Antidiabetic Effects of Yam (Dioscorea batatas) and Its Active Constituent, Allantoin, in a Rat Model of Streptozotocin-Induced Diabetes

Alleviation of Menopausal Symptoms by Yam (Dioscorea japonica Thunb.) and Gromwell (Lithospermum erythrorhizon Sieb. Et Zucc.) Extracts in Ovariectomized Mice

SCOPE

The decline in estrogen during menopause contributes to a variety of menopausal symptoms, for which hormone replacement therapy (HRT) has been extensively applied. Regarding side effects and limited effectiveness of HRT for specific individuals, there is a growing interest in safe alternatives such as phytoestrogens which are structurally analogous to estrogens. This study aims to investigate the efficacy of yam and gromwell extracts, rich in bioactive compounds, and the synergistic effect of extracts on symptoms induced by estrogen deficiency in ovariectomized (OVX) mice.

METHODS AND RESULTS

OVX mice receive dietary intervention of either yam, gromwell extract, or their mixture for 14 weeks. Sham-operated mice and E2-injected OVX mice serve as positive controls. Following 14 weeks of oral administration, blood, adipose tissue, vagina, uterus, femurs, and tibias are harvested for further investigation. Consequently, yam and gromwell extracts ameliorate menopausal conditions such as weight gain, glucose intolerance, dyslipidemia, and osteoporosis in estrogen-deficient OVX mice. In addition, the mixture of yam and gromwell extracts synergistically aids in the relief of the indications.

CONCLUSION

These results indicate the potential use of yam and gromwell extracts, as well as their mixture, for the development of healthy functional foods to modulate menopausal symptoms.

A comprehensive in-vitro/in-vivo screening toolbox for the elucidation of glucose homeostasis modulating properties of plant extracts (from roots) and its bioactives

Plant extracts are increasingly recognized for their potential in modulating (postprandial) blood glucose levels. In this context, root extracts are of particular interest due to their high concentrations and often unique spectrum of plant bioactives. To identify new plant species with potential glucose-lowering activity, simple and robust methodologies are often required. For this narrative review, literature was sourced from scientific databases (primarily PubMed) in the period from June 2022 to January 2024. The regulatory targets of glucose homeostasis that could be modulated by bioactive plant compounds were used as search terms, either alone or in combination with the keyword "root extract". As a result, we present a comprehensive methodological toolbox for studying the glucose homeostasis modulating properties of plant extracts and its constituents. The described assays encompass in-vitro investigations involving enzyme inhibition (α-amylase, α-glucosidase, dipeptidyl peptidase 4), assessment of sodium-dependent glucose transporter 1 activity, and evaluation of glucose transporter 4 translocation. Furthermore, we describe a patch-clamp technique to assess the impact of extracts on KATP channels. While validating in-vitro findings in living organisms is imperative, we introduce two screenable in-vivo models (the hen's egg test and Drosophila melanogaster). Given that evaluation of the bioactivity of plant extracts in rodents and humans represents the current gold standard, we include approaches addressing this aspect. In summary, this review offers a systematic guide for screening plant extracts regarding their influence on key regulatory elements of glucose homeostasis, culminating in the assessment of their potential efficacy in-vivo. Moreover, application of the presented toolbox might contribute to further close the knowledge gap on the precise mechanisms of action of plant-derived compounds.

The comparison of the antidiabetic effects of exenatide, empagliflozin, quercetin, and combination of the drugs in type 2 diabetic rats

BACKGROUND

Type 2 diabetes, a metabolic disease that involves extended treatment, is rapidly increasing in humans and animals worldwide.

OBJECTIVES

This study aimed to compare monotherapy and combined therapy of exenatide, empagliflozin, and quercetin in 67 Wistar Albino male rats.

METHODS

The animals were divided into the following seven groups: healthy control, diabetes control, diabetes + sham, diabetes + exenatide (10 μg/kg), diabetes + empagliflozin (50 mg/kg), diabetes + quercetin (50 mg/kg), and diabetes + combination treatment. The treatments were continued for 8 weeks.

RESULTS

At the end of the experiment, glucose and HbA1c levels decreased with all monotherapy treatments and the combination treatments, while insulin levels increased with exenatide and combined treatments. Adiponectin levels increased with empagliflozin, quercetin, and combined treatments, while leptin levels decreased only with combined treatments. All monotherapies caused an increase in total antioxidant levels. Exenatide and quercetin treatments reduced low-density lipoprotein (LDL) levels; therewithal, exenatide and combined treatments increased high-density lipoprotein (HDL) levels. Triglyceride levels decreased in all treatment groups. The homeostatic model assessment for insulin resistance (HOMA-IR) level decreased with the combined treatment; on the contrary, the homeostatic model assessment for β-cell activity (HOMA-β) level increased with empagliflozin, exenatide, and combined treatments.

