Lyoniresinol 3α-O-β-D-glucopyranoside-mediated hypoglycaemia and its influence on apoptosis-regulatory protein expression in the injured kidneys of streptozotocin-induced mice

The antidiabetic properties of lignans: a comprehensive review

BACKGROUND

Diabetes mellitus (DM) is a chronic metabolic disease with a high global prevalence. Lignans, a class of plant natural compounds found in commonly consumed foods, are well-tolerated by humans and have demonstrated promising potential in the management of DM. Consumption of lignan-rich foods has been associated with improved overall health and quality of life.

PURPOSE

The clinical and preclinical evidence on the role of lignans in managing DM are critically examined.

METHODS

A thorough literature search was conducted across major scientific databases, focusing on studies that reported the effects of individual lignans on key diabetes indicators, such as glucose utilisation and insulin sensitivity, in both human and animal models, as well as in cell-based studies.

RESULTS

A total of 180 lignans were included in the review. Out of these, only three were investigated in randomised clinical trials in humans and 31 in animal models. The reviewed evidence suggests some beneficial effects of lignans in preventing the development of obesity-related diabetes. Their therapeutic benefits in preventing diabetes-related complications, particularly diabetic nephropathy, in both type 1 and type 2 diabetes, are also supported. Metabolites of various lignans, produced by microbial metabolism in the gut and serum enzymes, appear to be key bioactive forms, highlighting the need for detailed pharmacodynamic studies, optimised dosage designs, and the use of the appropriate lignan molecules for cell-based screening.

CONCLUSION

Lignans and their microbial metabolites show promise in preventing obesity-related diabetes and mitigating diabetes-related complications such as diabetic nephropathy, though further clinical studies are needed to optimize their therapeutic potential.

Analyzing chemical composition of Sargentodoxae caulis water extract and their hypouricemia effect in hyperuricemic mice

Hyperuricemia (HUA) is a metabolic disease characterized by the increase of serum uric acid (UA) level. Sargentodoxae Caulis (SC) is a commonly used herbal medicine for the treatment of gouty arthritis, traumatic swelling, and rheumatic arthritis in clinic. In this study, a total of fifteen compounds were identified in SC water extract using UHPLC-Q-TOF-MS/MS, including three phenolic acids, seven phenolic glycosides, four organic acids, and one lignan. Then, to study the hypouricemia effect of SC, a HUA mouse model was induced using a combination of PO, HX, and 20% yeast feed. After 14 days of treatment with the SC water extract, the levels of serum UA, creatinine (CRE), blood urea nitrogen (BUN) were reduced significantly, and the organ indexes were restored, the xanthine oxidase (XOD) activity were inhibited as well. Meanwhile, SC water extract could ameliorate the pathological status of kidneys and intestine of HUA mice. Additionally, quantitative real-time PCR (qRT-PCR) and western blotting results showed that SC water extract could increase the expression of ATP binding cassette subfamily G member 2 (ABCG2), organic cation transporter 1 (OCT1), organic anion transporter 1 (OAT1) and organic anion transporter 3 (OAT3), whereas decrease the expression of glucose transporter 9 (GLUT9). This study provided a data support for the clinical application of SC in the treatment of HUA.

Genus Barleria L. (Acanthaceae): a review of its taxonomy, cytogenetics, phytochemistry and pharmacological potential

OBJECTIVES

Barleria, a large genus of the Acanthaceae family, comprises more than 300 species with diverse taxonomy, cytogenetics, phytochemistry and pharmacological potential. Therefore, the aim of this review is to critically assess the research on Barleria and provide guidance for future investigations.

METHODS

The data were obtained from different sources, such as books, theses, journals and some of the websites and internet-based searches, published from 1901 to 2020. Data obtained from PubMed, Google Scholar, ScienceDirect, online electronic journals, SpringerLink, Wiley, etc. have also been used.

KEY FINDINGS

The species of this genus exhibit considerable medicinal properties. Cytogenetical data are scantily available with chromosome counts available for only 24 species. The most common chromosome number is 2n = 2x = 40. So far, 187 compounds are reported from Barleria species. The active principles, their uses, toxicity and pharmacological effects are discussed. Essential oils, flavones, flavonoids, glycosides, terpenes and terpenoids form the major compounds.

SUMMARY

It is highly recommended that the pharmacological and economic potential of Barleria species should be exploited and more detailed studies and attention be geared towards its utilization and conservation. In addition, to ensure maximum pharmacological benefits and sustainable use, it is necessary to have empirical information explaining its ethnobotanical values as well as commercial potential.

