >4 years. Hemoglobin concentrations increased significantly at 12 and 24 months in the HD group. Therefore, L-carnitine may be effective for reducing muscle cramping and improving hemoglobin levels in dialysis patients, especially those who have been undergoing dialysis for >4 years.
Diabetic kidney disease (DKD) is among the most common and serious complications of both type 1 and type 2 diabetes. In this study, we used KK/Ta‐Ins2Akita (KK‐Akita) mice as a model of DKD and KK/Ta ...(KK) mice as controls to identify novel factors related to the development/progression of DKD. Capillary electrophoresis coupled with mass spectrometry analysis revealed that circulating Asp (l‐aspartic acid) levels in diabetic KK‐Akita mice tend to be lower than those in control KK mice. Therefore, we evaluated the effect of Asp supplementation to prevent the progression of DKD in KK‐Akita mice. Mice were divided into three groups: (a) untreated KK mice (Control group), (b) untreated KK‐Akita mice (DKD group), and (c) treated (double‐volume Asp diet) KK‐Akita mice (Tx group). Kidney sections were stained with fluorescein isothiocyanate‐labeled lectins, wheat germ agglutinin (WGA), and anti‐endothelial nitric oxide synthase (eNOS) antibody for evaluation of endothelial surface layer (ESL) and NO synthesis. The mesangial area and glomerular size in the DKD group were significantly larger than those in the Control group; however, there was no significant difference in those between the DKD and Tx groups. Albuminuria, the ratio of foot process effacement, and thickness of glomerular basement membrane in the Tx group were significantly lower than those in the DKD group. Furthermore, the expression levels of glomerular WGA and microvascular eNOS in the Tx group improved significantly and approached the level in the Control group. In conclusion, the improvement of albuminuria in the Tx group may be caused by the reduction of oxidative stress in the kidneys, which may lead to the subsequent improvement of glomerular ESL.
Serum aspartic acid (Asp) levels in KK‐Akita mice were lower than those in KK mice. Albuminuria was decreased, and the expression of glomerular wheat germ agglutinin and microvascular endothelial nitric oxide synthase was improved after Asp supplementation in KK‐Akita mice. These results may be caused by the reduction of oxidative stress in the kidneys, which may lead to the subsequent improvement of glomerular endothelial surface layer.
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