Xue Ting Han

With aging, the kidney undergoes inexorable and progressive changes in structural and functional performance. These aging-related alterations are more obvious and serious in diabetes mellitus (DM). Renal accelerated aging under DM conditions is associated with multiple stresses such as accumulation of advanced glycation end products (AGEs), hypertension, oxidative stress, and inflammation. The main hallmarks of cellular senescence in diabetic kidneys include cyclin-dependent kinase inhibitors, telomere shortening, and diabetic nephropathy-associated secretory phenotype. Lysosome-dependent autophagy and antiaging proteins Klotho and Sirt1 play a fundamental role in the accelerated aging of kidneys in DM, among which the autophagy-lysosome system is the convergent mechanism of the multiple antiaging pathways involved in renal aging under DM conditions. Metformin and the inhibitor of sodium–glucose cotransporter 2 are recommended due to their antiaging effects independent of antihyperglycemia, besides angiotensin-converting enzyme inhibitors/angiotensin receptor blockers. Additionally, diet intervention including low protein and low AGEs with antioxidants are suggested for patients with diabetic nephropathy (DN). However, their long-term benefits still need further study. Exploring the interactive relationships among antiaging protein Klotho, Sirt1, and autophagy-lysosome system may provide insight into better satisfying the urgent medical needs of elderly patients with aging-related DN.

Objective. Understanding the multifactorial changes involved in the kidney and heart after acute myocardial infarction (AMI) is prerequisite for further mechanisms and early intervention, especially autophagy changes. Here, we discussed the role of adaptive autophagy in the heart and kidney of rats with AMI. Methods. A rat model of AMI was established by ligating the left anterior descending branch of the coronary artery. Animals were sacrificed at 2 and 4 weeks after the operation to assess the morphological and functional changes of the heart and kidney, as well as the autophagy pathway. In vitro, HK-2 and AC16 cell injuries and the autophagy pathway were assayed after autophagy was inhibited by 3-methyladenine (3-MA) in a hypoxia incubator. Results. We found that the left ventricular systolic pressure (LVSP) significantly decreased in the model group at weeks 2 and 4. At weeks 2 and 4, the level of urinary kidney injury molecule 1 (uKIM1) of the model group was significantly higher than the sham group. At week 4, urinary neutrophil gelatinase-associated lipocalcin (uNGAL) and urinary albumin also significantly increased. At week 2, microtubule-associated protein 1 light chain 3-II (LC3-II), ATG5, and Beclin1 were significantly elevated in the heart and kidney compared with the sham-operated rats, but there was no change in p62 levels. At week 4, LC3-II did not significantly increase and p62 levels significantly increased. In addition, 3-MA markedly increased KIM1, NGAL, and the activity of caspase-3 in the hypoxic HK-2 and AC16 cell. Conclusion. Autophagy will undergo adaptive changes and play a protective role in the heart and kidney of rats after AMI.

Hypertensive renal injury is a primary etiology of end‐stage renal disease, and satisfactory therapeutic strategies are urgently required. Cordyceps cicadae, a traditional Chinese herb, has potential renoprotective benefits and is widely used in the treatment of many kidney diseases. To investigate the mechanisms underlying the renoprotective effect of C. cicadae on hypertensive renal injury, we studied the effect of C. cicadae on tubular epithelial cells (TECs) in a spontaneously hypertensive rat (SHR) model and angiotensin II‐ (AngII‐) cultured primary TECs. Our study showed that C. cicadae treatment could decrease 24‐hour urine albumin, albumin‐to‐creatinine ratio (ACR), β2‐MG level, and kidney injury molecule‐1 (kim‐1) level in SHR urine, alleviate interstitial fibrosis, and reduce α‐smooth muscle actin (α‐SMA) expression in SHR kidney. In primary TECs, medicated serum containing C. cicadae (CSM) might significantly reduce the AngII‐induced production of kim‐1 and neutrophil gelatinase‐associated lipocalin (NGAL). Furthermore, C. cicadae treatment could decrease TEC apoptosis in SHRs as assessed by the terminal transferase‐mediated biotin dUTP nick‐end labeling (TUNEL) assay. CSM could inhibit caspase‐3 activity and enhance cellular viability as measured by methyl thiazolyl tetrazolium in AngII‐cultured TECs, suggesting that CSM might reduce the apoptosis level in TECs induced by AngII. We found that the SIRT1 expression level was markedly lowered, while the protein level of acetylated‐p53 was elevated in the TECs of patients with hypertensive renal injury and SHRs. C. cicadae presented the effect of regulating the SIRT1/p53 pathway. Further SIRT1 inhibition with EX527 reversed the effect of C. cicadae on AngII‐induced apoptosis. Taken together, our results indicate that C. cicadae offers a protective effect on TECs under hypertensive conditions, which may be related to its antiapoptotic effect through regulation of the SIRT1/p53 pathway.

Chronic kidney disease (CKD) is a worldwide health problem for which effective therapeutic methods are still lacking. Traditional Chinese medicine (TCM) has been indicated as an effective alternative treatment for kidney disease. In this study, a clinically effective therapy, yiqihuoxue (YQHX) formula, was administrated to adenine-induced kidney disease rats for 6 weeks. We found that the adenine rats displayed a significant reduction in renal function as evidenced by the increased levels of serum creatinine (Scr), blood urea nitrogen (BUN), and 24-h urinary albumin level, which were attenuated by the YQHX treatment. The glomerulosclerosis, interstitial fibrosis, arteriolosclerosis, interstitial inflammation, and tubular dilatation were reversed by the YQHX treatment in the adenine rats. Furthermore, the hepatic damage characterized by increased levels of aspartate aminotransferase and alanine aminotransferase and inflammatory cell infiltration was improved by YQHX. In addition, the number of apoptotic cells in the adenine rats was obviously reduced by the YQHX treatment as manifested by the lower expression level of cleaved caspase-3 protein. Moreover, the YQHX treatment downregulated the expression levels of fibronectin, type I collagen, α-smooth muscle actin, and TGF-β1 in the adenine rats. Furthermore, autophagy was activated by the YQHX treatment, which manifested as an increased LC3-II and Beclin-1 expression levels and a decreased p62 level. In conclusion, the YQHX formula might retard the progression of kidney disease by activating autophagy.