Detection of LPS-induced macrophage activation with single-cell resolution through DC insulator-based electrokinetic devices.

Macrophages are considered critical in the initiation, maintenance, and resolution of inflammation. Lipopolysaccharide (LPS)-induced inflammation is often used as a model to understand the cell inflammation responses. Current techniques identifying the LPS-induced inflammation are experiencing cell destruction or cell labeling or are based on the whole cell population information with low identification degree. This limits the detection process with time-consuming cytokine selection, low resolution of population heterogeneity, and unavailability for their next use. Direct current insulator-based electrokinetics (DC-iEK) is introduced to achieve an easier and noninvasive identification of inflamed cells with high resolution. A biophysical scale is also established first time for screening medicine in the treatment of inflammation. The new microfluidic design concentrates cells with applied voltages forming streamline providing more stable cell capture conditions and unique biophysical factors at different capture positions. The average electric field of the cell capture positions is recorded to characterize each cell population. The characterization value of macrophage decreases from to 1.61 × 104  V/m when treated with 0.1 mM LPS and to 1.42 × 104  V/m when treated with 1 mM LPS. By treating the inflamed macrophages with representative effective medicines, healing signals could also be detected by a newly established inflammation scale. The cells showed proliferation and functional activity after extraction. DC-iEK has provided an easy and noninvasive approach to identify inflammation for further fundamental and clinical precision medicine use.

Caffeic acid phenethyl ester suppresses intestinal FXR signaling and ameliorates nonalcoholic fatty liver disease by inhibiting bacterial bile salt hydrolase activity.

Propolis is commonly used in traditional Chinese medicine. Studies have demonstrated the therapeutic effects of propolis extracts and its major bioactive compound caffeic acid phenethyl ester (CAPE) on obesity and diabetes. Herein, CAPE was found to have pharmacological activity against nonalcoholic fatty liver disease (NAFLD) in diet-induced obese mice. CAPE, previously reported as an inhibitor of bacterial bile salt hydrolase (BSH), inhibited BSH enzymatic activity in the gut microbiota when administered to mice. Upon BSH inhibition by CAPE, levels of tauro-ß-muricholic acid were increased in the intestine and selectively suppressed intestinal farnesoid X receptor (FXR) signaling. This resulted in lowering of the ceramides in the intestine that resulted from increased diet-induced obesity. Elevated intestinal ceramides are transported to the liver where they promoted fat production. Lowering FXR signaling was also accompanied by increased GLP-1 secretion. In support of this pathway, the therapeutic effects of CAPE on NAFLD were absent in intestinal FXR-deficient mice, and supplementation of mice with C16-ceramide significantly exacerbated hepatic steatosis. Treatment of mice with an antibiotic cocktail to deplete BSH-producing bacteria also abrogated the therapeutic activity of CAPE against NAFLD. These findings demonstrate that CAPE ameliorates obesity-related steatosis at least partly through the gut microbiota-bile acid-FXR pathway via inhibiting bacterial BSH activity and suggests that propolis enriched with CAPE might serve as a promising therapeutic agent for the treatment of NAFLD.

Limosilactobacillus reuteri and caffeoylquinic acid synergistically promote adipose browning and ameliorate obesity-associated disorders.

OBJECTIVE: High intake of caffeoylquinic acid (CQA)-rich dietary supplements, such as green coffee bean extracts, offers health-promoting effects on maintaining metabolic homeostasis. Similar to many active herbal ingredients with high pharmacological activities but low bioavailability, CQA has been reported as a promising thermogenic agent with anti-obesity properties, which contrasts with its poor oral absorption. Intestinal tract is the first site of CQA exposure and gut microbes might react quickly to CQA. Thus, it is of interest to explore the role of gut microbiome and microbial metabolites in the beneficial effects of CQA on obesity-related disorders. RESULTS: Oral CQA supplementation effectively enhanced energy expenditure by activating browning of adipose and thus ameliorated obesity-related metabolic dysfunctions in high fat diet-induced obese (DIO) mice. Here, 16S rRNA gene amplicon sequencing revealed that CQA treatment remodeled the gut microbiota to promote its anti-obesity actions, as confirmed by antibiotic treatment and fecal microbiota transplantation. CQA enriched the gut commensal species Limosilactobacillus reuteri (L. reuteri) and stimulated the production of short-chain fatty acids, especially propionate. Mono-colonization of L. reuteri or low-dose CQA treatment did not reduce adiposity in DIO mice, while their combination elicited an enhanced thermogenic response, indicating the synergistic effects of CQA and L. reuteri on obesity. Exogenous propionate supplementation mimicked the anti-obesity effects of CQA alone or when combined with L. reuteri, which was ablated by the monocarboxylate transporter (MCT) inhibitor 7ACC1 or MCT1 disruption in inguinal white adipose tissues to block propionate transport. CONCLUSIONS: Our data demonstrate a functional axis among L. reuteri, propionate, and beige fat tissue in the anti-obesity action of CQA through the regulation of thermogenesis. These findings provide mechanistic insights into the therapeutic use of herbal ingredients with poor bioavailability via their interaction with the gut microbiota. Video Abstract.

