Epiberberine ameliorated diabetic nephropathy by inactivating the angiotensinogen (Agt) to repress TGFβ/Smad2 pathway

Enhancing β-cell function and identity in type 2 diabetes: The protective role of Coptis deltoidea C. Y. Cheng et Hsiao via glucose metabolism modulation and AMPK signaling activation

BACKGROUND

Abnormalities in glucose metabolism may be the underlying cause of β-cell dysfunction and identity impairment resulting from high glucose exposure. In China, Coptis deltoidea C. Y. Cheng et Hsiao (YL) has demonstrated remarkable hypoglycemic effects.

HYPOTHESIS/PURPOSE

To investigate the hypoglycemic effect of YL and determine the mechanism of YL in treating diabetes.

METHODS

A type 2 diabetes mouse model was used to investigate the pharmacodynamics of YL. YL was administrated once daily for 8 weeks. The hypoglycemic effect of YL was assessed by fasting blood glucose, an oral glucose tolerance test, insulin levels, and other indexes. The underlying mechanism of YL was examined by targeting glucose metabolomics, western blotting, and qRT-PCR. Subsequently, the binding capacity between predicted AMP-activated protein kinase (AMPK) and important components of YL (Cop, Ber, and Epi) were validated by molecular docking and surface plasmon resonance. Then, in AMPK knockdown MIN6 cells, the mechanisms of Cop, Ber, and Epi were inversely confirmed through evaluations encompassing glucose-stimulated insulin secretion, markers indicative of β-cell identity, and the examination of glycolytic genes and products.

RESULTS

YL (0.9 g/kg) treatment exerted notable hypoglycemic effects and protected the structural integrity and identity of pancreatic β-cells. Metabolomic analysis revealed that YL inhibited the hyperactivated glycolysis pathway in diabetic mice, thereby regulating the products of the tricarboxylic acid cycle. KEGG enrichment revealed the intimate relationship of this process with the AMPK signaling pathway. Cop, Ber, and Epi in YL displayed high binding affinities for AMPK protein. These compounds played a pivotal role in preserving the identity of pancreatic β-cells and amplifying insulin secretion. The mechanism underlying this process involved inhibition of glucose uptake, lowering intracellular lactate levels, and elevating acetyl coenzyme A and ATP levels through AMPK signaling. The use of a glycolytic inhibitor corroborated that attenuation of glycolysis restored β-cell identity and function.

CONCLUSION

YL demonstrates significant hypoglycemic efficacy. We elucidated the potential mechanisms underlying the protective effects of YL and its active constituents on β-cell function and identity by observing glucose metabolism processes in pancreatic tissue and cells. In this intricate process, AMPK plays a pivotal regulatory role.

Biologically active isoquinoline alkaloids covering 2019-2022

Isoquinoline alkaloids are an important class of natural products that are abundant in the plant kingdom and exhibit a wide range of structural diversity and biological activities. With the deepening of research in recent years, more and more isoquinoline alkaloids have been isolated and identified and proved to contain a variety of biological activities and pharmacological effects. In this review, we introduce the research progress of isoquinoline alkaloids from 2019 to 2022, mainly in the part of biological activities, including antitumor, antimicrobial, antidiabetic, antiviral, anti-inflammatory, antioxidant, neuroprotective, hepatoprotective, analgesic, and other activities. This study provides a clear direction for the rational development and utilization of isoquinoline alkaloids, suggesting that these alkaloids have great potential in the field of drug research.

