Hypoglycemic and hypolipidemic effects of Epigynum auritum in high fat diet and streptozotocin-induced diabetic rats

In Vitro Anti-Tumor and Hypoglycemic Effects of Total Flavonoids from Willow Buds

Salix babylonica L. is a species of willow tree that is widely cultivated worldwide as an ornamental plant, but its medicinal resources have not yet been reasonably developed or utilized. Herein, we extracted and purified the total flavonoids from willow buds (PTFW) for component analysis in order to evaluate their in vitro anti-tumor and hypoglycemic activities. Through Q-Orbitrap LC-MS/MS analysis, a total of 10 flavonoid compounds were identified (including flavones, flavan-3-ols, and flavonols). The inhibitory effects of PTFW on the proliferation of cervical cancer HeLa cells, colon cancer HT-29 cells, and breast cancer MCF7 cells were evaluated using an MTT assay. Moreover, the hypoglycemic activity of PTFW was determined by investigating the inhibitory effects of PTFW on α-amylase and α-glucosidase. The results indicated that PTFW significantly suppressed the proliferation of HeLa cells, HT-29 cells, and MCF7 cells, with IC50 values of 1.432, 0.3476, and 2.297 mg/mL, respectively. PTFW, at different concentrations, had certain inhibitory effects on α-amylase and α-glucosidase, with IC50 values of 2.94 mg/mL and 1.87 mg/mL, respectively. In conclusion, PTFW at different doses exhibits anti-proliferation effects on all three types of cancer cells, particularly on HT-29 cells, and also shows significant hypoglycemic effects. Willow buds have the potential to be used in functional food and pharmaceutical industries.

Roles of protein post-translational modifications in glucose and lipid metabolism: mechanisms and perspectives

The metabolism of glucose and lipids is essential for energy production in the body, and dysregulation of the metabolic pathways of these molecules is implicated in various acute and chronic diseases, such as type 2 diabetes, Alzheimer's disease, atherosclerosis (AS), obesity, tumor, and sepsis. Post-translational modifications (PTMs) of proteins, which involve the addition or removal of covalent functional groups, play a crucial role in regulating protein structure, localization function, and activity. Common PTMs include phosphorylation, acetylation, ubiquitination, methylation, and glycosylation. Emerging evidence indicates that PTMs are significant in modulating glucose and lipid metabolism by modifying key enzymes or proteins. In this review, we summarize the current understanding of the role and regulatory mechanisms of PTMs in glucose and lipid metabolism, with a focus on their involvement in disease progression associated with aberrant metabolism. Furthermore, we discuss the future prospects of PTMs, highlighting their potential for gaining deeper insights into glucose and lipid metabolism and related diseases.

Dietary regulation of peroxisome proliferator-activated receptors in metabolic syndrome

BACKGROUND

Peroxisome proliferator-activated receptors (PPARs) are a class of ligand-activated nuclear transcription factors, members of the type nuclear receptor superfamily, with three subtypes, namely PPARα, PPARβ/δ, and PPARγ, which play a key role in the metabolic syndrome. In the past decades, a large number of studies have shown that natural products can act by regulating metabolic pathways mediated by PPARs.

PURPOSE

This work summarizes the physiological importance and clinical significance of PPARs and reviews the experimental evidence that natural products mediate metabolic syndrome via PPARs.

METHODS

This study reviews relevant literature on clinical trials, epidemiology, animals, and cell cultures published in NCBI PubMed, Scopus, Web of Science, Google Scholar, and other databases from 2001 to October 2022. Search keywords were "natural product" OR "botanical" OR "phytochemical" AND "PPAR" as well as free text words.

RESULTS

The modulatory involvement of PPARs in the metabolic syndrome has been supported by prior research. It has been observed that many natural products can treat metabolic syndrome by altering PPARs. The majority of currently described natural compounds are mild PPAR-selective agonists with therapeutic effects that are equivalent to synthetic medicines but less harmful adverse effects.

CONCLUSION

PPAR agonists can be combined with natural products to treat and prevent metabolic syndrome. Further human investigations are required because it is unknown how natural products cause harm and how they might have negative impacts.

E Se tea extract ameliorates CCl4 induced liver fibrosis via regulating Nrf2/NF-κB/TGF-β1/Smad pathway

BACKGROUND

Liver fibrosis is a crucial progress to deteriorate liver disease. E Se tea (ES) is an ethnic herbal tea in China that has various biological activities for human beings. However, the traditional application on the treatment of liver disease is not studied.

PURPOSE

This study is firstly performed to explore the chemical constituents of ES extract together with its anti-hepatic fibrosis effect and potential mechanism on CCl₄ treated mice.

STUDY DESIGN AND METHODS

The chemical constituents of ethanol-aqueous extract from ES (ESE) were analyzed by UPLC-ESI-MS/MS. The anti-hepatic fibrosis effect of ESE was determined by measuring ALT and AST activities, antioxidative indexes, inflammatory cytokines and collagen protein levels on CCl₄ treated mice. Moreover, H&E, Masson staining and immunohistochemical analysis were performed for evaluating the protective effect of ESE on histopathological changes of liver tissues.

