Anti-obesity effect of total phenylpropanoid glycosides from Ligustrum robustum Blume in fatty diet-fed mice via up-regulating leptin

Traditional Chinese medicine and plant-derived natural products in regulating triglyceride metabolism: Mechanisms and therapeutic potential

The incidence of cardiometabolic disease is increasing globally, with a trend toward younger age of onset. Among these, atherosclerotic cardiovascular disease is a leading cause of mortality worldwide. Despite the efficacy of traditional lipid-lowering drugs, such as statins, in reducing low-density lipoprotein cholesterol levels, a significant residual risk of cardiovascular events remains, which is closely related to unmet triglyceride (TG) targets. The clinical application of current TG-lowering Western medicines has certain limitations, necessitating alternative or complementary therapeutic strategies. Traditional Chinese medicine (TCM) and plant-derived natural products, known for their safety owing to their natural origins and diverse biological activities, offer promising avenues for TG regulation with potentially fewer side effects. This review systematically summarises the mechanisms of TG metabolism and subsequently reviews the regulatory effects of TCM and plant-derived natural products on TG metabolism, including the inhibition of TG synthesis (via endogenous and exogenous pathways), promotion of TG catabolism, regulation of fatty acid absorption and transport, enhancement of lipophagy, modulation of the gut microbiota, and other mechanisms. In conclusion, through a comprehensive analysis of recent studies, this review consolidates the multifaceted regulatory roles of TCM and plant-derived natural products in TG metabolism and elucidates their potential as safer, multi-target therapeutic agents in managing hypertriglyceridemia and mitigating cardiovascular risk, thereby providing a basis for new drug development.

Potential of polyphenols from Ligustrum robustum (Rxob.) Blume on enhancing the quality of starchy food during frying

The increasing concerns about health have led to a growing demand for high-quality fried foods. The potential uses of Ligustrum robustum (Rxob.) Blume, a traditional tea in China, as natural additives to enhance the quality of starchy food during frying was studied. Results indicated that L. robustum polyphenols extract (LREs) could improve the quality of fried starchy food, according to the tests of color, moisture content, oil content, texture property, and volatile flavor. The in vitro digestion results demonstrated that LRE reduced the final glucose content from 11.35 ± 0.17 to 10.80 ± 0.70 mmol/L and increased the phenolic content of fried starch foods from 1.23 ± 0.04 to 3.76 ± 0.14 mg/g. The appearance and polarizing microscopy results showed that LRE promoted large starch bulges on the surface of fried starchy foods. Meanwhile, X-ray diffraction results showed that LRE increased the intensity of characteristic diffraction peak of fried starch with a range of 21.8%-28%, and Fourier transform infrared results showed that LRE reduced the damage to short-range order structure of starch caused by the frying process. In addition, LRE increased the aggregation of starch granules according to the SEM observation and decreased the enthalpy of starch gelatinization based on the differential scanning calorimetry results. The present results suggest that LREs have the potential to be utilized as a natural additive for regulating the quality of fried starchy food in food industries. PRACTICAL APPLICATION: The enhancement of L. robustum polyphenols on the quality of starchy food during frying was found, and its mechanisms were also explored. This work indicated that L. robustum might be used as a novel economic natural additive for producing high-quality fried foods.

A New HPLC-UV Method Using Hydrolyzation with Sodium Hydroxide for Quantitation of Trans-p-Hydroxycinnamic Acid and Total Trans-p-Hydroxycinnamic Acid Esters in the Leaves of Ligustrum robustum

Trans-p-hydroxycinnamic acid and its esters in the leaves of Ligustrum robustum might be a new resource to prevent diabetes and its complications. In the present study, a new HPLC-UV method using hydrolyzation with sodium hydroxide for quantitation of trans-p-hydroxycinnamic acid and total trans-p-hydroxycinnamic acid esters in the leaves of L. robustum was developed, since it was difficult and troublesome to analyze no less than 34 trans-p-hydroxycinnamic acid esters by usual HPLC. The extract of L. robustum was hydrolyzed with sodium hydroxide at 80 °C for 2 h, and then, hydrochloride was added. HPLC analysis was performed in reverse phase mode using a C-18 column, eluting with methanol-0.1% acetic acid aqueous solution (40:60, v/v) in isocratic mode at a flow rate of 1.0 mL·min^-1 and detecting at 310 nm. The linear range for trans-p-hydroxycinnamic acid was 11.0-352.0 μg·mL^-1 (r² = 1.000). The limit of detection and limit of quantification were 2.00 and 6.07 μg·mL^-1, respectively. The relative standard deviations of intra-day and inter-day variabilities for trans-p-hydroxycinnamic acid were less than 2%. The percentage recovery of trans-p-hydroxycinnamic acid was 103.3% ± 1.1%. It is the first HPLC method using hydrolyzation for quantification of many carboxylic esters. Finally, the method was used successfully to determine trans-p-hydroxycinnamic acid and total trans-p-hydroxycinnamic acid esters in various extracts of the leaves of L. robustum. The 60-70% ethanol extracts of L. robustum showed the highest contents of free trans-p-hydroxycinnamic acid (3.96-3.99 mg·g^-1), and the 50-80% ethanol extracts of L. robustum displayed the highest contents of total trans-p-hydroxycinnamic acid esters (202.6-210.6 mg·g^-1). The method can be applied also to the quality control of the products of L. robustum.