Biochanin A Ameliorates Nephropathy in High-Fat Diet/Streptozotocin-Induced Diabetic Rats: Effects on NF-kB/NLRP3 Axis, Pyroptosis, and Fibrosis

Nephropathy is the most prevalent microvascular disorder in diabetes mellitus. Oxidative stress and inflammatory cascade provoked by the persistent hyperglycemic milieu play integral roles in the aggravation of renal injury and fibrosis. We explored the impact of biochanin A (BCA), an isoflavonoid, on the inflammatory response, nod-like receptor protein 3 (NLRP3) inflammasome activation, oxidative stress, and fibrosis in diabetic kidneys. A high-fat-diet/streptozotocin (HFD/STZ)-induced experimental model of diabetic nephropathy (DN) was established in Sprague Dawley rats, and in vitro studies were performed in high-glucose-induced renal tubular epithelial (NRK-52E) cells. Persistent hyperglycemia in diabetic rats was manifested by perturbation of renal function, marked histological alterations, and oxidative and inflammatory renal damage. Therapeutic intervention of BCA mitigated histological changes, improved renal function and antioxidant capacity, and suppressed phosphorylation of nuclear factor-kappa B (NF-κB) and nuclear factor-kappa B inhibitor alpha (IκBα) proteins. Our in vitro data reveal excessive superoxide generation, apoptosis, and altered mitochondrial membrane potential in NRK-52E cells that were cultured in a high-glucose (HG) environment were subsided by BCA intervention. Meanwhile, the upregulated expressions of NLRP3 and its associated proteins, the pyroptosis-indicative protein gasdermin-D (GSDMD) in the kidneys, and HG-stimulated NRK-52E cells were significantly ameliorated by BCA treatment. Additionally, BCA blunted transforming growth factor (TGF)-β/Smad signaling and production of collagen I, collagen III, fibronectin, and alfa-smooth muscle actin (α-SMA) in diabetic kidneys. Our results indicate the plausible role of BCA in attenuating DN, presumably through modulation of the apoptotic cascade in renal tubular epithelial cells and the NF-κB/NLRP3 axis.

Epiberberine regulates lipid synthesis through SHP (NR0B2) to improve non-alcoholic steatohepatitis

Epiberberine (EPI), extracted from Rhizome Coptidis, has been shown to attenuate hyperlipidemia in vivo. Herein we have studied the mechanism by which EPI is active against non-alcoholic steatohepatitis (NASH) using, mice fed on a methionine- and choline-deficient (MCD) diet and HepG2 cells exposed to free fatty acids (FFA). We show that small heterodimer partner (SHP) protein is key in the regulation of lipid synthesis. In HepG2 cells and in the livers of MCD-fed mice, EPI elevated SHP levels, and this was accompanied by a reduction in sterol regulatory element-binding protein-1c (SREBP-1c) and FASN. Therefore, EPI reduced triglyceride (TG) accumulation in steatotic hepatocytes, even in HepG2 cells treated with siRNA-SHP, and also improved microbiota. Thus, EPI suppresses hepatic TG synthesis and ameliorates liver steatosis by upregulating SHP and inhibiting the SREBP1/FASN pathway, and improves gut microbiome.

Aqueous extract of Paeoniae Radix Alba (Paeonia lactiflora Pall.) ameliorates DSS-induced colitis in mice by tunning the intestinal physical barrier, immune responses, and microbiota

ETHNOPHARMACOLOGICAL RELEVANCE

Ulcerative colitis (UC) is a chronic non-specific intestinal inflammatory disease, the pathogenesis of which is strongly associated with the compromised intestinal barrier. Paeoniae Radix Alba (PRA), the root of Paeonia lactiflora Pall., is a well-known traditional Chinese medicine and an adaptogen used in Hozai, exhibiting appreciable anti-inflammatory and immunomodulatory activity. Nevertheless, the role and mechanism of PRA in UC have yet to be elucidated.

AIM OF THE STUDY

This study was set out to examine the ameliorative effects of the aqueous extract of PRA (i.e., PRA dispensing granule, PRADG) on dextran sulfate sodium (DSS)-induced colitis.

MATERIALS AND METHODS

The chemical components of PRADG was analyzed by HPLC. Colitis model mice were induced by free access to water containing 2.5% DSS for 10 consecutive days, and concurrently, PRADG (0.1025 and 0.41 g/kg) or Salazosulfapyridine (SASP, 450 mg/kg) was given orally from day 1-10. Body weight, disease activity index (DAI), colon length, histologic scoring, and inflammatory response were assessed. Additionally, IL-23/IL-17 axis and tight junction (TJ) proteins, as well as gut microbiota were also investigated under the above-mentioned regimen.

