Vaccarin enhances intestinal barrier function in type 2 diabetic mice

Evidence of traditional Chinese medicine for treating type 2 diabetes mellitus: from molecular mechanisms to clinical efficacy

CONTEXT

The global prevalence of type 2 diabetes mellitus (T2DM) has increased significantly in recent decades. Despite numerous studies and systematic reviews, there is a gap in comprehensive and up-to-date evaluations in this rapidly evolving field.

OBJECTIVE

This review provides a comprehensive and current overview of the efficacy of Traditional Chinese Medicine (TCM) in treating T2DM.

METHODS

A systematic review was conducted using PubMed, Web of Science, Wanfang Data, CNKI, and Medline databases, with a search timeframe extending up to November 2023. The search strategy involved a combination of subject terms and free words in English, including 'Diabetes,' 'Traditional Chinese Medicine,' 'TCM,' 'Hypoglycemic Effect,' 'Clinical Trial,' and 'Randomized Controlled Trial.' The studies were rigorously screened by two investigators, with a third investigator reviewing and approving the final selection based on inclusion and exclusion criteria.

RESULTS

A total of 108 relevant papers were systematically reviewed. The findings suggest that TCMs not only demonstrate clinical efficacy comparable to existing Western medications in managing hypoglycemia but also offer fewer adverse effects and a multitarget therapeutic approach. Five main biological mechanisms through which TCM treats diabetes were identified: improving glucose transport and utilization, improving glycogen metabolism, promoting GLP-1 release, protecting pancreatic islets from damage, and improving intestinal flora.

CONCLUSIONS

TCM has demonstrated significant protective effects against diabetes and presents a viable option for the prevention and treatment of T2DM. These findings support the further exploration and integration of TCM into broader diabetes management strategies.

Repairing gut barrier by traditional Chinese medicine: roles of gut microbiota

Gut barrier is not only part of the digestive organ but also an important immunological organ for the hosts. The disruption of gut barrier can lead to various diseases such as obesity and colitis. In recent years, traditional Chinese medicine (TCM) has gained much attention for its rich clinical experiences enriched in thousands of years. After orally taken, TCM can interplay with gut microbiota. On one hand, TCM can modulate the composition and function of gut microbiota. On the other hand, gut microbiota can transform TCM compounds. The gut microbiota metabolites produced during the actions of these interplays exert noticeable pharmacological effects on the host especially gut barrier. Recently, a large number of studies have investigated the repairing and fortifying effects of TCM on gut barriers from the perspective of gut microbiota and its metabolites. However, no review has summarized the mechanism behand this beneficiary effects of TCM. In this review, we first briefly introduce the unique structure and specific function of gut barrier. Then, we summarize the interactions and relationship amidst gut microbiota, gut microbiota metabolites and TCM. Further, we summarize the regulative effects and mechanisms of TCM on gut barrier including physical barrier, chemical barrier, immunological barrier, and microbial barrier. At last, we discuss the effects of TCM on diseases that are associated gut barrier destruction such as ulcerative colitis and type 2 diabetes. Our review can provide insights into TCM, gut barrier and gut microbiota.

Vaccarin Ameliorates Doxorubicin-Induced Cardiotoxicity via Inhibition of p38 MAPK Mediated Mitochondrial Dysfunction

Doxorubicin is a frequently used chemotherapeutic agent for treating various malignancies. However, it leads to severe cardiotoxic side effects, such as heart failure, and elevates the risk of sudden cardiac death among cancer patients. While oxidative stress has been identified as the primary cause of doxorubicin-induced cardiotoxicity, therapeutic antioxidant approaches have yielded unsatisfactory outcomes. The aim of this study is to explore the therapeutic potential of vaccarin, an active flavonoid glycoside extracted from traditional Chinese herbal agent Semen Vaccariae, in doxorubicin-induced cardiotoxicity. We observed that vaccarin significantly ameliorates doxorubicin-induced heart dysfunction in mouse model and suppresses oxidative stress mediated cell apoptosis via specifically inhibiting the activation of p38 MAPK pathway. In vitro, we observed that vaccarin alleviates doxorubicin-induced mitochondrial membrane depolarization and ROS generation in H9c2 cell, but the p38 MAPK agonist anisomycin reverses these effects. Our findings provide a promising natural antioxidant to protect against DOX-induced cardiotoxicity.