Structural Characterization of a Polysaccharide from Gastrodia elata and Its Bioactivity on Gut Microbiota.

A novel homogeneous polysaccharide named GEP-1 was isolated and purified from Gastrodia elata (G. elata) by hot-water extraction, ethanol precipitation, and membrane separator. GEP-1, which has a molecular weight of 20.1 kDa, contains a polysaccharide framework comprised of only glucose. Methylation and NMR analysis showed that GEP-1 contained 1,3,6-linked-α-Glcp, 1,4-linked-α-Glcp, 1,4-linked-ß-Glcp and 1,4,6-linked-α-Glcp. Interestingly, GEP-1 contained citric acid and repeating p-hydroxybenzyl alcohol as one branch. Furthermore, a bioactivity test showed that GEP-1 could significantly promote the growth of Akkermansia muciniphila (A. muciniphila) and Lacticaseibacillus paracasei (L.paracasei) strains. These results implied that GEP-1 might be useful for human by modulating gut microbiota.

Structural characterization of two novel polysaccharides from Gastrodia elata and their effects on Akkermansia muciniphila.

Two homogeneous polysaccharides, GEP-3 and GEP-4, were purified from Gastrodia elata, a precious traditional Chinese medicine. Their structural characteristics were obtained using HPGPC, PMP-HPLC, LC/MS, FT-IR, NMR, and SEM methods. GEP-3 was 1,4-glucan with molecular weight of 20 kDa. Interestingly, GEP-4 comprised of a backbone of →[4)-α-Glcp-(1]10→[4)-α-Glcp-(1→]5[6)-ß-Glcp-(1]11→6)-α-Glcp-(3→ and two branches of ß-Glcp and p-hydroxybenzyl alcohol citrate, with repeating p-hydroxybenzyl alcohol attached to the backbone chain at O-6 position of →4,6)-α-Glcp-(1→ and O-1 position of →3,6)-α-Glcp-(1→. GEP-4 is a novel polysaccharide obtained and characterized for the first time. Bioactivity test indicated that both of them significantly promote the growth of Akkermansia muciniphila (Akk. muciniphila). Furthermore, GEP-3 and GEP-4 promoted the growth of Akk. muciniphila from high-fat diet (HFD) fecal microbiota. These results indicated that GEP-3 and GEP-4 were potential Akk. muciniphila growth promoters.

A novel 2-(2-Formyl-4-methyl-phenoxy)-N-phenyl-acetamide-based fluorescence turn-on chemosensor for selenium determination with high selectivity and sensitivity.

A novel turn-on fluorescent chemosensor, 2-(2-Formyl-4-methyl-phenoxy)-N-phenyl-acetamide (FMPPA) was designed and synthesized, and its photophysical properties were characterized. Upon coordination with Se (IV), the chemosensor showed incredible fluorescence enhancement (turn-on), other alkali, alkaline earth, transitional metal ions, and common anions including Li(+), Na(+), K(+), Rb(+), Cs(+), Be(2+), Mg(2+), Ca(2+), Sr(2+), Ba(2+), Ni(2+), Cu(2+), Cd(2+), Zn(2+), Mn(2+), As(3+), Pt(4+), V(5+), Fe(3+), Mo(6+), Al(3+), CO3(2-), Cl(-), SCN(-), AC(-), NO3(-), F(-), SO4(2-) had no significant interference on Se (IV) determination. The chemosensor exhibits a dynamic response range for Se (IV) from 3.32 × 10(-7) to 2.63 × 10(-6)M, with a detection limit of 9.38 × 10(-9)M (3σ).