Chemical Constituents from the Leaves of Ligustrum robustum and Their Bioactivities

The leaves of Ligustrum robustum have been consumed as Ku-Ding-Cha for clearing heat and removing toxins, and they have been used as a folk medicine for curing hypertension, diabetes, and obesity in China. The phytochemical research on the leaves of L. robustum led to the isolation and identification of two new hexenol glycosides, two new butenol glycosides, and five new sugar esters, named ligurobustosides X (1a), X₁ (1b), Y (2a), and Y₁ (2b) and ligurobustates A (3a), B (3b), C (4b), D (5a), and E (5b), along with seven known compounds (4a and 6-10). Compounds 1-10 were tested for their inhibitory effects on fatty acid synthase (FAS), α-glucosidase, and α-amylase, as well as their antioxidant activities. Compound 2 showed strong FAS inhibitory activity (IC₅₀ 4.10 ± 0.12 μM) close to that of the positive control orlistat (IC₅₀ 4.46 ± 0.13 μM); compounds 7 and 9 revealed moderate α-glucosidase inhibitory activities; compounds 1-10 showed moderate α-amylase inhibitory activities; and compounds 1 and 10 displayed stronger 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) ammonium salt (ABTS) radical scavenging effects (IC₅₀ 3.41 ± 0.08~5.65 ± 0.19 μM) than the positive control l-(+)-ascorbic acid (IC₅₀ 10.06 ± 0.19 μM). This study provides a theoretical foundation for the leaves of L. robustum as a functional tea to prevent diabetes and its complications.

Phenylethanoid and Phenylmethanoid Glycosides from the Leaves of Ligustrum robustum and Their Bioactivities

The phytochemical study on the leaves of Ligustrum robustum, which have been used as Ku-Ding-Cha, led to the isolation and identification of three new phenylethanoid glycosides and three new phenylmethanoid glycosides, named ligurobustosides R₁ (1b), R_2-3 (2), R₄ (3), S₁ (4b), S₂ (5), and S₃ (6), and five reported phenylethanoid glycosides (7-11). In the bioactivity test, (Z)-osmanthuside B₆ (11) displayed strong fatty acid synthase (FAS) inhibitory activity (IC₅₀: 4.55 ± 0.35 μM) as the positive control orlistat (IC₅₀: 4.46 ± 0.13 μM), while ligurobustosides R₄ (3) and S₂ (5), ligupurpuroside B (7), cis-ligupurpuroside B (8), ligurobustoside N (9), osmanthuside D (10), and (Z)-osmanthuside B₆ (11) showed stronger ABTS radical scavenging activity (IC₅₀: 2.68 ± 0.05~4.86 ± 0.06 μM) than the positive control L-(+)-ascorbic acid (IC₅₀: 10.06 ± 0.19 μM). This research provided a theoretical basis for the leaves of L. robustum as a tea with function in treating obesity and diabetes.

Monoterpenoid Glycosides from the Leaves of Ligustrum robustum and Their Bioactivities

The leaves of Ligustrum robustum have been applied as Ku-Ding-Cha, a functional tea to clear heat, remove toxins, and treat obesity and diabetes, in Southwest China. The phytochemical research on the leaves of L. robustum led to the isolation and identification of eight new monoterpenoid glycosides (1–8) and three known monoterpenoid glycosides (9–11). Compounds 1–11 were tested for the inhibitory activities on fatty acid synthase (FAS), α-glucosidase, α-amylase, and the antioxidant effects. Compound 2 showed stronger FAS inhibitory activity (IC₅₀: 2.36 ± 0.10 μM) than the positive control orlistat (IC₅₀: 4.46 ± 0.13 μM), while compounds 1, 2, 5 and 11 displayed more potent ABTS radical scavenging activity (IC₅₀: 6.91 ± 0.10~9.41 ± 0.22 μM) than the positive control L-(+)-ascorbic acid (IC₅₀: 10.06 ± 0.19 μM). This study provided a theoretical basis for the leaves of L. robustum as a functional tea to treat obesity.

