Study on the mechanism of lupenone for treating type 2 diabetes by integrating pharmacological evaluation and network pharmacology

Lupenone improves motor dysfunction in spinal cord injury mice through inhibiting the inflammasome activation and pyroptosis in microglia via the nuclear factor kappa B pathway

JOURNAL/nrgr/04.03/01300535-202408000-00034/figure1/v/2023-12-16T180322Z/r/image-tiff Spinal cord injury-induced motor dysfunction is associated with neuroinflammation. Studies have shown that the triterpenoid lupenone, a natural product found in various plants, has a remarkable anti-inflammatory effect in the context of chronic inflammation. However, the effects of lupenone on acute inflammation induced by spinal cord injury remain unknown. In this study, we established an impact-induced mouse model of spinal cord injury, and then treated the injured mice with lupenone (8 mg/kg, twice a day) by intraperitoneal injection. We also treated BV2 cells with lipopolysaccharide and adenosine 5'-triphosphate to simulate the inflammatory response after spinal cord injury. Our results showed that lupenone reduced IκBα activation and p65 nuclear translocation, inhibited NLRP3 inflammasome function by modulating nuclear factor kappa B, and enhanced the conversion of proinflammatory M1 microglial cells into anti-inflammatory M2 microglial cells. Furthermore, lupenone decreased NLRP3 inflammasome activation, NLRP3-induced microglial cell polarization, and microglia pyroptosis by inhibiting the nuclear factor kappa B pathway. These findings suggest that lupenone protects against spinal cord injury by inhibiting inflammasomes.

Utilizing molecular docking and cell validation to explore the potential mechanisms of lupenone attenuating the inflammatory response via NF-κB pathway

Diabetic nephropathy (DN), a common microvascular complicating disease of diabetes. Lupenone, a pentacyclic triterpenoid, has anti-inflammatory effects and can prevent type 2 diabetes mellitus and treat renal damage, however, the effects and mechanisms of lupenone in DN remain unclear. Thereby,the MTT method was used to investigate the antiproliferative effect of lupenoneon the cell line rat glomerular mesangial cells (HBZY-1). Molecular docking was used to investigate the combination of lupenone and MCP-1, IL-1β, TNF-α, IKKβ, IκBα, and NF-κB p65 proteins. The expression of mRNA of the pro-inflammatory cytokines (MCP-1, IL-1β and TNF-α) and the NF-κB signalling pathway in HBZY-1 cells were assessed by RT-PCR. The protein expressions of pro-inflammatory cytokines and NF-κB pathway were got by Western blot. Result showed that lupenone inhibited the proliferative activity of HBZY-1 cells at non-cytotoxic concentrations. Molecular docking results showed that lupenone combined well with the target proteins. Moreover, lupenone could significantly reduced the mRNA and protein expressions for pro-inflammatory cytokines and IKKβ, p-p65 and p-IκBα. Lupenone may play an anti-inflammatory role in DN treatment by inhibiting the NF-κB signalling pathway. These results provided a new understanding of the pharmacological mechanisms of lupenone in treatment of DN.

Screening compounds for treating the diabetes and COVID-19 from Miao medicine by molecular docking and bioinformatics

Both diabetes and Corona Virus Disease 2019 (COVID-19) are seriously harmful to human health, and they are closely related. It is of great significance to find drugs that can simultaneously treat diabetes and COVID-19. Based on the theory of traditional Chinese medicine for treating COVID-19, this study first sorted out the compounds of Guizhou Miao medicine with "return to the lung channel" and "clear heat and detoxify" effects in China. The active components against COVID-19 were screened by molecular docking with SARS-CoV-2 PLpro and angiotensin-converting enzyme II as targets. Furthermore, the common target dipeptidyl peptidase 4 (DPP4) of diabetes and COVID-19 was used as a screening protein, and molecular docking was used to obtain potential components for the treatment of diabetes and COVID-19. Finally, the mechanism of potential ingredients in the treatment of diabetes and COVID-19 was explored with bioinformatics. More than 80 kinds of Miao medicine were obtained, and 584 compounds were obtained. Further, 110 compounds against COVID-19 were screened, and top 6 potential ingredients for the treatment of diabetes and COVID-19 were screened, including 3-O-β-D-Xylopyranosyl-(1-6)-β-D-glucopyranosyl-(1-6)-β-D-glucopyranosyl oleanolic acid 28-O-β-D-glucopyranosyl ester, Glycyrrhizic acid, Sequoiaflavone, 2-O-Caffeoyl maslinic acid, Pholidotin, and Ambewelamide A. Bioinformatics analysis found that their mechanism of action in treating diabetes and COVID-19 may be related to regulating the expression of DPP4, angiotensin II type 1 receptor, vitamin D receptor, plasminogen, chemokine C-C-motif receptor 6, and interleukin 2. We believe that Guizhou Miao medicine is rich in potential ingredients for the treatment of diabetes and COVID-19.