Traditional Uses, Phytochemical Constituents and Pharmacological Properties of Averrhoa carambola L.: A Review

Averrhoa carambola L. (star fruit) is an edible fruit that is extensively cultivated in southern China, Southeast Asia, India, and northern South America. It has a sweet and juicy taste and is frequently used in fruit salads and fruit platters, as a garnish in cocktail drinks and beverages, or squeezed into juice and served as a beverage. Traditionally, it has been used for treating diabetes and diabetic nephropathy, arthralgia, vomiting, lithangiuria, coughing, hangovers, and chronic paroxysmal headache for thousands of years. Currently, approximately 132 compounds have been isolated from A. carambola. Among them, flavonoids, benzoquinone, and their glycosides have been considered as biologically active substances, which are responsible for various biological activities. Pharmacological studies have revealed that crude extracts or monomeric compounds from A. carambola exhibit multiple bioactivities, such as anti-oxidant, anti-hyperglycemic, anti-obesity, anti-hyperlipidemic, anti-tumor, anti-inflammatory, hepatoprotective, cardioprotective, anti-hypertensive, neuroprotective, and others. Thus, A. carambola is a valuable treatment in Chinese medicine with therapeutic potential for multiple diseases, especially diabetes and diabetes-related diseases. Even though it is a very promising candidate in the development of functional food and the pharmaceutical industry, reports on its bioactivities have only been conducted in vivo and in vitro and there is a gap in research regarding clinical settings and safety. This review therefore provides a comprehensive and systematic overview of current progress on botany, ethnopharmacology, phytochemistry, pharmacology, and toxicity of A. carambola, providing a valuable reference for further developments and applications of A. carambola in the pharmaceutical industry and functional food.

Recent advances in chemistry and bioactivity of Sargentodoxa cuneata

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Sargentodoxa comprises only one species, Sargentodoxa cuneata (Oliv.) Rehd et al., widely distributed in the subtropical zone of China. The plant is extensively used in traditional medicine for treating arthritis, joint pains, amenorrhea, acute appendicitis and inflammatory intestinal obstruction. Pharmacological studies show anti-inflammatory, antioxidant, antitumor, antimicrobial, and anti-sepsis activities.

AIM OF THE REVIEW

This review aims to summarize the information about distribution, traditional uses, chemical constituents and pharmacological activities of S. cuneata, as an attempt to provide a scientific basis for its traditional uses and to support its application and development for new drug development.

METHODOLOGY

Scientific information of S. cuneata was retrieved from the online bibliographic databases, including Web of Science, Google Scholar, PubMed, Springer Link, the Wiley online library, SciFinder, Baidu Scholar, China national knowledge infrastructure (CNKI) and WANFANG DATA (up to March 2020). We also search doctoral dissertations, master dissertations conference papers and published books. The keywords were used: "Sargentodoxa", "Da Xue Teng", "Hong Teng", "Xue Teng", "secondary metabolites", "chemical components", "biological activity", "pharmacology", "traditional uses".

OBSERVATIONS AND RESULTS

S. cuneata is utilized as valuable herbal medicines to treat various diseases in China. Over 110 chemical constituents have been isolated and identified from the stem of S. cuneata, including phenolic acids, phenolic glycosides, lignans, flavones, triterpenoids and other compounds. The extract and compounds of S. cuneata have a wide spectrum of pharmacological activities, including antitumor, anti-inflammatory, antioxidant, antimicrobial, anti-sepsis and anti-arthritis effects, as well as protective activity against cerebrovascular diseases.

CONCLUSION

S. cuneata has a rich legacy for the treatment of many diseases, especially arthritis and sepsis, which is reinforced by current investigations. However, the present studies about bioactive chemical constituents and detail pharmacological mechanisms of S. cuneata were insufficient. Further studies should focus on these aspects in relation to its clinical applications. This review has systematically summarized the traditional uses, phytochemical constituents and pharmacological effects of S. cuneata, providing references for the therapeutic potential of new drug development.

In vivo the antioxidative extract of Averrhoa carambola Linn. leaves induced apoptosis in Ehrilch ascites carcinoma by modulating p53 expression

This study was designed to evaluate the antioxidant activity of methanol extract of Averrhoa carambolla Linn. leaves (MELA) using DPPH· and ABTS·+ free radical scavenging assays whereas its antineoplastic effect against Ehrlich ascites carcinoma (EAC) was assed using viable cell count, life span, body weight gain and hematological parameters of experimental mice. Results showed that rich phenolic and flavonoid content of MELA had moderate dose dependent free radical scavenging activity (IC50: 62.0 μg/mL for DPPH· and 6.0 μg/mL for ABTS·+). In vivo antineoplastic assay, MELA significantly (P < 0.05) decreased viable cells and body weight gain, increased the survival time and restored altered hematological profiles of cancer cell bearing mice. Fluorescence microscopic view of EAC cells derived from MELA-treated group showed apoptotic characteristics and this observation was also supported by overexpression of pro-apoptotic genes coding p53 and Bax proteins in treated cancer cells. The anti-apoptotic genes coding Bcl-2 protein was also absent in treated EAC cells as compared with the control. Moreover, phytochemical profiles of MELA as identified by GC/MS analysis are also consistent with its activities.