Neohesperidin Dihydrochalcone and Neohesperidin Dihydrochalcone-O-Glycoside Attenuate Subcutaneous Fat and Lipid Accumulation by Regulating PI3K/AKT/mTOR Pathway In Vivo and In Vitro

Neohesperidin dihydrochalcone (NHDC), a semi-natural compound from bitter orange, is an intense sweetener. The anti-obesity effects of NHDC and its glycosidic compound, NHDC-O-glycoside (GNHDC), were investigated. C57BLKS/J db/db mice were supplemented with NHDC or GNHDC (100 mg/kg b.w.) for 4 weeks. Body weight gain, subcutaneous tissues, and total adipose tissues (sum of perirenal, visceral, epididymal, and subcutaneous adipose tissue) were decreased in the NHDC and GNHDC groups. Fatty acid uptake, lipogenesis, and adipogenesis-related genes were decreased, whereas β-oxidation and fat browning-related genes were up-regulated in the sweetener groups. Furthermore, both sweeteners suppressed the level of triacylglycerol accumulation, lipogenesis, adipogenesis, and proinflammatory cytokines in the 3T3-L1 cells. The PI3K/AKT/mTOR pathway was also down-regulated, and AMP-acttvated protein kinase (AMPK) was phosphorylated in the treatment groups. These results suggest that NHDC and GNHDC inhibited subcutaneous fat and lipid accumulation by regulating the PI3K/AKT/mTOR pathway and AMPK-related lipogenesis and fat browning.

Natural Dietary and Medicinal Plants with Anti-Obesity Therapeutics Activities for Treatment and Prevention of Obesity during Lock Down and in Post-COVID-19 Era

Overweight and obesity have become global epidemics, especially during the lockdown due to the COVID-19 pandemic. The potential of medicinal plants as a better and safe option in treating obesity and overweight has gained attention in recent years. Obesity and overweight has become a major public health concern, and its incidence rising at an alarming rate. Obesity is one of the major types of metabolic syndrome, resulting in various types of problems such as hypertension, diabetes, dyslipidemia, and excess fat accumulation. The current searching was done by the keywords in main indexing systems including Scopus, PubMed/MEDLINE, the search engine of Google Scholar, and Institute for Scientific Web of Science. The keywords were traditional medicine, health benefits, pharmaceutical science, pomegranate, punicalin, punicalagin, and ellagitannins. Google Scholar was searched manually for possible missing manuscripts, and there was no language restriction in the search. This review was carried out to highlight the importance of medicinal plants which are common in traditional medicinal sciences of different countries, especially Asia to prevent and treatment of obesity and overweight during the global pandemic and the post-COVID-19 era.

Ligustrum robustum Alleviates Atherosclerosis by Decreasing Serum TMAO, Modulating Gut Microbiota, and Decreasing Bile Acid and Cholesterol Absorption in Mice

SCOPE

Atherosclerosis (AS) is closely related to gut microbiota. Previous studies demonstrates that Ligustrum robustum (LR), a flavonoid-rich tea like plant, can mitigate several AS-related risk factors and modulate gut microbiota in animal models and human subjects. But its anti-AS effect and mechanisms remain unclear. Therefore, in this study, impacts of LR on AS development are investigated and the potential underlying mechanisms in C57BL/6J and Apoe^-/- mice are explored.

METHODS AND RESULTS

Female C57BL/6J and Apoe^{-/ -} mice are fed a chow diet or high-choline diet, supplemented with vehicle (water) or LR water extract (700 mg kg^-1 ) by gavage for 17 weeks. It is found that LR attenuates diet-induced AS by reducing serum trimethylamine and trimethylamine-N-oxide (TMAO) levels likely by modulating gut microbiota. Moreover, LR increases the abundance of the genus Bifidobacterium, which generates bile salt hydrolase, and thus presumably enhances bile acid (BA) deconjugation and increases fecal BA excretion. Meanwhile, LR increases fecal cholesterol excretion, decreases the levels of serum and hepatic cholesterol, but did not affect short-chain fatty acids in feces.

CONCLUSION

LR attenuates AS development presumably by decreasing serum TMAO levels and increasing fecal BA excretion likely via gut microbial modulation. These effects are accompanied by increases in fecal cholesterol excretion and decreases in serum and hepatic cholesterol.

Effects of Lippia citriodora Leaf Extract on Lipid and Oxidative Blood Profile of Volunteers with Hypercholesterolemia: A Preliminary Study

Lippia citriodora is a plant traditionally used for its anti-inflammatory, antioxidant and antispasmodic effects, as well as for additional biological activities proven in cell culture, animal studies and a small number of human clinical trials. The plant has also shown a marked improvement in blood lipid profile in some animal species. In the present preliminary study, we investigated the effect of a leaf extract on lipid and oxidative blood profile of hypercholesterolemic volunteers. Twelve adults received Lippia citriodora extract caps, containing 23% phenylpropanoids, (100 mg, once a day) for 16 weeks. Selected blood lipids and plasma oxidative markers were measured at baseline and after 4, 8 and 16 weeks of treatment. Compared with baseline, total cholesterol levels significantly decreased and high-density lipoprotein cholesterol increased, while low-density lipoprotein cholesterol and triglycerides showed only a downward trend. Oxidative status was improved due to a decrease in the concentration of total oxidant status, reactive oxygen metabolites and malondialdehyde, and a significant increase in ferric reducing ability of plasma, vitamin A and vitamin E. These preliminary results suggest that dietary supplementation with Lippia citriodora extract can improve the lipid profile, enhance blood antioxidant power, and could be a valuable natural compound for the management of human hypercholesterolemia.