From ancient wisdom to modern science: Gut microbiota sheds light on property theory of traditional Chinese medicine

The property theory of traditional Chinese medicine (TCM) has been practiced for thousands of years, playing a pivotal role in the clinical application of TCM. While advancements in energy metabolism, chemical composition analysis, machine learning, ion current modeling, and supercritical fluid technology have provided valuable insight into how aspects of TCM property theory may be measured, these studies only capture specific aspects of TCM property theory in isolation, overlooking the holistic perspective inherent in TCM. To systematically investigate the modern interpretation of the TCM property theory from multidimensional perspectives, we consulted the Chinese Pharmacopoeia (2020 edition) to compile a list of Chinese materia medica (CMM). Then, using the Latin names of each CMM and gut microbiota as keywords, we searched the PubMed database for relevant research on gut microbiota and CMM. The regulatory patterns of different herbs on gut microbiota were then summarized from the perspectives of the four natures, the five flavors and the meridian tropism. In terms of the four natures, we found that warm-natured medicines promoted the colonization of specific beneficial bacteria, while cold-natured medicines boosted populations of some beneficial bacteria while suppressing pathogenic bacteria. Analysis of the five flavors revealed that sweet-flavored and bitter-flavored CMMs positively influenced beneficial bacteria while inhibiting harmful bacteria. CMMs with different meridian tropism exhibited complex modulative patterns on gut microbiota, with Jueyin (Liver) and Taiyin (Lung) meridian CMMs generally exerting a stronger effect. The gut microbiota may be a biological indicator for characterizing the TCM property theory, which not only enhances our understanding of classic TCM theory but also contributes to its scientific advancement and application in healthcare. Please cite this article as: Yang YN, Zhan JG, Cao Y, Wu CM. From ancient wisdom to modern science: Gut microbiota sheds light on property theory of traditional Chinese medicine. J Integr Med. 2024; Epub ahead of print.

Potential efficacy and mechanism of eight mild-natured and bitter-flavored TCMs based on gut microbiota: A review

The mild-natured and bitter-flavored traditional Chinese medicines (MB-TCMs) are an important class of TCMs that have been widely used in clinical practice and recognized as safe long-term treatments for chronic diseases. However, as an important class of TCMs, the panorama of pharmacological effects and the mechanisms of MB-TCMs have not been systemically reviewed. Compelling studies have shown that gut microbiota can mediate the therapeutic activity of TCMs and help to elucidate the core principles of TCM medicinal theory. In this systematic review, we found that MB-TCMs commonly participated in the modulation of metabolic syndrome, intestinal inflammation, nervous system disease and cardiovascular system disease in association with promoting the growth of beneficial bacteria Bacteroides, Akkermansia, Lactobacillus, Bifidobacterium, Roseburia as well as inhibiting the proliferation of harmful bacteria Helicobacter, Enterococcus, Desulfovibrio and Escherichia-Shigella. These alterations, correspondingly, enhance the generation of protective metabolites, mainly including short-chain fatty acids (SCFAs), bile acid (BAs), 5-hydroxytryptamine (5-HT), indole and gamma-aminobutyric acid (GABA), and inhibit the generation of harmful metabolites, such as proinflammatory factors trimethylamine oxide (TAMO) and lipopolysaccharide (LPS), to further exert multiplicative effects for the maintenance of human health through several different signaling pathways. Altogether, this present review has attempted to comprehensively summarize the relationship between MB-TCMs and gut microbiota by establishing the TCMs-gut microbiota-metabolite-signaling pathway-diseases axis, which may provide new insight into the study of TCM medicinal theories and their clinical applications.