CONCLUSION

In conclusion, the antidiabetic effects of exenatide were more pronounced than empagliflozin and quercetin, however, the combined treatment had better antidiabetic and antihyperlipidemic effects than monotherapies. Quercetin could be a supportive or food supplement antidiabetic agent. The exenatide treatment can be recommended for monotherapy in type 2 patients, and the combination of empagliflozin, exenatide, and quercetin may be effective in diabetic patients who need combined therapy.

Specific transcription factors Ascl1 and Lhx6 attenuate diabetic neuropathic pain by modulating spinal neuroinflammation and microglial activation in mice

Gamma-aminobutyric acid (GABA) neuronal system-related transcription factors (TFs) play a critical role in GABA production, and GABA modulates diabetic neuropathic pain (DNP). The present study investigated the therapeutic effects of intrathecal delivery of two TFs achaete-scute homolog 1 (Ascl1) and LIM homeobox protein 6 (Lhx6) in a mouse model of DNP and elucidated their underlying mechanisms. GABA-related specific TFs, including Ascl1, Lhx6, distal-less homeobox 1, distal-less homeobox 5, the Nkx2.1 homeobox gene, and the Nkx2.2 homeobox gene, were investigated under normal and diabetic conditions. Among these, the expression of Ascl1 and Lhx6 was significantly downregulated in mice with diabetes. Therefore, a single intrathecal injection of combined lenti-Ascl1/Lhx6 was performed. Intrathecal delivery of lenti-Ascl1/Lhx6 significantly relieved mechanical allodynia and heat hyperalgesia in mice with DNP. Ascl1/Lhx6 delivery also reduced microglial activation, decreased the levels of pro-inflammatory cytokines including tumor necrosis factor-α and interleukin (IL)-1β, increased the levels of anti-inflammatory cytokines including IL-4, IL-10, and IL-13, and reduced the activation of p38, c-Jun N-terminal kinase, and NF-κB in the spinal cord of mice with DNP, thereby reducing DNP. The results of this study suggest that intrathecal Ascl1/Lhx6 delivery attenuates DNP via upregulating spinal GABA neuronal function and inducing anti-inflammatory effects.

Yam Gruel alone and in combination with metformin regulates hepatic lipid metabolism disorders in a diabetic rat model by activating the AMPK/ACC/CPT-1 pathway

BACKGROUND

As independent and correctable risk factors, disturbances in lipid metabolism are significantly associated with type 2 diabetes mellitus (T2DM). This research investigated the mechanism underlying the lipid-regulating effects of Yam Gruel in diabetic rats.

METHODS

First, rats in the control group were given a normal diet, and a diabetic rat model was established via the consumption of a diet that was rich in both fat and sugar for six weeks followed by the intraperitoneal injection of streptozotocin (STZ). After the model was established, the rats were divided into five distinct groups: the control group, model group, Yam Gruel (SYZ) group, metformin (MET) group, and combined group; each treatment was administered for six weeks. The fasting blood glucose (FBG), body and liver weights as well as liver index of the rats were determined. Total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), aspartic acid transaminase (AST), alanine aminotransferase (ALT), and nonesterified fatty acid (NEFA) levels were measured. Oil Red O staining was used to assess hepatic steatosis. In addition, the levels of Phospho-acetyl-CoA carboxylase (p-ACC), acetyl coenzyme A carboxylase (ACC), AMP-activated protein kinase (AMPK), Phospho-AMPK (p-AMPK), carnitine palmitoyl transferase I (CPT-1), and Malonyl-CoA decarboxylase (MLYCD) in liver tissues were measured by real-time PCR (q-PCR) and western blotting.

RESULTS

After 6 weeks of treatment, Yam Gruel alone or in combination with metformin significantly reduced FBG level, liver weight and index. The concentrations of lipid indices (TG, TC, NEFA, and LDL-C), the levels of liver function indices (ALT and AST) and the degree of hepatic steatosis was improved in diabetic rats that were treated with Yam Gruel with or without metformin. Furthermore, Yam Gruel increased the protein levels of p-ACC/ACC, p-AMPK/AMPK, MLYCD, and CPT-1, which was consistent with the observed changes in gene expression. Additionally, the combination of these two agents was significantly more effective in upregulating the expression of AMPK pathway-related genes and proteins.

CONCLUSIONS

These results demonstrated that Yam Gruel may be a potential diet therapy for improving lipid metabolism in T2DM patients and that it may exert its effects via AMPK/ACC/CPT-1 pathway activation. In some respects, the combination of Yam Gruel and metformin exerted more benefits effects than Yam Gruel alone.