Ligustrum robustum (Roxb.) blume extract modulates gut microbiota and prevents metabolic syndrome in high-fat diet-fed mice

ETHNOPHARMACOLOGICAL RELEVANCE

In Chinese folk medicine, Ligustrum robustum (Roxb.) Blume has been widely used as a healthy tea beverage for improvement in obesity and lipidemic metabolic disorders.

AIM OF THE STUDY

We aimed to investigate the effect of L. robustum extract (LRE) on metabolic syndrome in high-fat diet (HFD)-fed mice and to explore the underlying role of gut microbiota during the treatment.

MATERIALS AND METHODS

The ground dried leaves of L. robustum (Roxb.) Blume were extracted with ethanol and then purified by a resin column. The composition of L. robustum extract (LRE) was analyzed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). C57BL/6 J mice fed with HFD were treated with LRE for 16 weeks. RT-qPCR and morphological staining were utilized to reveal the impact of LRE on hepatic glucolipid metabolism and gut integrity. The next-generation sequencing of 16 S rDNA was applied for analyzing the gut microbial community of fecal samples.

RESULTS

LRE, mainly composed of ligupurpuroside A and aceteoside, alleviated insulin resistance, improved hepatic metabolism, enhanced intestinal integrity, and suppressed inflammatory responses in HFD-fed mice. Moreover, LRE treatment reshaped the gut microbiota structure by increasing the levels of genera Streptococcus, Lactobacillus, and Mucispirillum and decreasing the populations of Alistipes and Lachnospiraceae NK4A136 group in HFD-fed mice. The alteration of gut microbiota was associated with several metabolic pathways of gut bacteria. Spearman's correlation analysis further confirmed the links between the changed intestinal bacteria and multiple disease indices.

CONCLUSIONS

LRE prevented gut microbiota dysbiosis and metabolic disorder in HFD-fed mice, which helps to promote the application in LRE-mediated prevention from metabolic syndrome as a gut microbial regulator.

The effect of Plantago major supplementation on leptin and VEGF-A serum levels, endothelial dysfunction and angiogenesis in obese women - a randomised trial

Obesity is associated with increased serum leptin level, endothelial dysfunction and angiogenesis. In vitro studies have shown that vascular endothelial growth factor (VEGF) synthesis is increased by leptin. Animal studies revealed the effectiveness of Plantago supplementation treatment of obesity. The study aim was to evaluate the effect of Plantago major supplementation on serum leptin and VEGF blood concentration, endothelial dysfunction and angiogenesis in obese women. Seventy-two obese women received oral Plantago major supplement (Plantago group, n = 35) or placebo (placebo group, n = 37) for 12 weeks. At baseline and after completion, anthropometric and body composition measurements were performed, and blood samples were collected. Serum concentrations of leptin, VEGF-A, adiponectin, tumour necrosis factor α and soluble intercellular adhesion molecule have been determined. At completion, the leptin level was higher in the Plantago group (39 781.55 ± 20 360.73 pg ml-1) compared to both the baseline (36 138.71 ± 25 401.51 pg ml-1) and placebo group (30 502.81 ± 19 003.18 pg ml-1). Also, leptin concentration in the Plantago group at completion correlated positively with an increase in VEGF-A level (R = 0.45), and baseline VEGF-A level correlated negatively with the increase in leptin concentration (R = -0.47). Plantago major supplementation increases leptin serum level, enhances leptin influence on VEGF-A serum level increase and by this mechanism may intensify endothelial dysfunction and angiogenesis in obese women.

Comparison of main chemical composition of Plantago asiatica L. and P. depressa Willd. seed extracts and their anti-obesity effects in high-fat diet-induced obese mice

BACKGROUND

Nowadays, the pharmacological effects of Plantaginis semen was getting more and more attention because of the great effect of treating diuresis, hypertension, hyperlipidemia, and hyperglycemia. According to the Chinese Pharmacopoeia, Plantaginis semen is the seed of Plantago asiatica L. or P. depressa Willd. This was verified by examining chemical composition differences in a preliminary experiment, predicting their differences in pharmacology.

PURPOSE

In this study, we aimed to compared the the differences in main components and anti-obesity effects of Plantago asiatica L. seed extract (PASE) and P. depressa Willd. seed extract (PDSE).