Vaccarin alleviates cisplatin-induced acute kidney injury via decreasing NOX4-derived ROS

Cisplatin is a chemotherapeutant widely used in treating solid tumors, with the common side effect of acute kidney injury (AKI). Developing effective useful agent for preventing or treating cisplatin-induced AKI is of great importance. In this study, we investigate the protective effect of vaccarin, a chemical entity of flavonoid glycoside, against cisplatin-induced AKI. Cisplatin-treated C57BL/6J mice and human kidney-2 (HK-2) cells were used as the model of cisplatin-induced AKI. The levels of blood urea nitrogen (BUN) and creatine (Cr) levels and periodic acid-Schiff staining (PAS) scores decreased when vaccarin was administrated. Vaccarin had no impact on renal platinum accumulation, which was detected by the ICP-MS 6 h after cisplatin injection. Moreover, vaccarin can significantly alleviate the product of reactive oxygen species and the expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 4 (NOX4) in cisplatin-induced AKI, both in vivo and in vitro. In addition, vaccarin decreased the receptor-interacting protein kinase 1 (RIPK1) related programmed necrosis (necroptosis), cell apoptosis (shown by the protein levels of cleaved-caspase3 and flow cytometry) and inflammation (shown by the decreased levels of NLRP3, p-P65 and the mRNA of several inflammatory factors). NOX4 inhibitor GLX351322 (GLX) and NOX4 kowndown by siRNA have equivalent protective effect of vaccarin in vitro. When vaccarin was administered together with GLX or NOX4 siRNA, this protective effect of vaccarin did not further increase, as indicating by the index of oxidative stress, cell viability, necroptosis and apoptosis. In conclusion, vaccarin can alleviate cisplatin-induced AKI via inhibiting NOX4.

Berberine alleviates intestinal barrier dysfunction in glucolipid metabolism disorder hamsters by modulating gut microbiota and gut-microbiota-related tryptophan metabolites

BACKGROUND

Barberry plants can be considered as useful additives and functional compounds in various industries, especially in the food industry. Berberine (BBR), the most important functional compound in the barberry roots, has recently been used to treat obesity, diabetes, and atherosclerosis. Gut microbiota and the intestinal barrier play an important role in the development of glucolipid metabolism disorders (GLMDs). However, the association of gut microbiota metabolism disorder and the intestinal barrier dysfunction effect of BBR in GLMDs remains elusive.

RESULTS

The results showed that administration of BBR could increase the number of colonic glands and goblet cell mucus secretion, improve the intestinal barrier function, and reduce the serum glycolipid level in GLMD hamsters. Interestingly, BBR was metabolized into 12 metabolites by gut microbiota, and the main metabolic pathways were oxidation, demethylation, and hydrogenation. In addition, BBR significantly improved the species diversity and uniformity of gut microbiota and promoted the proliferation of beneficial microbiota. Furthermore, the levels of tryptophan metabolites, such as indole, indole-3-acetamide, indole-3-acetaldehyde, indole-3-pyruvic acid, and indole-3-acetic acid were significantly altered by BBR. Both the intestinal tight junction proteins and intestinal immune factors were altered by BBR.

CONCLUSION

BBR could alleviate intestinal barrier dysfunction of GLMDs by modulating gut microbiota and gut-microbiota-related tryptophan metabolites, which may be one of the pharmacological mechanisms for the treatment of GLMDs. © 2022 Society of Chemical Industry.

Surfactin Mitigates a High-Fat Diet and Streptozotocin-Induced Type 2 Diabetes through Improving Pancreatic Dysfunction and Inhibiting Inflammatory Response