Can Polyherbal Medicine be used for the Treatment of Diabetes? - A Review of Historical Classics, Research Evidence and Current Prevention Programs

Diabetes mellitus (DM), a chronic medical condition, has attained a global pandemic status over the last few decades affecting millions of people. Despite a variety of synthetic drugs available in the market, the use of herbal medicines for managing diabetes is gaining importance because of being comparatively safer. This article reviews the result of a substantial literature search on polyherbal formulations (PHFs) developed and evaluated with potential for DM. The accumulated data in the literature allowed us to enlist 76PHFs consisting of different parts of 147 plant species belonging to 58 botanical families. The documented plant species are laden with bioactive components with anti-diabetic properties and thus draw attention. The most favoured ingredient for PHFs was leaves of Gymnema sylvestre and seeds of Trigonella foenum-graecum used in 27 and 22 formulations, respectively. Apart from herbs, shilajit (exudates from high mountain rocks) formed an important component of 9 PHFs, whereas calcined Mytilus margaritiferus and goat pancreas were used in Dolabi, the most commonly used tablet form of PHF in Indian markets. The healing properties of PHFs against diabetes have been examined in both pre-clinical studies and clinical trials. However, the mechanism(s) of action of PHFs are still unclear and considered the pitfalls inherent in understanding the benefits of PHFs. From the information available based on experimental systems, it could be concluded that plant-derived medicines will have a considerable role to play in the control of diabetes provided the challenges related to their bioavailability, bioefficacy, optimal dose, lack of characterization, ambiguous mechanism of action, and clinical efficiency are addressed.

Yao-Shan of traditional Chinese medicine: an old story for metabolic health

Type 2 diabetes mellitus, nonalcoholic fatty liver disease (NAFLD), cardio-cerebrovascular diseases (CCVDs), hyperuricemia and gout, and metabolic-related sexual dysfunction are metabolic diseases that affect human health in modern society. Scientists have made great efforts to investigate metabolic diseases using cell models in vitro or animal models in the past. However, the findings from cells or animals are difficult to translate into clinical applications due to factors such as the in vitro and in vivo differences; the differences in anatomy, physiology, and genetics between humans and animals; and the differences in microbiome-host interaction. The Chinese have extensively used the medicated diet of traditional Chinese medicine (TCM) (also named as Yao-Shan of TCM, Chinese Yao-Shan et al.) to maintain or improve cardiometabolic health for more than 2,200 years. These ancient classic diets of TCM are essential summaries of long-term life and clinical practices. Over the past 5 years, our group has made every effort to collect and sort out the classic Yao-Shan of TCM from the ancient TCM literature since Spring and Autumn and Warring States Period, especially these are involved in the prevention and treatment of metabolic diseases, such as diabetes, NAFLD, CCVDs, hyperuricemia and gout, and sexual dysfunction. Here, we summarized and discussed the classic Yao-Shan of TCM for metabolic diseases according to the time recorded in the ancient literature, and revised the Latin names of the raw materials in these Yao-Shan of TCM. Moreover, the modern medicine evidences of some Yao-Shan of TCM on metabolic diseases have also been summarized and emphasized in here. However, the exact composition (in terms of ratios), preparation process, and dosage of many Yao-Shan are not standardized, and their main active ingredients are vague. Uncovering the mystery of Yao-Shan of TCM through modern biological and chemical strategies will help us open a door, which is ancient but now looks new, to modulate metabolic homeostasis and diseases.

Biogenic Carbon Quantum Dots as a Neoteric Inducer in the Game of Directing Chondrogenesis

The journey into the field of stem cell biology has been an endeavor of paramount advancement in biomedicine, establishing new horizons in the avenue of materiobiology. The creative drive of the scientific community focuses on ameliorating the utilization of stem cells, which is currently untapped on a large scale. With similar motivation, we present a nascent strategy of maneuvering biogenic carbon quantum dots (CQDs) to eclipse the toxic hurdles of chemical synthesis of carbon allotropes to serve as a biocompatible trident in stem cell biology employing a three-prong action of stem cell differentiation, imaging, and migration. The derivation of CQDs from garlic peels as a biogenic precursor abets in realizing the optophysical features of CQDs to image mesenchymal stem cells without hampering the biological systems with cytotoxicity. We report the versatility of biogenic CQDs to generate reactive oxygen species (ROS) to robustly influence stem cell migration and concomitantly chondrocyte differentiation from human Wharton's jelly mesenchymal stem cells (hWJ-MSCs). This was orchestrated without the use of chondrogenic induction factors, which was confirmed from the expression of chondrogenic markers (Col II, Col X, ACAN). Even the collagen content of cells incubated with CQDs was quite comparable with that of chondrocyte-induced cells. Thus, we empirically propose garlic peel-derived CQDs as a tangible advancement in stem cell biology from a materiobiological frame of reference to hone significant development in this arena.

Effect of isgin (Rheum ribes L.) on biochemical parameters, antioxidant activity and DNA damage in rats with obesity induced with high-calorie diet

The present study was designed to investigate the effects of Rheum ribes L. plant root extracts on DNA damage, biochemical and antioxidant parameters in rats with experimental obesity induced with a high-calorie diet. The study groups were divided as "normal control(NC)", "obese control(OC)", "obese + Rheum ribes(OR1)(200 mg/kg)" and "obese + Rheum ribes (OR2)(400 mg/kg)". At the end of the application, rats were sacrificed and blood and tissue samples were obtained. According to the results obtained, the marker of DNA damage in tissues of 8-OHdG was determined to be significantly reduced in brain tissue of the OR1 and OR2 groups compared to the NC group. However, fluctuations were identified in the MDA activity, antioxidant defense system elements and serum biomarkers in tissues. In conclusion, Rheum ribes plant root extract ensured improvements in DNA damage in brain tissues and MDA levels and showed positive effects on antioxidant parameter activities in different tissues.