STUDY DESIGN AND METHODS

The ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) analysis was used to characterize and compare the differences chemical constituents of PASE and PDSE. The difference therapeutic effects between PASE and PDSE on obesity and associated metabolic disorders was investigated by high-fat (HF) diet induced mice model.

RESULTS

The fingerprint of Plantaginis semen were established by screening and identified 15 main components, including iridoids, phenethanol glycosides, flavonoids, guanidines, and fatty acids. Pentahydroxy flavanone was observed only in PDSE but not in PASE. The quantitative analysis results indicated that the main bioactive components in PASE were geniposidic acid and acteoside; their concentrations were three times higher in PASE than in PDSE. In anti-obesity effects, the result show the levels of fasting blood glucose were improved in both PASE and PDSE when compared with the HF group, while the PASE is show a significant effect then the PDSE group and improved the glucose tolerance but not in PDSE. The results also displayed that the Plantaginis semen did not modify food intake or body weight but decreased abdominal white/brown adipocyte size, serum total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-c), hepatic TG and TC, fecal TG and TC concentrations when compared with the HF group. Among these indicators, serum TG, liver TG, fecal TC and TG levels were significantly improved in PASE compared with PDSE. The results indicated that PASE treatment more effectively improved lipid and glucose metabolism in HF diet-induced obese mice than did PDSE.

CONCLUSION

As Plantaginis semen sources, P. asiatica L. seeds demonstrated more bioactive components and favorable metabolic disorder treatment outcomes than did P. depressa Willd. seeds.

Activity of Ligustrum robustum (Roxb.) Blume extract against the biofilm formation and exopolysaccharide synthesis of Streptococcus mutans

Ligustrum robustum (Roxb.) Blume is utilized as a traditional Chinese herbal tea with various health benefits and protective effects. Streptococcus mutans is an important cariogenic oral bacteria species. The present study aimed to assess the influence of Ligustrum robustum extract (LRE) on the biofilm formation of S. mutans and the mechanism of its action, as well as to identify its chemical components. For chemical identification, HPLC-MS and nuclear magnetic resonance were applied and four identified phytochemicals were reported (Ligurobustoside B, Ligurobustoside N, Ligurobustoside J, and Ligurobustoside C). The dose-dependent (0.5 to 2.0 μg/μL) antimicrobial toxicity of LRE against S. mutans biofilm formation and exopolysaccharide (EPS) synthesis was evaluated by confocal laser scanning microscopy (CLSM), Crystal violet stain, and CFU counting. The microstructure of S. mutans biofilm treated with LRE was investigated both on glass coverslips and ex vivo bovine dental enamel by scanning electron microscopy (SEM). Moreover, LRE downregulated the expression of S. mutans glucosyltransferase-encoding genes gtfB, gtfC, and gtfD, and the quorum sensing (QS) factors comD and comE, suggesting its toxic mechanism. In addition, the result of CCK-8 test on human oral cells revealed an acceptable biocompatibility of LRE. These findings indicated the possible application of this daily consumed herbal tea for caries prevention.

Therapeutic potential of phenylethanoid glycosides: A systematic review

Phenylethanoid glycosides (PhGs) are generally water-soluble phenolic compounds that occur in many medicinal plants. Until June 2020, more than 572 PhGs have been isolated and identified. PhGs possess antibacterial, anticancer, antidiabetic, anti-inflammatory, antiobesity, antioxidant, antiviral, and neuroprotective properties. Despite these promising benefits, PhGs have failed to fulfill their therapeutic applications due to their poor bioavailability. The attempts to understand their metabolic pathways to improve their bioavailability are investigated. In this review article, we will first summarize the number of PhGs compounds which is not accurate in the literature. The latest information on the biological activities, structure-activity relationships, mechanisms, and especially the clinical applications of PhGs will be reviewed. The bioavailability of PhGs will be summarized and factors leading to the low bioavailability will be analyzed. Recent advances in methods such as bioenhancers and nanotechnology to improve the bioavailability of PhGs are also summarized. The existing scientific gaps of PhGs in knowledge are also discussed, highlighting research directions in the future.

