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ObjectivePrimary bilateral macronodular adrenal hyperplasia (PBMAH), a rare cause of Cushing syndrome, is often diagnosed as a bilateral adrenal incidentaloma with subclinical cortisol production. Circulating microRNAs (miRNAs) are a characteristic of adrenocortical adenomas, but miRNA expression in PBMAH has not been investigated. We aimed to evaluate the circulating miRNA expression in patients with PBMAH and compare them with those in patients with non-functioning adrenocortical adenoma (NFA) and cortisol-producing adrenocortical adenoma (CPA).MethodsmiRNA profiling of plasma samples from four, five, and five patients with NFA, CPA, and PBMAH, respectively, was performed. Selected miRNA expressions were validated using quantitative RT-PCR.ResultsPBMAH samples showed distinct miRNA expression signatures on hierarchical clustering while NFA and CPA samples were separately clustered. PBMAH was distinguished from the adenoma group of NFA and CPA by 135 differentially expressed miRNAs. Hsa-miR-1180-3p, hsa-miR-4732-5p, and hsa-let-7b-5p were differentially expressed between PBMAH and adenoma (P = 0.019, 0.006, and 0.003, respectively). Furthermore, PBMAH could be classified into two subtypes based on miRNA profiling: subtype 1 with a similar profile to those of adenoma and subtype 2 with a distinct profile. Hsa-miR-631, hsa-miR-513b-5p, hsa-miR-6805-5p, and hsa-miR-548av-5p/548k were differentially expressed between PBMAH subtype 2 and adenoma (P = 0.027, 0.027, 0.027, and 1.53E-04, respectively), but not between PBMAH, as a whole, and adenoma.ConclusionCirculating miRNA signature was identified specific for PBMAH. The existence of subtype-based miRNA profiles may be associated with the pathophysiological heterogeneity of PBMAH.

Adipose-derived stem cells are expected to be applied to regenerative medicine for various incurable diseases including liver cirrhosis. Although microRNAs contained in extracellular vesicles (EV-miRNAs) have been implicated in their regenerative effects, the precise mechanism has not been fully elucidated. Tamoxifen-inducible adipocyte-specific insulin receptor knockout (iFIRKO) mice are known to exhibit acute adipose tissue regeneration with increased numbers of adipose stem and progenitor cells (ASPCs). Because adipose tissue is the major source of circulating EV-miRNAs, we investigated alterations in serum EV-miRNAs in iFIRKO mice. A comprehensive analysis using miRNA sequencing on serum EVs revealed that most EV-miRNAs were decreased due to the loss of mature adipocytes, but there were 19 EV-miRNAs that were increased in the serum of iFIRKO mice. Among them, miR-144-3p and miR-486a-3p were found to be increased in the liver as well as serum EVs. While the expression levels of pri-miR-144-3p and pri-miR-486a-3p were not increased in the liver, they were elevated in the adipose tissue, suggesting that these miRNAs may be delivered from ASPCs increased in the adipose tissue to the liver via EVs. Increased hepatocyte proliferation was observed in the liver of iFIRKO mice, and we found that both miR-144-3p and miR-486a-3p have a function to promote hepatocyte proliferation by suppressing Txnip expression as a target gene. miR-144-3p and miR-486a-3p can be candidate therapeutic tools for conditions requiring hepatocyte proliferation, such as liver cirrhosis, and our current study suggests that examining EV-miRNAs secreted in vivo may lead to the discovery of miRNAs involved in regenerative medicine that have not been identified by in vitro analysis.

Objective Primary aldosteronism (PA) is a major cause of secondary hypertension and is associated with chronic renal injury. The glomerular filtration rate (GFR) in PA rapidly decreases after the removal of glomerular hyperfiltration due to aldosterone excess by adrenalectomy (ADX) or mineralocorticoid receptor antagonist (MRA) treatment and is stable in the long term. However, the effects of these treatments on the long‐term renal function of PA patients with chronic kidney disease (CKD) is not well understood. Design and Patients In this single‐center, retrospective study, acute and chronic changes in the estimated GFR (eGFR) were examined in 107 patients with PA, including 49 patients with post‐treatment CKD　defined as eGFR < 60 ml/min/1.73 m2. Results The reduction in eGFR observed 1 month after ADX in the CKD group (N = 31) was −20.1 ± 8.2 ml/min/1.73 m2. Multivariate analysis showed that pre‐treatment eGFR and plasma aldosterone concentration were independent predictive factors of the acute reduction in eGFR after ADX. The reduction of eGFR observed 1 month after MRA administration in the post‐treatment CKD group (N = 18) was −9.2 ± 5.9 ml/min/1.73 m2. Multivariate analysis showed that the duration of hypertension and pre‐treatment eGFR were independent predictive factors of the acute reduction in eGFR after ADX administration. In 20 patients with CKD (N = 12 ADX and N = 8 MRA) followed for more than 5 years post‐treatment, there was no further significant decline in eGFR over a follow‐up period of 7 (6, 8) years nor any difference between the two treatment modalities. Conclusions Our study suggests that treatment of PA in stage 3 CKD is safe and useful in preventing renal injury.