Chitosan Nanogel with Mixed Food Plants and Its Relation to Blood Glucose in Type 2 Diabetes: A Systematic and Meta-Analysis Review of Observational Studies

This systematic review with metanalysis evaluated and analyzed the beneficial effects of certain plants food in type 2 diabetes (T2D) when consumed alone or in combination with chitosan. The main objective of the paper was to examine the relation of chitosan nanogel and mixed food plant (MFP) to control T2D. The databases included Medline, Scopus, PubMed, as well as Cochrane available between the month of January 1990 to January 2021. The eligibility criteria for selecting studies were case-controlled studies that included unripe plantain, bitter yam, okra, and chitosan either used-alone or in combination with non-specified food plants (NSFP). Two-fold autonomous critics retrieved the information required and evaluated the risk of bias of involved studies. Random-effect meta-analyses on blood glucose controls, were performed. Results of 18 studies included: seven that examined unripe plantains, one bitter yam, two okras, and eight chitosan, found regarding the decrease in blood glucose level. Meta-analysis of the results found a large proportion of I² values for all studies (98%), meaning heterogeneity. As a consequence, the combined effect sizes were not useful. Instead, prediction interval (PI) was used (mean difference 4.4 mg/dL, 95% PI -6.65 to 15.50 and mean difference 3.4 mg/dL, 95% PI -23.65 to 30.50) rather than the estimate of its confidence interval (CI). These studies were at 50% high risk of bias and 50% low risk of bias and there was judged to be an unclear risk of bias due to the insufficient information from the included study protocol (moderately low). The intervention lasted between three and 84 days, indicating potency and effectiveness of the intervention at both short and long durations. Due to the moderately low quality of the studies, the findings were cautiously interpreted. In conclusion, the current evidence available from the study does support the relation of chitosan with mixed unripe plantain, bitter yam and okra for the management of T2D. Further high-quality case-controlled animal studies are required to substantiate if indeed chitosan nanogel should be cross-linked with the specified food plant (SFP) for the management T2D.

Investigation of Natural Compounds for Therapeutic Potential in Streptozotocin-induced Diabetic Neuroinflammation and Neuropathic Pain

Diabetic neuropathy (DN) is a serious microvascular complication of diabetes mellitus (DM) that impacts the nervous system. Several risk factors are involved in the progression and maintenance of DN-associated pain, such as higher expression of various inflammatory mediators, e.g., tumor necrotic factor-alpha (TNF-α), nuclear factor-kappa B (NF-κB), and cyclo-oxygenase-2 (COX-2). The present research explores the neuroprotective potential of natural isolates, including berbamine, bergapten, and carveol, on the DM-induced neuroinflammation and neurodegeneration that cause neuropathic pain. The study utilized computerized techniques, including computational analysis (a docking assay and a molecular dynamic simulation) before moving to in vivo protocols. Diabetic neuropathy was induced by intraperitonial injection (IP) of streptozotocin (65 mg/kg), and the animal subjects (rats) were kept for 4 weeks for the development of DN. Once diabetic neuropathy was confirmed, the subjects were treated with berbamine, bergapten, and carveol until the sixth week (i.e., 2 weeks of treatment). At the sixth week, the rats were sacrificed, and the sciatic nerve and spinal cord of each was collected for further molecular investigation. Docking and a molecular dynamic simulation (MDS) delivered the information that the natural compounds (berbamine, bergapten, and carveol) were interacting with the selected target protein (i.e., mitogen-activated protein kinase). After IP, it was found that berbamine, bergapten, and carveol had ameliorated mechanical allodynia and thermal hyperalgesia by the 28th day of the study (2 weeks after treatment) without affecting blood glucose levels. Berbamine, bergapten, and carveol markedly elevated the levels of glutathione (GSH) and glutathione s-transferase (GST), in both the sciatic nerve and spinal cord, and also reduced lipid peroxidase (LPO) and nitric oxide (NO). The abovementioned natural isolates reduced pathologic alterations provoked through DN, a finding confirmed through histopathological assays (hematoxylin and eosin staining and immuno-histochemical analysis). Treatment down regulated higher expressions of the inflammatory mediatorcyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), and nuclear factor kappa B (NF-κB), as confirmed by ELISA and polymerase chain reaction (PCR). The outcomes of berbamine, bergapten, and carveol are compared with those of pregabalin as a positive control group. Compared to pregabalin, treatment with the aforementioned three natural compounds improved nociception and reduced hyperalgesic effects, and consequently reduced pain perception and inflammation. Our results suggest the mechanism for the neuro-protective impact of berbamine, bergapten, and carveol might possibly be arbitrated via COX-2, TNF-α, and NF-κB, and regulated by mitogen-activated protein kinase, ultimately ameliorating STZ-provoked, DM-induced neuroinflammation and neurodegeneration, and associated neuropathic pain.

