Effects of the Cistanche tubulosa Aqueous Extract on the Gut Microbiota of Mice with Intestinal Disorders

Echinacoside inhibits colorectal cancer metastasis via modulating the gut microbiota and suppressing the PI3K/AKT signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Echinacoside (ECH) is the dominant phenylethanoid glycoside-structured compound identified from our developed herbal formula Huangci granule, which has been previously reported to inhibit the invasion and metastasis of CRC and prolong patients' disease-free survival duration. Though ECH has inhibitory activity against aggressive colorectal cancer (CRC) cells, its anti-metastasis effect in vivo and the action mechanism is undetermined. Given that ECH has an extremely low bioavailability and gut microbiota drives the CRC progression, we hypothesized that ECH could inhibit metastatic CRC by targeting the gut microbiome.

AIM OF THE STUDY

The purpose of this study was to investigate the impact of ECH on colorectal cancer liver metastasis in vivo and its potential mechanisms.

MATERIALS AND METHODS

An intrasplenic injection-induced liver metastatic model was established to examine the efficiency of ECH on tumor metastasis in vivo. Fecal microbiota from the model group and the ECH group were separately transplanted into pseudo-sterile CRLM mice in order to verify the role of gut flora in the ECH anti-metastatic effect. The 16S rRNA gene sequence was applied to analyze the structure and composition of the gut microbiota after ECH intervention, and the effect of ECH on short-chain fatty acid (SCFAs)-producing bacteria growth was proven by anaerobic culturing in vitro. GC-MS was applied to quantitatively analyze the serum SCFAs levels in mice. RNA-seq was performed to detect the gene changes involving tumor-promoting signaling pathway.

RESULTS

ECH inhibited CRC metastasis in a dose-dependent manner in the metastatic colorectal cancer (mCRC) mouse model. Manipulation of gut bacteria in the mCRC mouse model further proved that SCFA-generating gut bacteria played an indispensable role in mediating the antimetastatic action of ECH. Under an anaerobic condition, ECH benefited SCFA-producing microbiota without affecting the total bacterial load, presenting a dose-dependent promotion on the growth of a butyrate producer, Faecalibacterium prausnitzii (F.p). Furthermore, ECH-reshaped or F.p-colonized microbiota with a high butyrate-producing capability inhibited liver metastasis by suppressing PI3K/AKT signaling and reversing the epithelial-mesenchymal transition (EMT) process, whereas this anti-metastatic ability was abrogated by the butyrate synthase inhibitor heptanoyl-CoA.

CONCLUSION

This study demonstrated that ECH exhibits oral anti-metastatic efficacy by facilitating butyrate-producing gut bacteria, which downregulates PI3K/AKT signaling and EMT. It hints at a novel role for ECH in CRC therapy.

Rapid Determination of Polysaccharides in Cistanche Tubulosa Using Near-Infrared Spectroscopy Combined with Machine Learning

BACKGROUND

Cistanche tubulosa, as a homology of medicine and food, not only has a unique medicinal value but also is widely used in healthcare products. Polysaccharide is one of its important quality indicators.

OBJECTIVE

In this study, an analytical model based on near-infrared (NIR) spectroscopy combined with machine learning was established to predict the polysaccharide content of C. tubulosa.

METHODS

The polysaccharide content in the samples determined by the phenol-sulfuric acid method was used as a reference value, and machine learning was applied to relate the spectral information to the reference value. Dividing the samples into a calibration set and a prediction set using the Kennard-Stone algorithm. The model was optimized by various preprocessing methods, including Savitzky-Golay (SG), standard normal variate (SNV), multiple scattering correction (MSC), first-order derivative (FD), second-order derivative (SD), and combinations of them. Variable selection was performed through the successive projections algorithm (SPA) and stability competitive adaptive reweighted sampling (sCARS). Four machine learning models were used to build quantitative models, including the random forest (RF), partial least-squares (PLS), principal component regression (PCR), and support vector machine (SVM). The evaluation indexes of the model were the coefficient of determination (R2), root-mean-square error (RMSE), and residual prediction deviation (RPD).

RESULTS

RF performs best among the four machine learning models. R2c （calibration set coefficient of determination） and RMSEC （root mean square error of the calibration set）, %, were 0.9763. and 0.3527 for calibration, respectively. R2p （prediction set coefficient of determination）, RMSEP （root mean square error of the prediction set）, %, and RPD were 0.9230, 0.5130, and 3.33 for prediction, respectively.

CONCLUSION

The results indicate that NIR combined with the RF is an effective method applied to the quality evaluation of the polysaccharides of C. tubulosa.

HIGHLIGHTS

Four quantitative models were developed to predict the polysaccharide content in C. tubulosa, and good results were obtained. The characteristic variables were basically determined by the sCARS algorithm, and the corresponding characteristic groups were analyzed.

Dietary Supplementation of Caulerpa racemosa Ameliorates Cardiometabolic Syndrome via Regulation of PRMT-1/DDAH/ADMA Pathway and Gut Microbiome in Mice

This study evaluated the effects of an aqueous extract of Caulerpa racemosa (AEC) on cardiometabolic syndrome markers, and the modulation of the gut microbiome in mice administered a cholesterol- and fat-enriched diet (CFED). Four groups of mice received different treatments: normal diet, CFED, and CFED added with AEC extract at 65 and 130 mg/kg body weight (BW). The effective concentration (EC₅₀) values of AEC for 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and lipase inhibition were lower than those of the controls in vitro. In the mice model, the administration of high-dose AEC showed improved lipid and blood glucose profiles and a reduction in endothelial dysfunction markers (PRMT-1 and ADMA). Furthermore, a correlation between specific gut microbiomes and biomarkers associated with cardiometabolic diseases was also observed. In vitro studies highlighted the antioxidant properties of AEC, while in vivo data demonstrated that AEC plays a role in the management of cardiometabolic syndrome via regulation of oxidative stress, inflammation, endothelial function (PRMT-1/DDAH/ADMA pathway), and gut microbiota.

Development of Cistanche deserticola Fermented Juice and Its Repair Effect on Ethanol-Induced WRL68 Cell Damage

Cistanche deserticola is a valuable Chinese herb, but traditional dry processing causes the loss of active substances. This study developed Cistanche deserticola fermented juice (CFJ) using lactic acid bacteria and optimized the fermentation process to achieve the maximum active substance content and taste. More interestingly, superoxide dismutase (SOD) activity was increased during fermentation, and CFJ exerted a reparative effect on ethanol-induced cell damage. SOD activity reached 603.26 U/mL when the ratios in the total inoculum volume of Lactobacillus reuteri, Lactococcus pentosus, Streptococcus thermophilus, Bifidobacterium animalis, Lactobacillus casei, and Lactobacillus acidophilus were 31.74%, 15.71%, 17.45%, 11.65%, 9.56%, and 13.89%, respectively. Further, the optimal fermentation conditions for CFJ were determined using a response surface methodology. More importantly, CFJ promoted the proliferation of WRL68 cells, and CFJ exerted an obvious reparative effect on ethanol-treated cells, in which the cell survival rate increased to 120.35 ± 0.77% (p < 0.05). The underlying mechanism might have been that CFJ reduced the MDA content in damaged cells from 1.36 nmol/mg prot to 0.88 nmol/mg prot and increased GSH-Px and SOD activities by 48% and 72%, respectively. This study provides a theoretical basis and reference data for the fermentation of C. deserticola and its hepatoprotective activity.