Diosgenin Modulates Oxidative Stress and Inflammation in High-Fat Diet-Induced Obesity in Mice

Diosgenin Reduces Acute Kidney Injury and Ameliorates the Progression to Chronic Kidney Disease by Modifying the NOX4/p65 Signaling Pathways

Acute kidney injury (AKI), if not well controlled, may progress to chronic kidney disease (CKD). Diosgenin is a natural phytosteroid sapogenin from plants. This study aimed to investigate the mechanistic effects of diosgenin on AKI and AKI related development of CKD. The mouse model of ischemia/reperfusion (I/R)-induced AKI was used, and its progressive changes were followed. Human renal proximal tubular epithelial cells were used, and hypoxia stimulation was applied to mimic the in vivo I/R. Diosgenin, given after renal injury, preserved kidney function, as evidenced by a reduction in serum levels of BUN, creatinine, and UACR in both acute and chronic phases of AKI. Diosgenin alleviated I/R-induced tubular injury and prevented macrophage infiltration and renal fibrosis in AKI mice. Furthermore, diosgenin also mitigated the development of CKD from AKI with reduced renal expression of inflammatory, fibrotic, and epithelial-mesenchymal transition markers. In human renal tubular epithelial cells, diosgenin downregulated the hypoxia-induced oxidative stress and cellular damages that were dependent on the NOX4/p65 signaling pathways. Taken together, diosgenin treatment reduced I/R-induced AKI and ameliorated the progression to CKD from AKI probably by modifying the NOX4/p65 signaling pathways.

Assessment and comparative study of diosgenin doses in alleviating experimental periodontitis

BACKGROUND

This study was performed to determine the therapeutic effects of diosgenin (DG) which is a steroidal saponin, administered at different doses on alveolar bone loss (ABL) in rats with experimental periodontitis using immunohistochemical and cone-beam computed tomography (CBCT).

METHODS

Thirty-two male Wistar rats divided into four equal groups: control (non-ligated), periodontitis (P), DG-48, and DG-96. Sutures were placed at the gingival margin of the lower first molars to induce experimental periodontitis. Then, 48 and 96 mg/kg of DG was administered to the study groups by oral gavage for 29 days. At day 30, the animals were sacrificed and ABL was determined via CBCT. The expression patterns of osteocalcin (OCN), alkaline phosphatase (ALP), type I collagen (Col-1), B cell lymphoma 2 (Bcl 2), Bcl 2-associated X protein (Bax), bone morphogenetic protein 2 (BMP-2), and receptor activator of NF κB ligand (RANKL) were examined immunohistochemically.

RESULTS

Histopathologic examination showed all features of the advanced lesion in the P group. DG use decreased all these pathologic changes. It was observed that periodontitis pathology decreased as the dose increased. DG treatment increased the ALP, OCN, Bcl 2, Col-1, and BMP-2 levels in a dose-dependent manner, compared with the P group (p < 0.05). DG decreased the expression of RANKL and Bax in a dose-dependent manner (p < 0.05). ABL was significantly lower in the DG-48 and DG-96 groups than in the P group (p < 0.05).

CONCLUSION

Collectively, our findings suggest that DG administration protects rats from periodontal tissue damage with a dose-dependent manner, provides an increase in markers of bone formation, decreases in Bax/Bcl-2 ratio and osteoclast activation.

Saponin monomers: Potential candidates for the treatment of type 2 diabetes mellitus and its complications