Communication in non-communicable diseases (NCDs) and role of immunomodulatory nutraceuticals in their management

Conveyance of pathogens between organisms causes communicable diseases. On the other hand, a non-communicable disease (NCD) was always thought to have no causative transmissible infective agents. Today, this clear distinction is increasingly getting blurred and NCDs are found to be associated with some transmissible components. The human microbiota carries a congregation of microbes, the majority and the most widely studied being bacteria in the gut. The adult human gut harbors ginormous inhabitant microbes, and the microbiome accommodates 150-fold more genes than the host genome. Microbial communities share a mutually beneficial relationship with the host, especially with respect to host physiology including digestion, immune responses, and metabolism. This review delineates the connection between environmental factors such as infections leading to gut dysbiosis and NCDs and explores the evidence regarding possible causal link between them. We also discuss the evidence regarding the value of appropriate therapeutic immunomodulatory nutritional interventions to reduce the development of such diseases. We behold such immunomodulatory effects have the potential to influence in various NCDs and restore homeostasis. We believe that the beginning of the era of microbiota-oriented personalized treatment modalities is not far away.

Structures and Anti-Inflammatory Evaluation of Phenylpropanoid Derivatives from the Aerial Parts of Dioscorea polystachya

Seven undescribed phenylpropanoid constituents, including three new bibenzyl derivatives (1–3) along with four new benzofuran stilbene derivatives (4–7), were isolated from the aerial parts of Dioscorea polystachya. The structures of these compounds were elucidated using a combination of spectroscopic analyses, including UV, IR, HRESIMS, 1D, and 2D NMR. Further, all the compounds were evaluated on the anti-inflammatory activity for their inhibition of nitric oxide (NO) production by RAW 264.7 macrophages cells, and some of them (1–3 and 6) displayed inhibitory activity with IC₅₀ values in the range of 9.3–32.3 μM. Moreover, compound 3 decreased the expression of iNOS in Western blot analysis, suggesting compound 3 is mediated via the suppression of an LPS-induced NF-κB inflammasome pathway.

Development and Validation of Quantitative Analysis Method for Phenanthrenes in Peels of the Dioscorea Genus

Phenanthrenes are bioactive phenolic compounds found in genus Dioscorea, in which they are distributed more in peel than in flesh. Recent studies on phenanthrenes from Dioscorea sp. peels have revealed the potential for valuable biomaterials. Herein, an analytical method using high-performance liquid chromatography (HPLC) for quantitation of bioactive phenanthrenes was developed and validated. The calibration curves were obtained using the phenanthrenes (1-3) previously isolated from Dioscorea batatas concentrations in the range of 0.625-20.00 μg/ml with a satisfactory coefficient of determination (R2) of 0.999. The limit of detection (LOD) and the limit of quantification (LOQ) values of the isolated phenanthrenes ranged from 0.78-0.89 and 2.38-2.71 μg/ml, respectively. The intraday and interday precision ranged from 0.25-7.58%. The recoveries of the isolated phenanthrenes were from 95 to 100% at concentrations of 1.25, 2.5, and 5.0 μg/ml. Additionally, phenanthrenes (1-3) were found in all investigated peel extracts. Hence, the developed method was encouraging for the quantitative analysis of phenanthrenes in genus Dioscorea.

Could consumption of yam (Dioscorea) or its extract be beneficial in controlling glycaemia: a systematic review

Yam (Dioscorea spp.) and its associated extracts have been shown to possess a variety of biological activities and identified as beneficial in the control of glycaemia in patients with type II diabetes mellitus (T2DM). The objective was to conduct a systematic search of the literature to investigate whether yam and its extract can improve glycaemia and whether the consumption of yam could be beneficial for managing T2DM. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and the Population, Invention, Comparison and Outcome framework, three databases (PubMed, Scopus and Web of Science) were searched using a key term strategy. Strict inclusion criteria were employed to identify all relevant and available studies. The quality of these studies was assessed using SYRCLE's Risk of Bias tool. Ten studies were included, and all studies consisted of findings from rodent models of diabetes, including animals consuming high fat diets or genetic models of diabetes. All ten studies showed that the consumption of yam and/or its extracts (containing dioscin, dioscorin, diosgenin, DA-9801/02 or Chinese yam polysaccharides) improved glycaemia. These included improvements in fasting blood glucose and reductions in glucose and increase in insulin levels following a glucose tolerance test. Furthermore, significant changes in body weight and adiposity were observed in nine studies, these included improvements in lipid biomarkers in four and reductions in inflammatory markers in one. The current work indicates that the consumption of yam or its extracts can be beneficial for improving blood glucose; however, the molecular mechanism for these effects remains largely unknown. Future trials on human subjects are warranted.

