Effects and mechanisms of total flavones of Abelmoschus manihot in attenuating diabetic tubulopathy by targeting endoplasmic reticulum stress-induced cell apoptosis / 中国中药杂志

Renal tubular injury in patients with diabetic kidney disease(DKD) may be accompanied by glomerular and microvascular diseases. It plays a critical role in the progression of renal damage in DKD, and is now known as diabetic tubulopathy(DT). To explore the multi-targeted therapeutic effects and pharmacological mechanisms in vivo of total flavones of Abelmoschus manihot(TFA), an extract from traditional Chinese medicine for treating kidney disease, in attenuating DT, the authors randomly divided all rats into four groups: a normal control group(normal group), a DT model group(model group), a DT model+TFA-treated group(TFA group) and a DT model+rosiglitazone(ROS)-treated group(ROS group). The DT rat model was established based on the DKD rat model by means of integrated measures. After successful modeling, the rats in the four groups were continuously given double-distilled water, TFA suspension, and ROS suspension, respectively by gavage every day. After 6 weeks of treatment, all rats were sacrificed, and the samples of their urine, blood, and kidneys were collected. The effects of TFA and ROS on various indicators related to urine and blood biochemistry, renal tubular injury, renal tubular epithelial cell apoptosis and endoplasmic reticulum stress(ERS), as well as the activation of the protein kinase R-like endoplasmic reticulum kinase(PERK)-eukaryotic translation initiation factor 2α(eIF2α)-activating transcription factor 4(ATF4)-C/EBP homologous protein(CHOP) signaling pathway in the kidney of the DT model rats were investigated. The results indicated that hypertrophy of renal tubular epithelial cells, renal tubular hyperplasia and occlusion, as well as interstitial extracellular matrix and collagen deposition occurred in the DT model rats. Moreover, significant changes were found in the expression degree and the protein expression level of renal tubular injury markers. In addition, there was an abnormal increase in tubular urine proteins. After TFA or ROS treatment, urine protein, the characteristics of renal tubular injury, renal tubular epithelial cell apoptosis and ERS, as well as the activation of the PERK-eIF2α-ATF4-CHOP signaling pathway in the kidney of the DT model rats were improved to varying degrees. Therein, TFA was superior to ROS in affecting the pathological changes in renal tubule/interstitium. In short, with the DT model rats, this study demonstrated that TFA could attenuate DT by multiple targets through inhibiting renal tubular ERS-induced cell apoptosis in vivo, and its effect and mechanism were related to suppressing the activation of the PERK-eIF2α-ATF4-CHOP signaling pathway in the kidney. These findings provided preliminary pharmacological evidence for the application of TFA in the clinical treatment of DT.

Effects and mechanisms of total flavones of Abelmoschus manihot in improving insulin resistance and podocyte epithelial-mesenchymal transition in diabetic kidney disease based on IRS1/PI3K/Akt pathway / 中国中药杂志

This study aimed to explore the effects and mechanisms of total flavones of Abelmoschus manihot(TFA), the extracts from traditional Chinese medicine indicated for kidney diseases, on insulin resistance(IR) and podocyte epithelial-mesenchymal transition(EMT) in diabetic kidney disease(DKD), and further to reveal the scientific connotation. Thirty-two rats were randomly divided into a normal group, a model group, a TFA group, and a rosiglitazone(ROS) group. The modified DKD model was induced in rats by methods including high-fat diet feeding, unilateral nephrectomy, and streptozotocin(STZ) intraperitoneal injection. After modeling, the rats in the four groups were given double-distilled water, TFA suspension, and ROS suspension correspondingly by gavage every day. At the end of the 8th week of drug administration, all rats were sacrificed, and the samples of urine, blood, and kidney tissues were collected. The parameters and indicators related to IR and podocyte EMT in the DKD model rats were examined and observed, including the general condition, body weight(BW) and kidney weight(KW), the biochemical parameters and IR indicators, the protein expression levels of the key signaling molecules and structural molecules of slit diaphragm in the renal insulin receptor substrate(IRS) 1/phosphatidylinositol 3-kinase(PI3K)/serine-threonine kinase(Akt) pathway, foot process form and glomerular basement membrane(GBM) thickness, the expression of the marked molecules and structural molecules of slit diaphragm in podocyte EMT, and glomerular histomorphological characteristics. The results showed that for the DKD model rats, both TFA and ROS could improve the general condition, some biochemical parameters, renal appearance, and KW. The ameliorative effects of TFA and ROS were equivalent on BW, urinary albumin(UAlb)/urinary creatinine(UCr), serum creatinine(Scr), triglyceride(TG), and KW. Secondly, they could both improve IR indicators, and ROS was superior to TFA in improving fast insulin(FIN) and homeostasis model assessment of insulin resistance(HOMA-IR). Thirdly, they could both improve the protein expression levels of the key signaling molecules in the IRS1/PI3K/Akt pathway and glomerulosclerosis in varying degrees, and their ameliorative effects were similar. Finally, both could improve podocyte injury and EMT, and TFA was superior to ROS. In conclusion, this study suggested that podocyte EMT and glomerulosclerosis could be induced by IR and the decreased activation of the IRS1/PI3K/Akt pathway in the kidney in DKD. Similar to ROS, the effects of TFA in inhibiting podocyte EMT in DKD were related to inducing the activation of the IRS1/PI3K/Akt pathway and improving IR, which could be one of the scientific connotations of TFA against DKD. This study provides preliminary pharmacological evidence for the development and application of TFA in the field of diabetic complications.