Type 2 diabetes mellitus (T2DM), a metabolic disease with persistent hyperglycemia primarily caused by insulin resistance (IR), has become one of the most serious health challenges of the 21st century, with considerable economic and societal implications worldwide. Considering the inevitable side effects of conventional antidiabetic drugs, natural ingredients exhibit promising therapeutic efficacy and can serve as safer and more cost-effective alternatives for the management of T2DM. Saponins are a structurally diverse class of amphiphilic compounds widely distributed in many popular herbal medicinal plants, some animals, and marine organisms. There are many saponin monomers, such as ginsenoside compound K, ginsenoside Rb1, ginsenoside Rg1, astragaloside IV, glycyrrhizin, and diosgenin, showing great efficacy in the treatment of T2DM and its complications in vivo and in vitro. However, although the mechanisms of action of saponin monomers at the animal and cell levels have been gradually elucidated, there is a lack of clinical data, which hinders the development of saponin-based antidiabetic drugs. Herein, the main factors/pathways associated with T2DM and the comprehensive underlying mechanisms and potential applications of these saponin monomers in the management of T2DM and its complications are reviewed and discussed, aiming to provide fundamental data for future high-quality clinical studies and trials.

Diosgenin as a substitute for cholesterol alleviates NAFLD by affecting CYP7A1 and NPC1L1-related pathway

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) rapidly becomes the leading cause of end-stage liver disease or liver transplantation. Nowadays, there has no approved drug for NAFLD treatment. Diosgenin as the structural analogue of cholesterol attenuates hypercholesterolemia by inhibiting cholesterol metabolism, which is an important pathogenesis in NAFLD progression. However, there has been no few report concerning its effects on NAFLD so far.

METHODS

Using a high-fat diet & 10% fructose-feeding mice, we evaluated the anti-NAFLD effects of diosgenin. Transcriptome sequencing, LC/MS analysis, molecular docking simulation, molecular dynamics simulations and Luci fluorescent reporter gene analysis were used to evaluate pathways related to cholesterol metabolism.

RESULTS

Diosgenin treatment ameliorated hepatic dysfunction and inhibited NAFLD formation including lipid accumulation, inflammation aggregation and fibrosis formation through regulating cholesterol metabolism. For the first time, diosgenin was structurally similar to cholesterol, down-regulated expression of CYP7A1 and regulated cholesterol metabolism in the liver (p < 0.01) and further affecting bile acids like CDCA, CA and TCA in the liver and feces. Besides, diosgenin decreased expression of NPC1L1 and suppressed cholesterol transport (p < 0.05). Molecular docking and molecular dynamics further proved that diosgenin was more strongly bound to CYP7A1. Luci fluorescent reporter gene analysis revealed that diosgenin concentration-dependently inhibited the enzymes activity of CYP7A1.

CONCLUSION

Our findings demonstrated that diosgenin was identified as a specific regulator of cholesterol metabolism, which pave way for the design of novel clinical therapeutic strategies.

Diosgenin Alleviates Obesity-Induced Insulin Resistance by Modulating PI3K/Akt Signaling Pathway in Mice Fed a High-Fat Diet

Obesity is a global medical issue that can be effectively treated by relieving adipose inflammation and subsequent insulin resistance. Diosgenin (DIOS) has various effects as a steroidal saponin in inflammatory disorders. This study explored the effects and mechanism of DIOS on adipose inflammation and insulin sensitivity, both in silico and in vivo. The high-fat diet-induced obesity model in C57BL/6 mice was divided into five groups: normal chow (NC), high-fat diet (HFD), HFD with atorvastatin 10 mg/kg (AT), HFD with DIOS 100 mg/kg (DIOS 100), and HFD with DIOS 200 mg/kg (DIOS 200). Each group underwent an oral intervention for seven weeks. DIOS significantly suppressed weight gain in the body, liver, and epididymal fat pads. Additionally, it significantly improved fasting glucose and insulin levels, homeostatic model assessment of insulin resistance (HOMA-IR), and oral glucose tolerance test results, and reduced the proportion of total and M1 adipose tissue macrophages. Significant changes were shown in mRNA expression of janus kinase 2 (JAK2), insulin receptor (INRS), insulin receptor substrate 1 (IRS-1), phosphatidylinositol 3-kinase (PI3K), and protein kinase B (Akt), all of which exhibited high binding affinity in the in silico. Safety indices, including aspartate aminotransferase (AST), alanine transaminase (ALT), and creatinine level indicated the preventive effects of DIOS. In conclusion, DIOS improves insulin resistance and obesity-associated inflammation via the PI3K/Akt signaling pathway.