Metabolomic Characteristics of Liver and Cecum Contents in High-Fat-Diet-Induced Obese Mice Intervened with Lactobacillus plantarum FRT10

Obesity has become a major social problem related to health and quality of life. Our previous work demonstrated that Lactobacillus plantarum FRT10 alleviated obesity in high-fat diet (HFD)-fed mice by alleviating gut dysbiosis. However, the underlying functions of FRT10 in regulating liver and cecum contents metabolism remain unknown. Liver and cecum contents metabonomics combined with pathway analysis based on ultraperformance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UHPLC-Q-TOF/MS) were performed to evaluate the alterations of metabolic profiles between obese control mice and obese mice in FRT10-treated groups. The orthogonal partial least squares discriminant analysis (OPLS-DA) score plots showed that there were significant differences in cecum contents and liver markers between experimental groups. In total, 26 potential biomarkers were identified in the liver and 15 in cecum contents that could explain the effect of FRT10 addition in HFD-fed mice. In addition, gut–liver axis analysis indicated that there was a strong correlation between cecum contents metabolites and hepatic metabolites. The mechanism of FRT10 against obesity might be related to the alterations in glycerophospholipid metabolism, primary bile acid biosynthesis, amino metabolism, and purine and pyrimidine metabolism. Studies on these metabolites could help us better understand the role of FRT10 in obesity induced by HFD.

Dioscorea spp.: Comprehensive Review of Antioxidant Properties and Their Relation to Phytochemicals and Health Benefits

Dioscorea, consisting of over 600 species, is the most important genus in the Dioscoreaceae family; however, the practically used plants, which are commonly called yam, are restricted to a remarkably smaller number of species. Numerous studies have reported the high nutritional value of yam, particularly as an alternative source of starch and some important micronutrients. Several Dioscorea species are widely used for various medicinal purposes as well. In many studies, the bioactivities and health benefits of Dioscorea extracts and other preparations have been related to the presence of phytochemicals, which possess antioxidant properties; they are related mainly to radical-scavenging capacity in chemical assays and positive effects on the endogenous antioxidant system in cell-based and in vivo assays. Considering the increasing number of publications on this topic and the absence of comprehensive and focused review papers on antioxidant potential, this article summarizes the results of studies on the antioxidant properties of Dioscorea spp. and their relation to phytochemicals and health benefits. A comprehensive survey of the published articles has revealed that the majority of studies have been performed with plant tubers (rhizomes, roots), while reports on leaves are rather scarce. In general, leaf extracts demonstrated stronger antioxidant potential than tuber preparations. This may be related to the differences in phytochemical composition: saponins, phenanthrenes and, for some pigment-rich species (purple yams), anthocyanins are important constituents in tubers, while phenolic acids and flavonoids are characteristic phytochemicals in the leaves. The review may assist in explaining ethnopharmacological knowledge on the health benefits of Dioscorea plants and their preparations; moreover, it may foster further studies of poorly investigated species, as well as their wider application in developing new functional foods and nutraceuticals.

Investigation of healing effects of lemon (Citrus limonum) seeds lyophilized extracts on experimental diabetic rats

In this study, the effects of lemon seed lyophilised extract (LSLE) were investigated on the diabetic rats. Groups were conducted as normal control (NC), diabetic control (DC), diabetic + 20 mg acarbose/kg bw (DAC)), diabetic + 100 mg LSLE/kg bw (DLSLE1), diabetic + 200 LSLE mg/kg bw (DLSLE2) and diabetic + 400 LSLE mg/kg bw (DLSLE4). The protective and antioxsidant effects of LSLE on experimental diabetes complications were evaluated by measuring hepatic and renal damage biomarkers (HRDBs), antioxidant defence system constituents (ADSCs), diabetes biomarkers and MDA content in tissues of diabetic rats. Glucose, HRDBs, HbA1c, lipid profile (LP) levels increased in DC compared to NC whereas these parameters of the supplementation groups showed a significant decreas compared to DC. Also, it was determined an increase MDA content and fluctuate ADSCs in the DC tissues whereas the LSLE restored the parameters towards to the NC. It can be said that LSLE is may have healings effects against diabetic complications.

Allantoin from Valuable Romanian Animal and Plant Sources with Promising Anti-Inflammatory Activity as a Nutricosmetic Ingredient