Preventive effect of small-leaved Kuding tea (Ligustrum robustum) on high-diet-induced obesity in C57BL/6J mice

Small-leaved Kuding tea (SLKDT; Ligustrum robustum) is a traditional Chinese tea. We systematically investigated the effect of SLKDT extract on obesity. SLKDT-controlled weight gain in mice fed a high-fat diet. Tissue specimen results showed that the SLKDT extract alleviated liver damage and fat accumulation. Meanwhile, SLKDT extract improved dyslipidemia by decreasing total cholesterol, triglycerides, and low-density lipoprotein cholesterol levels and increasing high-density lipoprotein cholesterol levels. Furthermore, SLKDT extract reduced alanine aminotransferase, alkaline phosphatase, and aspartate transaminase levels in the serum and liver tissues; decreased inflammatory cytokines, including interleukin (IL)-1β, tumor necrosis factor-α, interferon-γ, and IL-6; and increased the anti-inflammatory cytokines, IL-4 and IL-10. The quantitative PCR results showed that SLKDT extract upregulated the mRNA expressions of peroxisome proliferator-activated receptor (PPAR)-α, lipoprotein lipase, carnitine palmitoyltransferase 1, and cholesterol 7 alpha hydroxylase and downregulated PPAR-γ and CCAAT/enhancer-binding protein-alpha mRNA expressions in the obese mouse livers to reduce adipocyte differentiation and fat accumulation, promote fat oxidation, and improve dyslipidemia, thereby inhibiting the immune response and alleviating liver injury. SLKDT shows a potential for preventing obesity and regulating obesity-related syndrome, so it is possible to be further developed as a novel treatment for fighting obesity.

miR-222 is involved in the regulation of genistein on skeletal muscle fiber type

In skeletal muscle, the composition of the fiber types has a profound impact on athletic performance, such as endurance or strength output. The proportions of muscle fiber types have also been associated with certain diseases, including dyskinesia, obesity and insulin resistance. Genistein, a natural estrogen, has been demonstrated to regulate fatty acid oxidation and insulin sensitivity in skeletal muscle. However, it is unknown whether genistein can regulate skeletal muscle fiber types. Furthermore, the mechanism of its effect on skeletal muscle energy metabolism is not entirely clear. In this study, in vivo and in vitro experiments were used to explore the effect of genistein on the muscle fiber-type transitions and muscle metabolism. The results indicated that genistein not only promotes skeletal muscle development but increases the expression of slow muscle fibers in mice as well. It was also demonstrated that genistein altered the ratios of fiber type and promoted mitochondrial biogenesis in C2C12 myoblasts. Interestingly, the expression of miR-222 was decreased by genistein, and it was demonstrated that this microRNA targets the PGC1α gene. In C2C12 myoblasts, miR-222 appears to regulate fiber type conversion and mitochondrial biogenesis. However, this function was significantly reduced following genistein treatment. These results suggest that miR-222 may be involved in the regulation of genistein on skeletal muscle fiber and muscle metabolism, and genistein may be used to improve muscle health.

Acteoside From Ligustrum robustum (Roxb.) Blume Ameliorates Lipid Metabolism and Synthesis in a HepG2 Cell Model of Lipid Accumulation

We aimed to ascertain the mechanism underlying the effects of acteoside (ACT) from Ligustrum robustum (Roxb.) Blume (Oleaceae) on lipid metabolism and synthesis. ACT, a water-soluble phenylpropanoid glycoside, is the most abundant and major active component of L. robustum; the leaves of L. robustum, known as kudingcha (bitter tea), have long been used in China as an herbal tea for weight loss. Recently, based on previous studies, our team reached a preliminary conclusion that phenylpropanoid glycosides from L. robustum most likely contribute substantially to reducing lipid levels, but the mechanism remains unclear. Here, we conducted an in silico screen of currently known phenylethanoid glycosides from L. robustum and attempted to explore the hypolipidemic mechanism of ACT, the representative component of phenylethanoid glycosides in L. robustum, using RNA-seq technology, quantitative real-time PCR (qPCR) and Western blotting. First, the screening results for six compounds were docked with 15 human protein targets, and 3 of 15 protein targets were related to cardiovascular diseases. Based on previous experimental data and docking results, we selected ACT, which exerted positive effects, for further study. We generated a lipid accumulation model using HepG2 cells treated with a high concentration of oleic acid and then extracted RNA from cells treated for 24 h with 50 μmol/L ACT. Subsequently, we performed a transcriptomic analysis of the RNA-seq results, which revealed a large number of differentially expressed genes. Finally, we randomly selected some genes and proteins for further validation using qPCR and Western blotting; the results agreed with the RNA-seq data and confirmed their reliability. In conclusion, our experiments proved that ACT from L. robustum alters lipid metabolism and synthesis by regulating the expression of multiple genes, including Scarb1, Scarb2, Srebf1, Dhcr7, Acat2, Hmgcr, Fdft1, and Lss, which are involved several pathways, such as the glycolytic, AMPK, and fatty acid degradation pathways.