Protective effect of DMDD, isolated from the root of Averrhoa carambola L., on high glucose induced EMT in HK-2 cells by inhibiting the TLR4-BAMBI-Smad2/3 signaling pathway

BACKGROUND

Hyperglycemia stimulated epithelial-mesenchymal transition (EMT) plays a critical role in initiating and progressing renal fibrosis in diabetic kidney disease (DKD). It is crucial to explore novel renal protective drugs for the treatment of DKD.

OBJECTIVE

The present study is to confirm our hypothesis and to accumulate the information for the application of DMDD (2-Dodecyl-6-methoxycyclohexa-2,5-diene-1,4-dione) as a novel therapeutic agent to potentially inhibit renal fibrogenesis and EMT in the DKD.

METHODS

High glucose induced renal proximal tubular epithelial cell line (HK-2 cells) was cultured and treated with DMDD. The cell viability and DMDD cytotoxicity were assessed by CCK8. Immunofluorescence was used for detection of TLR4 and downstream protein in normal and high glucose induced HK-2 cells. HK-2 cells were transfected with lentivirus codifying for BAMBI (BMP and activin membrane bound inhibitor) and interfering RNA for determination of the effect of BAMBI over-expression and silencing, respectively. TLR4-BAMBI-Smad2/3 pathway was analyzed by means of RT-PCR and western blot.

RESULTS

A high concentration (60mM) of glucose induced significant EMT process and TLR4 expression was increased obviously in this circumstance. DMDD inhibited high expressions of TLR4 and Smad2/3 in HG induced cells and decreased the expression of BAMBI. In addition, the effects of decreased BAMBI expression and increased Smad2/3 expression in HG cultured cells were reversed in the cells of TAK-242 (TLR4 signaling inhibitor) intervention. BAMBI gene silencing dramatically increased EMT process and the over-expression of BAMBI was opposite in HK-2 cells with HG condition. These observations of EMT were ameliorated when the HK-2 cells were pre-treated with DMDD.

CONCLUSIONS

Our study demonstrates that DMDD treatment improves EMT in the HG induced HK-2 cells. In addition, DMDD significantly inhibits EMT by TLR4-BAMBI-Smad2/3 pathway, which hints that DMDD may be an alternative approach in diabetic renal injury.

Effects of Averrhoa carambola L. (Oxalidaceae) juice mediated on hyperglycemia, hyperlipidemia, and its influence on regulatory protein expression in the injured kidneys of streptozotocin-induced diabetic mice

Recently, many reports have shown that Averrhoa carambola L. (Oxalidaceae) juice (EACJ) could reduce blood glucose in humans. However, its mechanisms have not been well explored; therefore, our study aimed to investigate the beneficial effects of EACJ on hyperglycemia, hyperlipidemia and renal injury in streptozotocin (STZ)-induced diabetic mice. Those mice were injected with STZ via the tail vein (120 mg/kg body weight) and were identified as diabetic mice when the level of blood glucose was ≥ 11.1 mmol/L. Those mice were intragastriced gavage with saline, EACJ (25, 50, 100 g/kg body weight/d) and metformin (320 mg/kg body weight/d) for 21 days. The fasting blood glucose (FBG), free fatty acids (FFA), total cholesterol (TC), triglycerides (TG), Scr (CREA) and blood urea nitrogen (BUN) were significantly decreased, while the sorbitol dehydrogenase (SDH), Cyclic Adenosine monophosphate (cAMP), malondialdehyde (MDA), superoxide dismutase (SOD), and insulin were elevated. Diabetes-dependent alterations in the kidney, such as glomerular hypertrophy, thicken and tubular basement membrane, were improved after 21 days of EACJ treatment. Hyperglycemia, renal formation and the expressions of related proteins such as connective tissue growth factor (CTGF) and transforming growth factor beta 1 (TGF-β1) were markedly decreased by EACJ. These results indicate that EACJ treatment decrease hyperglycemia, hyperlipidemia and inhibit the progression of diabetic nephropathy (DN), which may be linked to regulating several pharmacological targets for treating or preventing DN.