Helix aspersa (HA), Helix pomatia (HP) and Symphytum officinale are common organisms in Romania’s biosphere, widely known for their allantoin content and their therapeutic properties. Herein, the allantoin was separated and quantified from the aqueous extracts of Romanian comfrey root and the secretions of HA and HP snails. This study also focused on determining the antioxidant and anti-inflammatory activities of these Romanian allantoin-rich samples. The plant extracts were obtained through two methods: ultrasonic extraction and enzymatic ultrasonic extraction. A microplate method was used for the quantitative determination of allantoin content. The antioxidant activity was measured by using the DPPH radical scavenging method. The antioxidant capacity of the samples was studied in order to observe the type of interactions generated by the chemical complex present in their composition. High concentrations of allantoin were obtained by enzymatic ultrasonic extraction method (EUE—102 ± 0.74 μg/mL), and also in the water-soluble fraction of the snail secretion (FS1—22.051 μg/mL). The antioxidant screening suggests that Symphytum officinale and snail mucus extracts could be used as promising natural substitutes for synthetic antioxidants in products used for therapeutic purposes. The evaluation of anti-inflammatory activity was also investigated, allantoin-rich samples showing a promising action (FS1—81.87 ± 2.34%). In future, the inclusion of allantoin-rich extracts in various novel pharmaceutical forms for new therapeutic applications could be achieved. The study will continue with the formulation of a nutricosmetic product with snail mucus and Symphytum officinale extract as principal bioactive ingredients.

Allantoin, a purine metabolite, enhances peripheral nerve regeneration following sciatic nerve injury in rats: A stereological and immunohistochemical study

AIM

Following peripheral nerve injury, in addition to axonal and myelin degeneration, a sharp increase is observed in cell numbers, especially Schwann cells, in the distal part of the injury. This study investigated the effect of allantoin, involved in purine catabolism, on the reactions occurring in the lesion area.

MATERIAL AND METHOD

An experimental sciatic nerve injury model was established with the application of pressure at 50 Newtons for 5 s to the right sciatic nerves of experimental animals following visualization with the help of pliers. Allantoin was administered to the test groups via the intraperitoneal (i.p.) route (10 mg/kg), at the same time every day for 30 days. The animals were sacrificed at the end of 30 days, following electromyography and Sciatic Function Index tests. Myelinated/unmyelinated axon numbers were evaluated stereologically. Myelin sheath thickness, axon diameter, mitotic activity, and functional improvement in muscles in this peripheral nerve degeneration model were investigated. The test results were then subjected to statistical analysis.

RESULTS

Allantoin was observed to exhibit curative effects in terms of function, although stereological tests revealed no morphological differences.

CONCLUSION

The i.p. administration of allantoin may have a beneficial effect on nerve healing.

Evaluation of the in vitro and in vivo genotoxicity of a Dioscorea Rhizome water extract

Dioscorea Rhizome is commonly used in traditional herbal medicines for the treatment of diabetes, hyperthyroidism, liver damage, neuropathy, and asthma. Here, we investigated the genotoxicity potential of D. Rhizome water extract (DRWE) using three standard battery systems in accordance with the test guidelines of the Organisation for Economic Cooperation and Development and Ministry of Food and Drug Safety as well as the principles of Good Laboratory Practice. A bacterial reverse mutation test (Ames test) was performed using the direct plate incorporation method in the presence or absence of a metabolic activation system (S9 mixture). The tester strains used included four histidine auxotrophic strains of Salmonella typhimurium, TA100, TA1535, TA98, and TA1537, along with a tryptophan auxotrophic strain of Escherichia coli, WP2 uvrA. An in vitro chromosome aberration test was performed using CHL/IU cells originally derived from the lung of a female Chinese hamster in the presence or absence of the S9 mixture. An in vivo mouse bone marrow micronucleus test was performed using male ICR mice. The micronucleus was confirmed after observation of the micro-nucleated polychromatic. The Ames test showed that DRWE did not induce gene mutations at any dose level in any of the tested strains. Additionally, DRWE did not result in any chromosomal aberrations specified in the in vitro chromosomal aberration and in vivo micronucleus tests. These results showed that DRWE exhibited neither mutagenic nor clastogenic potential in either the in vitro or in vivo test systems.

A 13-week subchronic toxicity study of a Dioscorea Rhizome water extract in rats

Dioscorea Rhizome is widely used as a traditional herbal medicine to treat asthma, diarrhea, cough, bronchitis, spermatorrhea, leukorrhea, and rheumatoid arthritis. This study investigated the potential subchronic toxicity of a D. Rhizome water extract (DRWE) after repeated oral administration at 0, 800, 2000, and 5000 mg/kg/day in rats for 13 weeks. During the study period, clinical signs, mortality, body weight, food consumption, water consumption, urinalysis, ophthalmoscopy, hematology, serum biochemistry, gross pathology, organ weights, and histopathology were examined. The 13-week repeated oral administration of DRWE to rats resulted in an increased incidence of zona glomerulosa hypertrophy and hyperplasia in the adrenal gland at dose levels of ≥2000 mg/kg/day in both sexes. However, these findings are considered as non-adverse adaptive changes because of minimal histological changes in the lesions, which were not accompanied by any corresponding alterations in serum electrolytes and adrenal gland weight. No treatment-related adverse effects on clinical signs, body weight, food and water consumption, ophthalmic examination, urinalysis, hematology, serum biochemistry, necropsy findings, and organ weights were observed at any dose tested. Under the present experimental conditions, the no-observed-adverse-effect level of the DRWE was considered to be 5000 mg/kg/day in both sexes, and no target organs were identified.

