Effects of Ginsenoside Rg3 on Inhibiting Differentiation, Adipogenesis, and ER Stress-Mediated Cell Death in Brown Adipocytes

Panax ginseng extract prevents UVB-induced skin photodamage by modulating VMP1-mediated ER stress

BACKGROUND

The endoplasmic reticulum (ER) stress is a crucial toxic signaling event triggered by chronic exposure to Ultraviolet B radiation (UVB), which significantly exacerbate photodamage responses in the irradiated skin. Therefore, the identification of agents capable of inhibiting ER stress could serve as a promising therapeutic strategy for addressing the unmet clinical needs in the treatment of UVB-induced photodamage.

METHODS

A UVB-irradiated mouse model was used and topical administration of Panax ginseng extract was carried out for a duration of 9 weeks. Vitamin E was used as a positive control. After 9 weeks of administration, the skin appearance, epidermal hyperplasia, infiltration of inflammatory cells, apoptosis, and collagen content were measured. The keratinocytes were irradiated with 6 mJ/cm2 UVB to establish an in vitro model. The levels of ER stress and apoptosis were investigated both in vivo and in vitro using qRT-PCR, immunoblotting, and immunofluorescence.

RESULTS

Among the 14 extracts derived from 13 distinct plant species that were screened, Panax ginseng, Prunus mume, and Camellia japonica showed inhibitory effect on UVB-induced ER stress. Notably, Panax ginseng effectively inhibits collagen degradation and apoptosis in both irradiated keratinocytes and Balb/C mice skin. Furthermore, the silencing of VMP1 significantly impeded the cellular protective effect of Panax ginseng extract on UVB-irradiated keratinocytes, indicating that Panax ginseng exerts its protective effects through targeted promotion of VMP1.

CONCLUSION

Our data suggest that Panax ginseng extract possess a therapeutical effect on UVB radiation-induced photodamage by promoting VMP1-mediated inhibition of ER stress.

Ginsenoside Rg3, enriched in red ginseng extract, improves lipopolysaccharides-induced suppression of brown and beige adipose thermogenesis with mitochondrial activation

Brown adipose tissue (BAT) which is a critical regulator of energy homeostasis, and its activity is inhibited by obesity and low-grade chronic inflammation. Ginsenoside Rg3, the primary constituent of Korean red ginseng (steamed Panax ginseng CA Meyer), has shown therapeutic potential in combating inflammatory and metabolic diseases. However, it remains unclear whether Rg3 can protect against the suppression of browning or activation of BAT induced by inflammation. In this study, we conducted a screening of ginsenoside composition in red ginseng extract (RGE) and explored the anti-adipogenic effects of both RGE and Rg3. We observed that RGE (exist 0.25 mg/mL of Rg3) exhibited significant lipid-lowering effects in adipocytes during adipogenesis. Moreover, treatment with Rg3 (60 μM) led to the inhibition of triglyceride accumulation, subsequently promoting enhanced fatty acid oxidation, as evidenced by the conversion of radiolabeled 3H-fatty acids into 3H-H2O with mitochondrial activation. Rg3 alleviated the attenuation of browning in lipopolysaccharide (LPS)-treated beige adipocytes and primary brown adipocytes by recovered by uncoupling protein 1 (UCP1) and the oxygen consumption rate compared to the LPS-treated group. These protective effects of Rg3 on inflammation-induced inhibition of beige and BAT-derived thermogenesis were confirmed in vivo by treating with CL316,243 (a beta-adrenergic receptor agonist) and LPS to induce browning and inflammation, respectively. Consistent with the in vitro data, treatment with Rg3 (2.5 mg/kg, 8 weeks) effectively reversed the LPS-induced inhibition of brown adipocyte features in C57BL/6 mice. Our findings confirm that Rg3-rich foods are potential browning agents that counteract chronic inflammation and metabolic complications.