Lupenone-Rich Fraction Derived from Cissus quadrangularis L. Suppresses Lipid Accumulation in 3T3-L1 Adipocytes

Cissus quadrangularis L. (CQ) has potential as a therapeutic for managing obesity and balancing metabolic activity, but the main bioactive compound and regulatory mechanism remain unknown. Herein, the CQ hexane extract was fractionated into 30 fractions (CQ-H) using flash column chromatography and analyzed using thin-layer chromatography. The direct antiadipogenesis effect of CQ-H fractions was tested on 3T3-L1 preadipocytes. Lupenone-rich fractions 2H and 3H were identified as containing potent antiadipogenesis agents that reduced differentiated cell numbers and intracellular lipid droplet size. Although the overall mitochondrial density remained unchanged, differentiated cells exhibited a higher mitochondrial density than that in non-differentiated cells. Additionally, 2H increased mitochondrial activity in both cell types as shown by their differentiation and lipid formation stages. Lupenone was isolated from 2H (Lu-CQ) and shown to dose-dependently inhibit adipogenesis, with 2H being more potent than Lu-CQ. Lu-CQ and 2H downregulated the expression of Pparg2 mRNA and upregulated that of glucose transporter genes, Slc2a1 and Slc2a4. Lu-CQ and 2H induced increased glucose uptake by 3T3-L1 cells. These findings suggest that lupenone-rich fractions in CQ contribute to balancing metabolic activity and reducing adipose tissue formation. Further exploration of CQ and its components may prompt innovative strategies for managing obesity and metabolic disorders.

Lupenone improves type 2 diabetic nephropathy by regulating NF-κB pathway-mediated inflammation and TGF-β1/Smad/CTGF-associated fibrosis

BACKGROUND

Type 2 diabetic nephropathy is a common diabetic complication and the main cause of death in patients with diabetes. Research has aimed to find an ideal drug with minimal side effects for treating this disease. Banana peel has been shown to be anti-diabetic, with lupenone isolated from banana peel exhibiting antidiabetic and anti-inflammatory activities; However, the effects of lupenone on type 2 diabetic nephropathy are largely unknown.

PURPOSE

This study aimed to investigate the ameliorative effect of lupenone on type 2 diabetic nephropathy, and its mechanism from both anti-inflammatory and anti-fibrotic perspectives.

METHODS

Spontaneous type 2 diabetic nephropathy db/db mouse models were given three levels of lupenone (24 or 12 or 6 mg/kg/d) via intragastric administration for six weeks, and irbesartan treatment was used for the positive control group. We explored the effects and mechanism of lupenone action using enzyme-linked immunosorbent assay, automatic biochemical analyzer, hematoxylin-eosin and Masson staining, real time-PCR, and western blotting. Concurrently, a high-sugar and high-fat diet combined with a low-dose streptozotocin-induced type 2 diabetic nephropathy rat model was used for confirmatory research.

RESULTS

Lupenone administration maintained the fasting blood glucose; reduced glycosylated hemoglobin, insulin, and 24 h proteinuria levels; and markedly regulated changes in biochemical indicators associated with kidney injury in serum and urine (including 24 h proteinuria, micro-albumin, N-acetyl-β-d-glucosaminidase, α1-micro-globulin, creatinine, urea nitrogen, uric acid, total protein, and albumin) of type 2 diabetic nephropathy mice and rats. Hematoxylin-eosin and Masson staining as well as molecular biology tests revealed that inflammation and fibrosis are the two key processes affected by lupenone treatment. Lupenone protected type 2 diabetic nephropathy kidneys by regulating the NF-κB-mediated inflammatory response and TGF-β1/Smad/CTGF pathway-associated fibrosis.

CONCLUSION

Lupenone has potential as an innovative drug for preventing and treating diabetic nephropathy. Additionally, it has great value for the utilization of banana peel resources.

Pharmacologically Active Phytomolecules Isolated from Traditional Antidiabetic Plants and Their Therapeutic Role for the Management of Diabetes Mellitus

Diabetes mellitus is a chronic complication that affects people of all ages. The increased prevalence of diabetes worldwide has led to the development of several synthetic drugs to tackle this health problem. Such drugs, although effective as antihyperglycemic agents, are accompanied by various side effects, costly, and inaccessible to the majority of people living in underdeveloped countries. Medicinal plants have been used traditionally throughout the ages to treat various ailments due to their availability and safe nature. Medicinal plants are a rich source of phytochemicals that possess several health benefits. As diabetes continues to become prevalent, health care practitioners are considering plant-based medicines as a potential source of antidiabetic drugs due to their high potency and fewer side effects. To better understand the mechanism of action of medicinal plants, their active phytoconstituents are being isolated and investigated thoroughly. In this review article, we have focused on pharmacologically active phytomolecules isolated from medicinal plants presenting antidiabetic activity and the role they play in the treatment and management of diabetes. These natural compounds may represent as good candidates for a novel therapeutic approach and/or effective and alternative therapies for diabetes.