Ligustrum robustum Intake, Weight Loss, and Gut Microbiota: An Intervention Trial

Ligustrum robustum (LR) shows antiobesity effects in animal studies. However, little is known about the effect on human. The present study aimed to investigate the effect of LR intake on weight change in obese women and the role of gut microbiota. Thirty overweight and obese female participants (BMI ≥24 kg/m²) were recruited in the current study. The participants drank LR 10g/d for 12 wks. Their body composition and related biomarkers were assessed. Alterations of the gut microbiota were analyzed using 16S rRNA sequencing. The primary outcome was the change in body weight. LR intake resulted in 2.5% weight loss over 12 wks (P<0.01). Change in body fat at 12 wk was -1.77 ± 1.19 kg (P<0.01). In addition, decreased Firmicutes-to-Bacteroidetes ratio (P=0.03), increased richness (the ACE estimator, P<0.01; the Chao1 estimator, P<0.01), and altered representative taxa of the gut microbiota were observed. Bacteroidaceae, Bacteroides, Bacilli, and Lactobacillales were higher while Ruminococcaceae, Enterobacteriaceae, Enterobacteriales, Lachnospiraceae, Clostridia, and Clostridiales were lower at 12 wk. Moreover, LR intervention decreased fasting glucose (P<0.01), serum leptin (P<0.01), and IL8 (P=0.02) and increased HOMA-β (P<0.01). LR intervention moderately decreased the body weight in overweight and obese women and such effect might be due to modulation of gut microbiota.

Involvement of the Hydroperoxy Group in the Irreversible Inhibition of Leukocyte-Type 12-Lipoxygenase by Monoterpene Glycosides Contained in the Qing Shan Lu Shui Tea

We have previously found two novel monoterpene glycosides, liguroside A and liguroside B, with an inhibitory effect on the catalytic activity of the enzyme leukocyte-type 12-lipoxygenase in the Qing Shan Lu Shui tea. Here, two new monoterpene glycosides, liguroside C and liguroside D which inhibit this enzyme, were isolated from the same tea. The spectral and chemical evidence characterized the structures of these compounds as (5E)-7-hydroperoxy-3,7-dimethyl-1,5-octadienyl-3-O-(α-l-rhamnopyranosyl)-(1′′→3′)-(4′′′-O-trans-p-coumaroyl)-β-d-glucopyranoside and (2E)-6-hydroxy-3,7-dimethyl-2,7-octadienyl-3-O-(α-l-rhamnopyranosyl)-(1′′→3′)-(4′′′-O-trans-p-coumaroyl)-β-d-glucopyranoside, respectively. These ligurosides, which irreversibly inhibited leukocyte-type 12-lipoxygenase, have a hydroperoxy group in the monoterpene moiety. Additionally, monoterpene glycosides had the same backbone structure but did not have a hydroperoxy group, such as kudingoside A and lipedoside B-III, contained in the tea did not inhibit the enzyme. When a hydroperoxy group in liguroside A was reduced by using triphenylphosphine, the resultant compound, kudingoside B, showed a lower inhibitory effect on the enzyme. These results strongly suggest the involvement of the hydroperoxy group in the irreversible inhibition of the catalytic activity of leukocyte-type 12-lipoxygenase by the monoterpene glycosides contained in the Qing Shan Lu Shui tea.

Dietary effect of lemon verbena extract on selected blood parameters and on plasma oxidative profile in Avelignese horses

The effect of Lippia citriodora extract on selected blood parameters and on plasma oxidative markers in Avelignese horses was evaluated. Twenty-four horses were divided into three groups, consisting of eight animals each. Results of two experimental groups, 0.5 mg of verbascoside per kg of metabolic body weight (bw^0.75 ) in the low-dose group (LVB) and 1.0 mg of verbascoside per kg of metabolic body weight (bw^0.75 ) in the high-dose group (HVB), were compared to the control group (CON). Groups fed L. citriodora extract (HVB and LVB) showed a significant decrease in triglycerides, total cholesterol and LDL cholesterol (p < .01), bilirubin, and transaminases (p < .05), and an increase in HDL cholesterol (p < .01) compared to the CON group. Oxidative status was improved due to significant decrease in plasma concentration of ROMs and TBARS (p < .01) and increase in levels of vitamin A and vitamin E (p < .01). Based on obtained results, it is assumed that dietary supplementation with L. citriodora extract might find a useful application in horse feeding, with positive impact observed in blood parameters and plasma oxidative markers, with beneficial effects on the physiological welfare of livestock animals.

Inhibitory effect of Ligustrum vulgare leaf extract on the development of neuropathic pain in a streptozotocin-induced rat model of diabetes

BACKGROUND

Chronic hyperalgesia and allodynia associated with progressive damage of peripheral neurons are the most prevalent complications of diabetes mellitus. Plants belonging to the family of Oleaceae were traditionally used in folk medicine for the management of diabetes.

HYPOTHESIS/PURPOSE

The aim of this study was to investigate whether an aqueous extract from the leaves of Ligustrum vulgare (common privet) could be useful to target neuropathic pain in a rat streptozotocin (STZ) model of diabetes.

METHODS

The chemical composition of the aqueous extract from privet leaf was characterized with the UHPLC-DAD-MS method and the analytical quantification of its constituents was performed with HPLC-DAD. Mechanical hyperalgesia and allodynia were evaluated with the Randall-Selitto and von Frey tests.