RESULTS

UHPLCHRESI-MS/MS analysis showed that the ESE was rich in flavonoids such as phlorizin, phloretin, quercetin and hyperoside. ESE could significantly reduce the plasma AST and ALT activities. The cytokines (IL-6, TNF-α, IL-1β) expressions were inhibited after ESE administration via suppressing NF-κB pathway. In addition, ESE could decrease MDA accumulation for alleviating CCl₄ induced liver oxidative stress via regulating Nrf2 pathway to promote the expressions of antioxidant enzymes (SOD, HO-1, CAT and NQO1). Moreover, ESE could inhibit the expressions of TGF-β1, Smad2, α-SMA, and collagens Ⅰ and III proteins, thereby effectively alleviate the liver fibrosis.

CONCLUSION

This study demonstrated that ESE could alleviate liver fibrosis through enhancing antioxidant and anti-inflammatory abilities by Nrf2/NF-κB pathway and reducing deposition of liver fibrosis via suppressing TGF-β/Smad pathway.

Antidiabetic and antioxidant activities of Mitragyna speciosa (kratom) leaf extract in type 2 diabetic rats

Mitragyna speciosa is a medicinal plant with a reputation for treating pains, diabetes as well as increasing energy and sexual desires. However, there is no scientific evidence to validate the antidiabetic effect of M. speciosa. This study investigated the antidiabetic effects of M. speciosa (Krat) ethanolic extract on fructose and streptozocin (STZ)-induced type 2 diabetic rats. In vitro antioxidant and antidiabetic effects were evaluated using DPPH, ABST, FRAP and α-glucosidase inhibitory assays. Rats with fructose/STZ induced T2D were treated with Krat (100 and 400 mg/kg) or metformin (200 mg/kg) for 5 weeks via oral gavage. Krat showed good antioxidant activity and also displayed potent α-glucosidase inhibitory activity. Administration of Krat to the diabetic rats significantly improved body weight gain, restored alterations in blood glucose level, glucose tolerance, dyslipidemia (increased cholesterol, triglycerides, low-density lipoprotein-cholesterol and reduced high-density lipoprotein), hepatorenal biomarkers alterations (alanine transaminase, aspartate transaminase, alanine phosphatase, creatinine and blood urea nitrogen) and oxidative stress indices (superoxide dismutase, glutathione and malondialdehyde)in the treated diabetic rats. Furthermore, Krat also restored pancreatic histological and increased immunohistochemical aberrations in the diabetic rats. These results for the first time demonstrated the antidiabetic and antihyperlipidemic potentials of M. speciosa, thus providing scientific reinforcement for the traditional use of the plant in the treatment of diabetes.

Effects of Rice-Husk Silica Liquid in Streptozotocin-Induced Diabetic Mice

Type 2 diabetes mellitus is a complex multifactorial disease characterized by poor glucose tolerance and insulin resistance. Rice-husk silica liquid (RHSL) derived from rice husk has the ability to improve the dysfunction of pancreatic β-cells. This study aimed to confirm the potential protective effects of RHSL in streptozotocin (STZ)-induced diabetic mice. Diabetes was induced in male C57BL/6J mice by intraperitoneal administration of STZ (200 mg/kg BW). RHSL, food-grade silica liquid (FDSL), and rosiglitazone (RSG) were administered to diabetic mice for 12 weeks after successful induction of diabetes. During the experiment, fasting blood glucose, serum insulin, and organ weights were measured. The histopathology of liver tissue was evaluated by H&E staining. Western blotting was performed to assess protein expression levels. The results showed that RHSL significantly reversed the serum insulin levels and improved oral glucose tolerance test (OGTT) results (p < 0.05). In addition, liver sections of STZ-induced diabetic mice after RHSL treatment showed neatly arranged and intact hepatocytes. Furthermore, RHSL was more effective than FDSL in increasing the expression of SIRT1 and decreasing the expression of the PPAR-γ and p-NF-κB proteins. Taken together, this study demonstrated that RHSL ameliorated STZ-induced insulin resistance and liver tissue damage in C57BL/6J mice.

Ethanolic Extract from Pteris wallichiana Alleviates DSS-Induced Intestinal Inflammation and Intestinal Barrier Dysfunction by Inhibiting the TLR4/NF-κB Pathway and Regulating Tight Junction Proteins

The aim of the research was to determine the protective effect and mechanism of Pteris wallichiana J. Agardh extract (PWE) on DSS-induced ulcerative colitis (UC) in mice. In this research, PWE is rich in flavonoids and diterpenoids by UPLC-MS/MS analysis. In LPS-induced RAW264.7 cells, PWE reduced the productions of inflammatory factors (i.e., NO, TNF-α, IL-6, and IL-1β). In DSS-induced UC in mice, PWE improved disease activity index (DAI) score, attenuated oxidative stress by decreasing MPO and MDA activities and activating GSH and SOD levels, and inhibited TNF-α, IL-6, and IL-1β expressions in the colonic tissues. PWE also improved the intestinal barrier by upregulating the expressions of tight junction proteins, including occludin and ZO-1. Moreover, PWE extract alleviated intestinal inflammation by suppressing the TLR4/MyD88/NF-κB signaling pathway. Conclusion: PWE can alleviate DSS-induced UC in mice by increasing the expressions of intestinal tight junction proteins and inhibiting the TLR4/NF-κB inflammatory pathway.