RESULTS

Eight main chemical constituents of CPT were revealed with HPLC analysis. Noticeably, PRADG could effectively lower body weight loss as well as DAI scores, alleviate colon shortening, and reduce the levels of proinflammatory cytokines in mice with colitis. Further exploration found that increment of TJ proteins expression (ZO-1, occludin and claudin-1) and inhibition of IL-23/IL-17 axis-modulated inflammation were observed in PRADG-treated mice. Additionally, the diversity of gut microbiota and the relative abundance of beneficial bacteria were increased following PRADG treatment.

CONCLUSIONS

PRADG could be sufficient to ameliorate colitis by regulating the intestinal physical barrier, immune responses, and gut microbiota in mice. Our findings highlight that PRADG might be a prospective remedy for UC.

Protective effects of Huang-Lian-Jie-Du Decoction on diabetic nephropathy through regulating AGEs/RAGE/Akt/Nrf2 pathway and metabolic profiling in db/db mice

BACKGROUND

Diabetic nephropathy (DN) is a severe diabetic complication that is the principal cause of end-stage kidney disease worldwide. Huang-Lian-Jie-Du Decoction (HLJDD) is widely used to treat diabetes clinically. However, the nephroprotective effects and potential mechanism of action of HLJDD against DN have not yet been fully elucidated.

PURPOSE

This study aimed to investigate the potential roles of HLJDD in DN and elucidate its mechanisms in db/db mice.

METHODS

An integrated strategy of network pharmacology, pharmacodynamics, molecular biology, and metabolomics was used to reveal the mechanisms of HLJDD in the treatment of DN. First, network pharmacology was utilized to predict the possible pathways for DN using the absorbed ingredients of HLJDD in rat plasma in silico. Then, combined with histopathological examination, biochemical evaluation immunohistochemistry/immunofluorescence assay, western blot analysis, and UPLC-Q-Orbitrap HRMS/MS-based metabolomics approach were applied to evaluate the efficacy of HLJDD against DN and its underlying mechanisms in vivo.

RESULTS

In silico, network pharmacology indicated that the AGEs/RAGE pathway was the most prominent pathway for HLJDD against DN. In vivo, HLJDD exerted protective effects against DN by ameliorating glycolipid metabolic disorders and kidney injury. Furthermore, we verified that HLJDD protected against DN by regulating the AGEs/RAGE/Akt/Nrf2 pathway for the first time. In addition, 22 potential biomarkers were identified in urine, including phenylalanine metabolism, tryptophan metabolism, glucose metabolism, and sphingolipid metabolism.

CONCLUSION

These findings suggest that HLJDD ameliorates DN by regulating the AGEs/RAGE/Akt/Nrf2 pathway and metabolic profiling.

Acute Proteomic Changes in Non-human Primate Kidney after Partial-body Radiation with Minimal Bone Marrow Sparing

Near total body exposure to high-dose ionizing radiation results in organ-specific sequelae, including acute radiation syndromes and delayed effects of acute radiation exposure. Among these sequelae are acute kidney injury and chronic kidney injury. Reports that neither oxidative stress nor inflammation are dominant mechanisms defining radiation nephropathy inspired an unbiased, discovery-based proteomic interrogation in order to identify mechanistic pathways of injury. We quantitatively profiled the proteome of kidney from non-human primates following 12 Gy partial body irradiation with 2.5% bone marrow sparing over a time period of 3 wk. Kidney was analyzed by liquid chromatography-tandem mass spectrometry. Out of the 3,432 unique proteins that were identified, we found that 265 proteins showed significant and consistent responses across at least three time points post-irradiation, of which 230 proteins showed strong upregulation while 35 proteins showed downregulation. Bioinformatics analysis revealed significant pathway and upstream regulator perturbations post-high dose irradiation and shed light on underlying mechanisms of radiation damage. These data will be useful for a greater understanding of the molecular mechanisms of injury in well-characterized animal models of partial body irradiation with minimal bone marrow sparing. These data may be potentially useful in the future development of medical countermeasures.