RESULTS

Our investigation revealed the presence of secoiridoids: oleacein (23.48 ± 0.87 mg/g), oleocanthal (8.44 ± 0.08 mg/g), oleuropein (1.50 ± 0.01 mg/g), as well as phenylpropanoids: echinacoside (6.46 ± 0.07 mg/g), verbascoside (4.03 ± 0.04 mg/g) and p-coumaroyl glucarates in the dried aqueous extract of privet leaves. Behavioral data indicated that chronic intraperitoneal administration of the extract (50-200 mg/kg) for 21 days resulted in a decrease in diabetes-induced hyperalgesia and allodynia. Blood glucose levels remained unaltered, while body weight and water intake decreased significantly.

CONCLUSION

The aqueous privet leaf extract could serve useful in facilitating treatment of painful diabetic neuropathy. Additionally, the study showed that the antihyperalgesic activity of Ligustrum vulgare leaf extract is not likely related to its antihyperglycemic properties.

Plantago asiatica L. Seed Extract Improves Lipid Accumulation and Hyperglycemia in High-Fat Diet-Induced Obese Mice

Obesity and its common association with type 2 diabetes, dyslipidemia, and cardiovascular diseases are worldwide epidemics. Currently, to prevent or treat obesity and associated metabolic disorders, herbal dietary supplements or medicines have attracted more and more attention owing to their relative effectiveness with fewer significant side effects. We investigate the therapeutic effects and underlying mechanisms of Plantago asiatica L. seed extract (PSE) on obesity and associated metabolic disorders in high-fat (HF) diet-induced mice. Our results displayed that PSE did not modify food intake or body weight but decreased abdominal white adipose tissue ratio, white/brown adipocyte size, serum total cholesterol, triglyceride (TG), low density lipoprotein cholesterol, free fatty acid, and hepatic TG concentrations when compared with the HF group. The levels of fasting blood glucose and glucose tolerance were improved in the PSE group when compared with the HF group. Furthermore, PSE upregulated mRNA expressions of peroxisome proliferator activated receptors (PPARs) and target genes related to fatty acid metabolism and energy expenditure in liver and adipose tissue of obese mice when compared with the HF group. PSE treatment effectively improved lipid and glucose metabolism in HF diet-induced obese mice. These effects might be attributed to the upregulation of PPAR signaling.

Chrysoeriol and other polyphenols from Tecoma stans with lipase inhibitory activity

ETHNOPHARMACOLOGICAL RELEVANCE

Tecoma stans is traditionally used by several ethnical groups in Mexico and Central America to treat diabetes. This species is mentioned in the majority of the ethnopharmacological studies compiled in Mexico focused in medicinal plants used as anti-diabetic treatment.

AIM OF THE STUDY

Recently, this plant was found to display a high level of pancreatic lipase inhibitory activity, in addition to the several action mechanisms already described. Here we show the phytochemical and in vitro pharmacological characterization of some of the compounds responsible for the antilipase activity.

MATERIALS AND METHODS

Starting with a hydroalcoholic extract, fractions were obtained by liquid-liquid separation and successive processes of column chromatography purifications. Lipase inhibitory activity was measured employing a spectrophotometric analysis. For structural elucidation (1)H and (13)C NMR experiments were used. HPLC was used to quantify and confirm the identity of the bioactive compounds.

RESULTS

Bio-guided chemical purification of the hydroalcoholic extract produced an organic fraction (ethyl acetate, TsEA), flavone fractions (TsC1F13), (TsC1F15), (TsC1F16) and isolated compounds (chrysoeriol, apigenin, luteolin, and verbascoside) with the capability to inhibit the activity of pancreatic lipase. The most active fraction (TsC2F6B) was constituted by a mixture of Chrysoeriol (5,7-dihydroxy-2-[4-hydroxy-3-methoxyphenyl]chromen-4-one, 96% ) and Apigenin (4%). This flavone mixture displayed a percentage of inhibition of 85% when it was eavaluated at 0.25mg/mL. Luteolin and chrysoeriol produced a noncompetitive and mixed inhibition with values of IC50=63 and 158µM respectively. The content of chrysoeriol was also quantified in the hydroalcoholic extract (TsHAE) and organic fraction (TsEA) as 1% and 7% respectively. All of this confirms that high proportion of both flavones produce an increase of the biological activity due to they show the highest inhibition of lipase enzyme in a concentration dependant way.

CONCLUSIONS

These results evidence that the medicinal use of T. stans could be in part because of its lipase inhibitory activity allowing to adapt the administration of this plant before meals. Also this data could help to develop a novel phytopharmaceutical drug (standardized in luteolin, chrysoeriol, and apigenin) auxiliary for the Type 2 Diabetes mellitus.