Effects and mechanisms of Supplemented Gegen Qinlian Decoction Formula against podocyte pyroptosis and insulin resistance in model rats with diabetic kidney disease / 中国中药杂志

This study explored the in vivo effects and mechanisms of the modern classical prescription Supplemented Gegen Qinlian Decoction Formula(SGDF) against diabetic kidney disease(DKD). Sixty rats were randomly divided into the normal group, model group, SGDF group, and rosiglitazone(ROS) group. The modified DKD rat model was established by employing the following three methods: exposure to high-fat diet, unilateral nephrectomy, and intraperitoneal injection of streptozotocin(STZ). After modeling, rats in the four groups were treated with double distilled water, SGDF suspension, and ROS suspension, respectively, by gavage every day. At the end of the 6 th week of drug administration, all the rats were sacrificed for collecting urine, blood, and kidney tissue, followed by the examination of rat general conditions, urine and blood biochemical indicators, glomerulosclerosis-related indicators, podocyte pyroptosis markers, insulin resistance(IR)-related indicators, and key molecules in the insulin receptor substrate(IRS) 1/phosphatidylinositol-3-kinase(PI3 K)/serine threonine kinase(Akt) signaling pathway. The results showed that SGDF and ROS improved the general conditions, some renal function indicators and glomerulosclerosis of DKD model rats without affecting the blood glucose(BG). Besides, they ameliorated the expression characteristics and levels of podocyte pyroptosis markers, alleviated IR, and up-regulated the protein expression levels of the key molecules in IRS1/PI3 K/Akt pathway to varying degrees. In conclusion, similar to ROS, SGDF relieves DKD by targeting multiple targets in vivo. Specifically, it exerts the therapeutic effects by alleviating podocyte pyroptosis and IR. This study has preliminarily provided the pharmacological evidence for the research and development of new drugs for the treatment of DKD based on SGDF.

Low dose of triptolide ameliorates podocyte epithelial-mesenchymal transition induced by high dose of D-glucose via inhibiting Wnt3α/β-catenin signaling pathway activation / 中国中药杂志

To explore the effects and molecular mechanisms of triptolide（TP）on improving podocyte epithelial-mesenchymal transition（EMT）induced by high dose of D-glucose（HG）, the immortalized podocytes of mice were divided into the normal group（N）, the high dose of D-glucose group（HG）, the low dose of TP group（L-TP）, the high dose of TP group（H-TP）and the mannitol group（MNT）, and treated by the different measures respectively. More specifically, the podocytes in each group were separately treated by D-glucose（DG, 5 mmol·L⁻¹）or HG（25 mmol·L⁻¹）or HG（25 mmol·L⁻¹）+ TP（3 μg·L⁻¹）or HG（25 mmol·L⁻¹）+ TP（10 μg·L⁻¹）or DG（5 mmol·L⁻¹）+ MNT（24.5 mmol·L⁻¹）. After the intervention for 24, 48 and 72 hours, firstly, the activation of podocyte proliferation was investigated. Secondly, the protein expression levels of the epithelial markers in podocytes such as nephrin and podocin, the mesenchymal markers such as desmin and collagen Ⅰ and the EMT-related mediators such as snail were detected respectively. Finally, the protein expression levels of Wnt3α and β-catenin as the key signaling molecules in Wnt3α/β-catenin pathway were examined severally. The results indicated that, HG could cause the low protein expression levels of nephrin and podocin and the high protein expression levels of desmin, collagen Ⅰ and snail in podocytes, and inducing podocyte EMT. On the other hand, HG could cause the high protein expression levels of Wnt3α and β-catenin in podocytes, and activating Wnt3α/β-catenin signaling pathway. In addition, L-TP had no effect on the activation of podocyte proliferation, the co-treatment of L-TP and HG could significantly recover the protein expression levels of nephrin and podocin, inhibit the protein expression levels of desmin, collagen I and snail in podocytes, thus, further improving podocyte EMT. And that, the co-treatment of L-TP and HG could obviously decrease the high protein expression levels of Wnt3α and β-catenin induced by HG in podocytes, and inhibit Wnt3α/β-catenin signaling pathway activation. On the whole, HG can induce podocyte EMT by activating Wnt3α/β-catenin signaling pathway; L-TP can ameliorate podocyte EMT through inhibiting Wnt3α/β-catenin signaling pathway activation, which may be one of the effects and molecular mechanisms .

Molecular regulative mechanisms of aging and interventional effects of Chinese herbal medicine / 中国中药杂志

Aging is a gradual process during the loss of functions in cells,organs and tissues by time. The molecular mechanisms of aging-related theories include the classical ones such as telomere,oxygen radical and nonenzymatic glycosylation,as well as the newly proposed ones such as DNA methylation,mitochondrial DNA （mtDNA）and autophagy. The latest study showed the anti-aging effect of autophagy in hematopoietic stem cells. In recent years,based on the molecular regulative mechanisms of aging,a number of the promising anti-aging drugs have been found,including nicotinamide mononucleotide（NMN）and FOXO4-DRI,a peptide of anti-aging. In addition,there are many new discoveries in the field of plant extracts,in which,the extracts from Chinese herbal medicine（CHM）,some single CHMs and the classical prescriptions of CHM,represented by curcumin and resveratrol,have the partial anti-aging effects by regulating the molecular mechanisms of aging both in vivo and in vitro. In brief,developing or exploring anti-aging drugs,especially the natural drugs,is one of the main development directions in the field of anti-aging research in the basis of the molecular regulative mechanisms of aging.