Surfactin from Bacillus amyloliquefaciens fmb50 was utilized to treat mice with type 2 diabetes (T2DM) induced by a high-fat diet/streptozotocin (HFD/STZ). Our group’s earlier research indicated that surfactin could lower blood glucose and mitigate liver dysfunction to further improve HFD/STZ-induced T2DM through modulating intestinal microbiota. Thus, we further investigated the effects of surfactin on the pancreas and colon in mice with T2DM to elucidate the detailed mechanism. In the present study, mice with HFD/STZ-induced T2DM had their pancreatic and colon inflammation, oxidative stress, and endoplasmic reticulum stress (ERS) reduced when given oral surfactin at a dose of 80 mg/kg body weight. According to further research, surfactin also improved glucose metabolism by activating the phosphatidylinositol kinase (PI3K)/protein kinase B (Akt) signaling pathway, further protecting islets β-cell, promoting insulin secretion, inhibiting glucagon release and mitigating pancreas dysfunction. Additionally, after surfactin treatment, the colon levels of the tight junction proteins Occludin and Claudin-1 of T2DM mice were considerably increased by 130.64% and by 36.40%, respectively. These findings revealed that surfactin not only ameliorated HFD/STZ-induced pancreas inflammation and dysfunction and preserved intestinal barrier dysfunction and gut microbiota homeostasis but also enhanced insulin sensitivity and glucose homeostasis in T2DM mice. Finally, in the further experiment, we were able to demonstrate that early surfactin intervention might delay the development of T2DM caused by HFD/STZ, according to critical biochemical parameters in serum.

Vaccarin alleviates endothelial inflammatory injury in diabetes by mediating miR-570-3p/HDAC1 pathway

Vaccarin is a flavonoid glycoside, which has a variety of pharmacological properties and plays a protective role in diabetes and its complications, but its mechanism is unclear. In this study, we aim to investigate whether histone deacetylase 1(HDAC1), a gene that plays a pivotal role in regulating eukaryotic gene expression, is the target of miR-570-3p in diabetic vascular endothelium, and the potential molecular mechanism of vaccarin regulating endothelial inflammatory injury through miR-570-3p/HDAC1 pathway. The HFD and streptozotocin (STZ) induced diabetes mice model, a classical type 2 diabetic model, was established. The aorta of diabetic mice displayed a decrease of miR-570-3p, the elevation of HDAC1, and inflammatory injury, which were alleviated by vaccarin. Next, we employed the role of vaccarin in regulating endothelial cells miR-570-3p and HDAC1 under hyperglycemia conditions in vitro. We discovered that overexpression of HDAC1 counteracted the inhibitory effect of vaccarin on inflammatory injury in human umbilical vein endothelial cells (HUVECs). Manipulation of miRNA levels in HUVECs was achieved by transfecting cells with miR-570-3p mimic and inhibitor. Overexpression of miR-570-3p could decrease the expression of downstream components of HDAC1 including TNF-α, IL-1β, and malondialdehyde, while increasing GSH-Px activity in HUVECs under hyperglycemic conditions. Nevertheless, such phenomenon was completely reversed by miR-570-3p inhibitor, and administration of miR-570-3p inhibitor could block the inhibition of vaccarin on HDAC1 and inflammatory injury. Luciferase reporter assay confirmed the 3′- UTR of the HDAC1 gene was a direct target of miR-570-3p. In summary, our findings suggest that vaccarin alleviates endothelial inflammatory injury in diabetes by mediating miR-570-3p/HDAC1 pathway. Our study provides a new pathogenic link between deregulation of miRNA expression in the vascular endothelium of diabetes and inflammatory injury and provides new ideas, insights, and choices for the scope of application and medicinal value of vaccarin and some potential biomarkers or targets in diabetic endothelial dysfunction and vascular complications.

Regulation of the intestinal flora: A potential mechanism of natural medicines in the treatment of type 2 diabetes mellitus

Diabetes mellitus comprises a group of heterogeneous disorders, which are usually subdivided into type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM). Both genetic and environmental factors have been implicated in the onset of diabetes. Type 1 diabetes primarily involves autoimmune insulin deficiency. In comparison, type 2 diabetes is contributed by the pathological state of insulin deficiency and insulin resistance. In recent years, significant differences were found in the abundance of microflora, intestinal barrier, and intestinal metabolites in diabetic subjects when compared to normal subjects. To further understand the relationship between diabetes mellitus and intestinal flora, this paper summarizes the interaction mechanism between diabetes mellitus and intestinal flora. Furthermore, the natural compounds found to treat diabetes through intestinal flora were classified and summarized. This review is expected to provide a valuable resource for the development of new diabetic drugs and the applications of natural compounds.