Hickson, LaTonya J.

ABSTRACT Cellular senescence in the kidney plays a crucial role in the progression of acute kidney injury and chronic kidney disease. Therapeutic approaches targeting senescent cells, such as small molecule senolytic and senomorphic drugs, display efficacy in preclinical models. However, such drugs pose a risk of adverse effects and only partially mitigate disease progression, highlighting the need for new therapeutic approaches that more comprehensively and safely address disease pathways in aging kidney disease. This review discusses the potential of extracellular vesicles and longevity proteins, such as α‐klotho and silencing information regulator 2‐related enzyme 1 (SIRT1), in regulating cellular senescence and alleviating kidney fibrosis. Particularly, combination therapy that simultaneously targets inflammation, tissue damage, and senescence is promising for kidney disease, given the potential to synergistically overcome the limitations of current unimodular treatment modalities and pave the way for more effective management of kidney disease. This review highlights the mechanisms of cellular senescence in kidney disease, particularly in diabetic kidney disease, the latest knowledge on senotherapy, and the potential and challenges of new therapeutic strategies, including combining extracellular vesicles and longevity proteins.

Objective To quantitatively examine immune cell markers and spatial distribution in human diabetic kidney disease (DKD) to enhance understanding of the inflammatory landscape contributing to injury. Maladaptive inflammation is an underrecognized contributor to DKD pathogenesis and progression and remains undertreated. Patients and methods NanoString GeoMx™ Digital Spatial Profiling technology targeted antibodies labeled with unique oligonucleotide barcode in kidney biopsy [DKD (n=5), tubulointerstitial nephritis (TIN; n=4), and normal (n=2)] with regions of interest selection of compartments (glomeruli, tubules, interstitium). Inflammation-related proteins were analyzed with differential expression through linear mixed modeling. Results Compared to normal tissue, inflammatory cell surface protein markers were increased in DKD tubules and interstitium. Markers of T cells (CD4, CD44), macrophages (CD68; proinflammatory), and antigen-presenting cells (APCs; CD40 and CD11c) were increased across all DKD compartments (vs. normal). Macrophage (CD163; prorepair) marker was increased in DKD tubules and interstitium (vs. normal). Fewer differences were observed in glomeruli for normal vs. DKD or TIN vs. DKD groups. CD66b+ (granulocytes) cell marker was higher in DKD (vs. TIN). As expected, TIN had higher levels of T cell and macrophage markers in tubules and interstitium (vs. DKD). Interestingly, CD34, a hematopoietic stem cell and endothelial cell marker, was lower in DKD tubules and interstitium (vs. normal) but higher in DKD (vs. TIN). Conclusion NanoString GeoMx DSP technology may fulfil a role in enhancing the understanding the inflammatory landscape engaged in DKD pathogenesis as well as measuring response to therapy. Moreover, additional investigations of CD34 progenitor cell depletion in DKD may be warranted.

Key Points BeWell360-PKD shows that integrating certified health and wellness coaches and augmenting patients' personal capacity as part of autosomal dominant polycystic kidney disease care is feasible and acceptable. Embedding BeWell360 coaches reduced care burden, improved caregiver self-efficacy, and enhanced care engagement by patients with autosomal dominant polycystic kidney disease and by their informal caregivers. This aligns with evolving care standards and guidelines promoting sustainable healthy lifestyle changes through tailored, integrative behavior-change centered interventions. Background Autosomal dominant polycystic kidney disease (ADPKD) imposes substantial care burden on patients and their informal caregivers (CGs), often contributing to nonadherence and impaired quality of life. Existing care models insufficiently address the behavioral and psychosocial dimensions of this burden. To evaluate the feasibility and effect of BeWell360-PKD , a person-centered intervention integrating Health and Wellness Coaching and capacity-workload support into ADPKD care, on care burden, adherence, self-efficacy, activation, and resilience. Methods In this 6-month, single-arm, mixed-methods pilot study, seven patient-CG dyads were enrolled from tertiary care polycystic kidney disease clinic. Board-certified Health and Wellness Coachings delivered individualized coaching within routine nephrology care, emphasizing capacity-building, goal setting, and care enactment support. Primary outcomes included changes in treatment burden (treatment burden questionnaire, ADPKD impact scale) and CG burden (burden scale for family CGs short version). Secondary outcomes included patient activation and resilience and CG self-efficacy. Semistructured interviews explored participant experiences. Results Patients experienced reduced treatment burden (treatment burden questionnaire mean change −9.3) and modest, domain-specific improvements in physical and fatigue-related ADPKD symptom burden. CG self-efficacy improved (+2.4), while CG burden increased (+14.8), and patient activation declined (−6.6). Qualitative themes reflected disease burden, emotional adaptation, and the perceived value of coaching in promoting behavior change and relational support. Conclusions BeWell360-PKD was feasible to implement and demonstrated early signals of benefit in reducing patient burden and improving CG self-efficacy. Increased CG burden and declining activation highlight the complexity of dyadic adaptation in ADPKD and the need for larger, controlled studies to refine and tailor coaching interventions.