Screening and identifying antioxidants from Oplopanax elatus using 2,2'-diphenyl-1-picrylhydrazyl with off-line two-dimensional HPLC coupled with diode array detection and tandem time-of-flight mass spectrometry

The root of Oplopanax elatus (Nakai) Nakai has a well-known history of use for the treatment of diseases such as neurasthenia, cardiovascular disorders, and cancer by the native people in northeast China. It is important to screen and identify the bioactive molecules from its root rapidly. Hereby, an off-line two-dimensional high performance liquid chromatography coupled with diode array detection and tandem time-of-flight mass spectrometry together with 2,2'-diphenyl-1-picrylhydrazyl was established to screen antioxidants from the root of O. elatus. A Waters cyanogen column (150 × 3.9 mm, id, 4 μm) was used for the first dimensional liquid chromatography, while a Hypersil BDS-C18 column (250 × 4.6 mm, id, 5 μm) was installed for the second dimension liquid chromatographic analysis. Twenty-eight compounds had been tentatively identified from the methanol extract of the air-dried root of O. elatus including six polyynes and eight phenolic derivatives were screened with antioxidant activity. The developed method could be expedient for screening and identifying antioxidants from O. elatus.

Melatonin Alleviates Liver Apoptosis in Bile Duct Ligation Young Rats

Bile duct ligation (BDL)-treated rats display cholestasis and liver damages. The potential protective activity of melatonin in young BDL rats in terms of apoptosis, mitochondrial function, and endoplasmic reticulum (ER) homeostasis has not yet been evaluated. Three groups of young male Sprague-Dawley rats were used: one group received laparotomy (Sham), a second group received BDL for two weeks (BDL), and a third group received BDL and intraperitoneal melatonin (100 mg/day) for two weeks (BDL + M). BDL group rats showed liver apoptosis, increased pro-inflamamtory mediators, caspases alterations, anti-apoptotic factors changes, and dysfunction of ER homeostasis. Melatonin effectively reversed apoptosis, mainly through intrinsic pathway and reversed ER stress. In addition, in vitro study showed melatonin exerted its effect mainly through the melatonin 2 receptor (MT2) in HepG2 cells. In conclusion, BDL in young rats caused liver apoptosis. Melatonin rescued the apoptotic changes via the intrinsic pathway, and possibly through the MT2 receptor. Melatonin also reversed ER stress induced by BDL.

Protective Effect of Mangifera indica Linn., Cocos nucifera Linn., and Averrhoa carambola Linn. Extracts against Ultraviolet B-Induced Damage in Human Keratinocytes

This study was aimed at investigating the antioxidant activity of Mangifera indica Linn., Cocos nucifera Linn., and Averrhoa carambola Linn. and their biological effect on human keratinocytes affected by the ultraviolet B (UVB), a major cause of cell damage and skin cancer through induction of DNA damage, production of reactive oxygen species (ROS), and apoptosis. The richest antioxidant activity was found in ethanol fraction of M. indica (21.32 ± 0.66 mg QE/g dry weight), while the lowest one was found in aqueous fractions of M. indica and C. nucifera (1.76 ± 2.10 and 1.65 ± 0.38 mg QE/g dry weight, respectively). Ethanol and aqueous fractions of A. carambola (250 µg/mL) significantly reduced the number of apoptotic cells. The expression of cleaved caspase 3 in UVB-treated group was significantly greater than that in untreated group. Both fractions of A. carambola (50, 100, and 250 µg/mL) significantly decreased the expression of cleaved caspase 3. Regarding the induction of DNA repair, ethanol (100 and 250 µg/mL) and aqueous (50, 100 and 250 µg/mL) fractions of A. carambola significantly decreased the percentage of cyclobutane pyrimidine dimers (CPD). Taken together, our results suggest that both fractions of A. carambola may be potentially developed for dermal applications.

Review of Herbal Traditional Chinese Medicine for the Treatment of Diabetic Nephropathy

Diabetic nephropathy (DN) is the most serious chronic complications of diabetes; 20-40% of diabetic patients develop into end stage renal disease (ESRD). However, exact pathogenesis of DN is not fully clear and we have great difficulties in curing DN; poor treatment of DN led to high chances of mortality worldwide. A lot of western medicines such as ACEI and ARB have been demonstrated to protect renal function of DN but are not enough to delay or retard the progression of DN; therefore, exploring exact and feasible drug is current research hotspot in medicine. Traditional Chinese medicine (TCM) has been widely used to treat and control diabetes and its complications such as DN in a lot of scientific researches, which will give insights into the mechanism of DN, but they are not enough to reveal all the details. In this paper, we summarize the applications of herbal TCM preparations, single herbal TCM, and/or monomers from herbal TCM in the treatment of DN in the recent 10 years, depicting the renal protective effects and the corresponding mechanism, through which we shed light on the renal protective roles of TCM in DN with a particular focus on the molecular basis of the effect and provide a beneficial supplement to the drug therapy for DN.