Acankoreagenin and acankoreosides, a family of lupane triterpenoids with anti-inflammatory properties: an overview

Saponins of Selected Triterpenoids as Potential Therapeutic Agents: A Review

Saponins represent important natural derivatives of plant triterpenoids that are secondary plant metabolites. Saponins, also named glycoconjugates, are available both as natural and synthetic products. This review is focused on saponins of the oleanane, ursane, and lupane types of triterpenoids that include several plant triterpenoids displaying various important pharmacological effects. Additional convenient structural modifications of naturally-occurring plant products often result in enhancing the pharmacological effects of the parent natural structures. This is an important objective for all semisynthetic modifications of the reviewed plant products, and it is included in this review paper as well. The period covered by this review (2019–2022) is relatively short, mainly due to the existence of previously published review papers in recent years.

Multiple anti-non-alcoholic steatohepatitis (NASH) efficacies of isopropylidenyl anemosapogenin via farnesoid X receptor activation and TFEB-mediated autophagy

BACKGROUND

Non-alcoholic steatohepatitis (NASH) can develop into cirrhosis, liver failure, or hepatocellular carcinoma without effective treatment. However, there are currently no drugs for NASH treatment, and the development of new therapeutics has remained a major challenge in NASH research. Advances in traditional Chinese medicine to treat liver disease inspired us to search for new NASH candidates from Chi-Shao, a widely used traditional Chinese medicine.

PURPOSE

In this research, we aimed to clarify the anti-NASH effect and the underlying mechanism of isopropylidenyl anemosapogenin (IA, 1), which was a new lead compound isolated from Chi-Shao.

STUDY DESIGN AND METHODS

Isopropylidenyl anemosapogenin (IA, 1) was first discovered by collagen type I α 1 promoter luciferase bioassay-guided isolation and then characterized by single crystal X-ray diffraction analysis and enriched by semi-synthesis. Using various molecular biology techniques, the multiple anti-NASH efficacies and mechanisms of IA were clarified based on in vitro LX-2 and Huh7 cell models, along with the in vivo choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD)-induced mouse model and bile duct ligation (BDL)-induced rat model. The UPLC-MS/MS method was used to assess the plasma concentration of IA.

RESULTS

A new lead compound IA was isolated from the traditional Chinese medicine Chi-Shao, which showed significant anti-liver fibrosis activity in TGF-β1-treated LX-2 cells and anti-liver steatosis activity in oleic acid-treated Huh7 cells. Furthermore, IA could significantly ameliorate in vivo CDAHFD-induced liver injury by activating the farnesoid X receptor pathway, including its targets Nr0b2, Abcb11, and Slc10a2. Simultaneously, IA activated the autophagy pathway by activating the TFEB factor, thereby promoting lipid degradation. Its liver-protective and anti-fibrosis activities were verified by the BDL-induced rat model. Finally, with an oral administration of 100 mg/kg, IA achieved the maximum plasma concentration of 1.23 ± 0.18 μg/ml at 2.67 ± 0.58 h.

CONCLUSION

IA, an unreported lupine-type triterpenoid isolated from Chi-shao, can significantly alleviate liver injury and fibrosis via farnesoid X receptor activation and TFEB-mediated autophagy, which indicates that IA could serve as a novel therapeutic candidate against NASH.

Betulinic acid accelerates diabetic wound healing by modulating hyperglycemia-induced oxidative stress, inflammation and glucose intolerance

BACKGROUND

Diabetes significantly delays wound healing through oxidative stress, inflammation and impaired re-epithelialization that lead to defective regulation of the healing process, although the related mechanism remains unclear. Here, we aim to investigate the potential role and mechanism for the beneficial effect of betulinic acid (BA) on diabetic wound healing.

METHODS

The molecular effect of BA on hyperglycemia-mediated gene expression, oxidative stress, inflammation and glucose uptake was evaluated in endothelial, fibroblast and muscle cells. Burn injury was introduced to streptozotocin-induced diabetic rats and BA administration through either an intraperitoneal (IP) or topical (TOP) technique was used for wound treatment. Glucose tolerance was evaluated in both muscle tissue and fibroblasts, while oxidative stress and inflammation were determined in both the circulatory system and in wound tissues. The effect of BA on the wound healing process was also evaluated.

RESULTS

BA treatment reversed hyperglycemia-induced glucose transporter type 4 (GLUT4) suppression in both muscle and fibroblast cells. This treatment also partly reversed hyperglycemia-mediated suppression of endothelial nitric oxide synthase (eNOS), nuclear factor erythroid 2-related factor 2 (Nrf2) signaling and nuclear factor NFκB p65 subunit (NFκB p65) activation in endothelial cells. An in vivo rat study showed that BA administration ameliorated diabetes-mediated glucose intolerance and partly attenuated diabetes-mediated oxidative stress and inflammation in both the circulatory system and wound tissues. BA administration by both IP and TOP techniques significantly accelerated diabetic wound healing, while BA administration by either IP or TOP methods alone had a significantly lower effect.

CONCLUSIONS

BA treatment ameliorates hyperglycemia-mediated glucose intolerance, endothelial dysfunction, oxidative stress and inflammation. Administration of BA by both IP and TOP techniques was found to significantly accelerate diabetic wound healing, indicating that BA could be a potential therapeutic candidate for diabetic wound healing.