Key Points This study demonstrates that peritoneal dialysis is a safe and feasible option for patients with autosomal dominant polycystic kidney disease, even with high cystic organ volumes. Larger organ volumes, including height-adjusted cumulative kidney and liver volume, were not associated with increased peritoneal dialysis–related complications. Background Autosomal dominant polycystic kidney disease (ADPKD) is the most prevalent genetic kidney disorder and the fourth leading cause of kidney failure. Peritoneal dialysis (PD), preferred for its home-based convenience and cost-effectiveness, is often underutilized in ADPKD because of concerns over enlarged kidneys and heightened risk of complications. Methods This retrospective cohort study used data from the Mayo Clinic Polycystic Kidney Disease Database to evaluate individuals with ADPKD undergoing PD. We analyzed demographics, clinical parameters, and PD-related parameters. Complications were correlated with kidney and liver volumes derived from pre-kidney failure imaging. Results A total of 155 individuals with ADPKD on PD were included, of whom 45.1% were male. The mean age at PD initiation was 54.3±12.8 years, and the mean body mass index was 28.0±7.0 kg/m 2 . The median duration of PD was 24.3 months (interquartile range [IQR], 10.7–43.1), with 21.9% transitioning to hemodialysis. The most common complications were abdominal hernias (30.3%) and peritonitis (23.9%), with a peritonitis rate of 0.11 episodes per patient-year. Imaging analyses performed on a subset of 50 patients showed a median height-adjusted total kidney liver volume of 2731.9 ml/m (IQR, 2102.5–3131.1) and a median height-adjusted total kidney volume of 1303.5 ml/m (IQR, 733.1–1829.4). Kaplan–Meier analysis demonstrated no differences in complications rates on the basis of height-adjusted total kidney liver volume or height-adjusted total kidney volume (above versus below median values) or body mass index categories. Multivariate Cox regression analysis revealed that higher height-adjusted cumulative organ volume was associated with a lower risk of PD-related complications (hazard ratio=0.56, P = 0.026). Conclusions PD is a safe and feasible treatment option for patients with ADPKD, with no increased risk of PD-related complications associated with larger height-adjusted cumulative organ volumes. Infectious complication rates in this cohort were within International Society of Peritoneal Dialysis guideline thresholds, further supporting the safety of PD in this population.

Endothelial progenitor cells (EPCs) constitute a promising focus for research in regenerative medicine. These cells originate from the bone marrow and other circulating hematopoietic cells and regulate tissue regeneration and vascular integrity. EPC mobilization serves for neovascularization and re-endothelialization after injury in multiple organ systems, including the renal and cardiovascular systems. Both their number and function may vary in disease states such as CKD, depending on severity, comorbid conditions, and other factors. Therefore, circulating EPC count and function have been proposed as markers for vascular health, and their mobilization or replenishment may offer a potential therapy. Delivery of EPCs has shown success in repairing injured kidneys in animal models of both chronic and AKIs. This approach may be limited by EPC heterogeneity and incomplete characterization that may be addressed by standardization, engineering, or combination with other therapies. The aim of this article was to review the current state and recent advances in our understanding of the role of EPCs in homeostasis and conditions that may lead to their dysregulation in kidney diseases.

Key Points Activin A is implicated in profibrotic and prosenescent kidney injury and correlates with kidney injury markers in animals and humans. Follistatin, through activin A antagonism, reduces senescence burden, macrophage infiltration, and proinflammatory pathway activation in murine diabetic kidney disease. Follistatin and other antagonists of activin A signaling pathways may be promising, novel therapeutics for diabetic kidney disease. Background Circulating activin A, an inflammatory mediator implicated in profibrotic kidney injury and cellular senescence-induced adipose tissue dysfunction, is increased in human diabetic kidney disease (DKD) and directly correlates with kidney dysfunction. We tested the hypothesis that activin A increases kidney injury, senescent cell abundance, and macrophage infiltration in DKD and antagonism through follistatin (FS) therapy diminishes these effects. Methods An accelerated nephropathy type 2 diabetes (db/db) mouse model was generated by implantation of angiotensin II-loaded osmotic minipumps resulting in increased albuminuria and glomerular and tubular injury. Kidney repair effects of FS (5 µ g intraperitoneal; two doses) were assessed through markers of kidney injury, fibrosis, inflammation, cellular senescence, and macrophage infiltration. In vitro studies examined antiactivin effects of FS on high glucose-exposed human monocytes, renal fibroblasts, and renal tubule epithelial cells. Results Activin A antagonism with FS reduced senescence (p19), proinflammatory (including senescence-associated secretory phenotype), and profibrotic markers including activin A. FS improved kidney morphology, restored podocyte markers (nephrin and Wilms tumor-1), and reduced kidney injury biomarkers, albuminuria and kidney fibrosis. FS decreased kidney macrophage and leukocyte infiltration and absent in melanoma 2 inflammasome activation. FS seemed to suppress inflammation through the toll-like receptor-4/NF kappa-light-chain-enhancer of activated B cells pathway in vivo further supported in human macrophages in vitro . In addition, FS reduced hyperglycemia-induced renal fibroblast activation and renal tubule epithelial cell senescence in vitro . Conclusions Activin A is a mediator of kidney injury through macrophage-associated inflammation in murine DKD. FS acts through senomorphic activities which inhibit profibrotic, proinflammatory, and prosenescence signaling by activin A. Hence, antiactivin targeting may aid in the development of a promising, novel therapeutic for DKD.