A novel indole compound MA-35 attenuates renal fibrosis by inhibiting both TNF-α and TGF-β1 pathways

Renal fibrosis is closely related to chronic inflammation and is under the control of epigenetic regulations. Because the signaling of transforming growth factor-β1 (TGF-β1) and tumor necrosis factor-α (TNF-α) play key roles in progression of renal fibrosis, dual blockade of TGF-β1 and TNF-α is desired as its therapeutic approach. Here we screened small molecules showing anti-TNF-α activity in the compound library of indole derivatives. 11 out of 41 indole derivatives inhibited the TNF-α effect. Among them, Mitochonic Acid 35 (MA-35), 5-(3, 5-dimethoxybenzyloxy)-3-indoleacetic acid, showed the potent effect. The anti-TNF-α activity was mediated by inhibiting IκB kinase phosphorylation, which attenuated the LPS/GaIN-induced hepatic inflammation in the mice. Additionally, MA-35 concurrently showed an anti-TGF-β1 effect by inhibiting Smad3 phosphorylation, resulting in the downregulation of TGF-β1-induced fibrotic gene expression. In unilateral ureter obstructed mouse kidney, which is a renal fibrosis model, MA-35 attenuated renal inflammation and fibrosis with the downregulation of inflammatory cytokines and fibrotic gene expressions. Furthermore, MA-35 inhibited TGF-β1-induced H3K4me1 histone modification of the fibrotic gene promoter, leading to a decrease in the fibrotic gene expression. MA-35 affects multiple signaling pathways involved in the fibrosis and may recover epigenetic modification; therefore, it could possibly be a novel therapeutic drug for fibrosis

Mitochonic Acid 5 (MA-5) Facilitates ATP Synthase Oligomerization and Cell Survival in Various Mitochondrial Diseases

Mitochondrial dysfunction increases oxidative stress and depletes ATP in a variety of disorders. Several antioxidant therapies and drugs affecting mitochondrial biogenesis are undergoing investigation, although not all of them have demonstrated favorable effects in the clinic. We recently reported a therapeutic mitochondrial drug mitochonic acid MA-5 (Tohoku J. Exp. Med., 2015). MA-5 increased ATP, rescued mitochondrial disease fibroblasts and prolonged the life span of the disease model “Mitomouse” (JASN, 2016). To investigate the potential of MA-5 on various mitochondrial diseases, we collected 25 cases of fibroblasts from various genetic mutations and cell protective effect of MA-5 and the ATP producing mechanism was examined. 24 out of the 25 patient fibroblasts (96%) were responded to MA-5. Under oxidative stress condition, the GDF-15 was increased and this increase was significantly abrogated by MA-5. The serum GDF-15 elevated in Mitomouse was likewise reduced by MA-5. MA-5 facilitates mitochondrial ATP production and reduces ROS independent of ETC by facilitating ATP synthase oligomerization and supercomplex formation with mitofilin/Mic60. MA-5 reduced mitochondria fragmentation, restores crista shape and dynamics. MA-5 has potential as a drug for the treatment of various mitochondrial diseases. The diagnostic use of GDF-15 will be also useful in a forthcoming MA-5 clinical trial

Ferroptosis in health and disease.

Ferroptosis is a pervasive non-apoptotic form of cell death highly relevant in various degenerative diseases and malignancies. The hallmark of ferroptosis is uncontrolled and overwhelming peroxidation of polyunsaturated fatty acids contained in membrane phospholipids, which eventually leads to rupture of the plasma membrane. Ferroptosis is unique in that it is essentially a spontaneous, uncatalyzed chemical process based on perturbed iron and redox homeostasis contributing to the cell death process, but that it is nonetheless modulated by many metabolic nodes that impinge on the cells susceptibility to ferroptosis. Among the various nodes affecting ferroptosis sensitivity, several have emerged as promising candidates for pharmacological intervention, rendering ferroptosis-related proteins attractive targets for the treatment of numerous currently incurable diseases. Herein, the current members of a Germany-wide research consortium focusing on ferroptosis research, as well as key external experts in ferroptosis who have made seminal contributions to this rapidly growing and exciting field of research, have gathered to provide a comprehensive, state-of-the-art review on ferroptosis. Specific topics include: basic mechanisms, in vivo relevance, specialized methodologies, chemical and pharmacological tools, and the potential contribution of ferroptosis to disease etiopathology and progression. We hope that this article will not only provide established scientists and newcomers to the field with an overview of the multiple facets of ferroptosis, but also encourage additional efforts to characterize further molecular pathways modulating ferroptosis, with the ultimate goal to develop novel pharmacotherapies to tackle the various diseases associated with - or caused by - ferroptosis

Gut Microbiota Dynamics and Uremic Toxins

Recent evidence has highlighted the importance of the gut microbiota in the pathophysiology of kidney diseases [...

What’s New in the Molecular Mechanisms of Diabetic Kidney Disease: Recent Advances

Diabetic kidney disease (DKD) is the leading cause of chronic kidney disease, including end-stage kidney disease, and increases the risk of cardiovascular mortality. Although the treatment options for DKD, including angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, sodium-glucose cotransporter 2 inhibitors, and mineralocorticoid receptor antagonists, have advanced, their efficacy is still limited. Thus, a deeper understanding of the molecular mechanisms of DKD onset and progression is necessary for the development of new and innovative treatments for DKD. The complex pathogenesis of DKD includes various different pathways, and the mechanisms of DKD can be broadly classified into inflammatory, fibrotic, metabolic, and hemodynamic factors. Here, we summarize the recent findings in basic research, focusing on each factor and recent advances in the treatment of DKD. Collective evidence from basic and clinical research studies is helpful for understanding the definitive mechanisms of DKD and their regulatory systems. Further comprehensive exploration is warranted to advance our knowledge of the pathogenesis of DKD and establish novel treatments and preventive strategies

CE-MS-Based Identification of Uremic Solutes Specific to Hemodialysis Patients

Uremic toxins are suggested to be involved in the pathophysiology of hemodialysis (HD) patients. However, the profile of uremic solutes in HD patients has not been fully elucidated. In this study using capillary electrophoresis mass spectrometry (CE-MS), we comprehensively quantified the serum concentrations of 122 ionic solutes before and after HD in 11 patients. In addition, we compared the results with those in non-HD patients with chronic kidney disease (CKD) to identify HD patient-specific solutes. We identified 38 solutes whose concentrations were higher in pre-HD than in CKD stage G5. Ten solutes among them did not significantly accumulate in non-HD CKD patients, suggesting that these solutes accumulate specifically in HD patients. We also identified 23 solutes whose concentrations were lower in both pre- and post-HD than in CKD stage G5. The serum levels of 14 solutes among them were not affected by renal function in non-HD patients, suggesting that these solutes tend to be lost specifically in HD patients. Our data demonstrate that HD patients have a markedly different profile of serum uremic solute levels compared to that in non-HD CKD patients. The solutes identified in our study may contribute to the pathophysiology of HD patients