Combination of Panax ginseng and Diospyros kaki Leaf Inhibits White Adipocyte Differentiation and Browning Process through AMP-Activated Protein Kinase (AMPK) Activation In Vitro and In Vivo

Activating brown adipose tissue (BAT) and stimulating white adipose tissue (WAT) browning is a prospective obesity treatment method. Dietary components derived from plants are the most effective approach to activate BAT and promote WAT browning in rodents. This study investigated the synergistic effects of Panax ginseng (PG) and Diospyros kaki leaf (DKL) extract on adipocyte differentiation and browning, as well as the molecular mechanism underlying their beneficial effects. The administration of PG and DKL to HFD-induced obese mice significantly decreased body weight and epididymal and abdominal adipose tissue mass. In in vitro, PG inhibited the adipogenesis of 3T3-L1 adipocytes by regulating the expression of key adipogenic regulators, such as peroxisome proliferator-activated receptor (PPAR)γ and CCAAT/enhancer-binding protein (C/EBP)-α. In contrast, DKL negligibly influenced the adipogenesis of 3T3-L1 adipocytes but greatly increased the protein expression of UCP-1, PGC-1α, and PPARα in BAT and/or WAT. Moreover, PG and DKL inhibited adipogenesis synergistically and activated white adipocyte browning via AMP-activated protein kinase (AMPK) and sirtuin 1 (SIRT1) pathways. These results suggest that a combination of PG and DKL regulates adipogenesis in white adipocytes and browning in brown adipocytes by activating AMPK/SIRT1 axis. The potential use of PG and DKL may represent an important strategy in obesity management that will be safer and more effective.

Micron and nano hybrid ufasomes from conjugated linoleic acid, their vesiculation and encapsulation of ginsenoside Rg3

BACKGROUND

Unsaturated fatty acids used to form unstable micro-vesicles, while conjugate linoleic acid (CLA)-sodium dodecyl sulfate (SDS) can self-assembly to stable nano-conjugate linoleic acid vesicles (nano-CLAVs). Generally, micro-capsule could geometrically provide higher loading capacity but also generate concerns in construction convenience, sustained release, bioaccessibility and stability. Hence there is a contradiction between loading capacity and encapsulation efficiency. Therefore, the study of the factors that decide the capsule size falling in nano or micron size with same capsule material would be a benefit to food or drug delivery science.

RESULTS

The micron- and nano-CLAVs were constructed for encapsulation and sustained release of ginsenoside Rg3. The formation mechanism of nano or micron capsule,s the effect of vesicle sizes on encapsulation efficiency, drug loading efficiency and stability of the encapsulated Rg3 were investigated. It was found that with the addition of salt (PBS), the size of CLAVs jumped from nano to micron. Furthermore, the salt concentration is the key factor that decides the vesicle size of nano or micron. The pH at fabrication triggers the vesiculation and dramatically affects the vesicle size over the nano and micron scales.

CONCLUSION

Compared to the nano-CLAVs, micron vesicles enhanced the loading capacity to 137.6% and the encapsulation efficiency to 138.4%, respectively. Meanwhile, the micron-CLAVs performed similar sustained release of Rg3 as the nano-CLAVs did, and was stable for 120 days at room temperature or sustained 98.9% of capsules after centrifuge at 6090 × g for 20 min. © 2022 Society of Chemical Industry.

Panax notoginseng extract and total saponin suppress diet-induced obesity and endoplasmic reticulum stress in epididymal white adipose tissue in mice

Background

Investigation on protective effects of Panax notoginseng against obesity and its related mechanisms is incomplete. Present study aimed to investigate the potential anti-obesity effect of the total saponins (PNS) and ethanolic extract of P. notoginseng (PNE).

Methods

Six-week-old male C57BL/6J mice received 45% kcal fat diet for 12 weeks to induce obesity. Oral administration of PNS and PNE at 20 mg/kg/day was applied for the last 4 weeks in the obese mice. Lipid profile was determined by ELISA. Histological examination was performed in liver and fat tissues. Protein levels were measured by Western blot.

Results

PNS and PNE did not cause weight loss. PNE but not PNS decreased the mass of epididymal and retroperitoneal white adipose tissue, accompanied by a reduction in adipocyte hypertrophy. PNS and PNE improved lipid profile by reducing the concentrations of triglyceride, total cholesterol and low-density lipoprotein cholesterol in plasma or liver samples. PNS and PNE also relieved fatty liver in obese mice. PNS and PNE inhibited expression and phosphorylation of endoplasmic reticulum (ER) stress-responsive proteins in hypertrophic adipose tissue.

Conclusions

PNS and PNE can regulate ER stress-mediated apoptosis and inflammation to alleviate obesity.