Hypoglycemic and hypolipidemic effects of two mangrove plants in a streptozotocin-induced animal model of diabetes

Objective:

This study aims at evaluating the anti-diabetic, hypolipidemic, and pancreatic histopathological changes of Rhizophora mucronata and Avicennia marina.

Materials and Methods:

The experimental rats were divided into eight groups (n = 15 each). Streptozotocin was used to induce diabetes. Daily oral administration of an aqueous extract from the leaves of R. mucronata and A. marina at 400 mg/kg BW, and a mixture of the two extracts for 6 weeks was assessed. The measurements of serum glucose, insulin, and lipid profile were carried out. Pancreatic specimens were collected from all groups and processed for pathological studies.

Results:

The study revealed that the plant extracts restored the levels of diabetic markers and lipid profiles of diabetic rats, with no significant changes in non-diabetic ones. The extract of R. mucronata exhibited more promising anti-diabetic and hypolipidemic effects than A. marina singly or combined.

Conclusion:

Leaf extracts from R. mucronata, singly or combined, and A. marina, induced a potent anti-diabetic and hypolipidemic potential in diabetic rats.

Effects of a rhizome aqueous extract of Dioscorea batatas and its bioactive compound, allantoin in high fat diet and streptozotocin-induced diabetic mice and the regulation of liver, pancreas and skeletal muscle dysfunction

ETHNOPHARMACOLOGICAL RELEVANCE

Dysfunction of glucose metabolism is associated with the occurrence of metabolic syndromes, including type 2 diabetes mellitus (T2DM). In this study, we investigated the anti-diabetic effects of yam aqueous extract and allantoin in high-fat-diet (HFD) and streptozotocin (STZ)-induced diabetic mice and the mechanism of action on the dysfunction of the liver, pancreas, and skeletal muscle.

MATERIALS AND METHODS

Male C57BL/6 mice were induced into a diabetic condition by HFD for 16 weeks and a single injection of STZ (120 mg/kg) and then orally administered yam aqueous extract (500 and 1000 mg/kg) or allantoin (20 and 50 mg/kg) once daily for 4 weeks. The changes in physiological parameters, serological parameters, and morphology of tissues were investigated. The expression levels of antioxidant enzymes, biogenetic proteins, and myogenetic proteins were determined in the liver, pancreas and skeletal muscle tissues of mice.

RESULTS

The administration of yam aqueous extract and allantoin at high doses in HFD/STZ-induced diabetic mice compared with the control group significantly decreased the increase in body weight, caloric intake, and water intake. Yam aqueous extract and allantoin significantly decreased high glucose and leptin, total cholesterol, triglyceride, low-density lipoprotein-cholesterol, aspartate transaminase, alanine aminotransferase levels and increased insulin and albumin levels in the plasma of mice. Yam aqueous extract and allantoin inhibited the structural damage of the liver with regard to fat accumulation, the pancreas with atrophy of Langerhans' islets, and skeletal muscle with regard to atrophy and significantly increased the expression of antioxidant enzymes and mitochondria-mediated biogenetic factors in the liver, pancreas, and muscle tissues. In addition, Yam aqueous extract and allantoin significantly increased the expression of myogenetic proteins in skeletal muscle tissues.

CONCLUSION

Our results indicated that Yam aqueous extract and allantoin improve diabetic symptoms through the regulation of oxidation and glucose imbalance in liver, pancreas, and skeletal muscle tissues in mice. These findings suggest that Yam aqueous extract and allantoin can be used as antidiabetic factors in supplementary foods and medications for T2DM patients.

Evaluation of the alpha-amylase inhibitory activity of Nepalese medicinal plants used in the treatment of diabetes mellitus

Background

α-Amylase catalyses the hydrolysis of starch and ultimately producing glucose. Controlling the catalytic activity of this enzyme reduces glucose production in the postprandial stage, which could be a therapeutic benefit for people with diabetes. This study was conducted to evaluate α-amylase inhibition for utilizing the crude extracts of some medicinal plants traditionally used in Nepal for the treatment of diabetes and its related complications.

Methods

Microtiter plate approach has been used to assess inhibitory activities of in vitro α-amylase of methanolic extracts of thirty-two medicinal plants. A starch tolerance test was used in rats to investigate the in vivo study of the methanolic extract concerning glibenclamide as the positive control.

Results

Acacia catechu, Dioscorea bulbifera, and Swertia chirata exhibited inhibitory activity against α-amylase and with IC50 values; 49.9, 296.1, and 413.5 μg/mL, respectively. Kinetics study revealed that all the extracts displayed a mixed type of inhibition pattern, with Ki values ranging from 26.6–204.2 μg/mL. Free radical scavenging activity was again re-examined and found prominent in extracts of A. catechu. Likewise, A. catechu and S. chirata showed significant reduction of blood glucose concentration up to 30 min after oral dose of 250 mg/kg (F (4, 20) = 4.1, p = .048), and (F (4, 20) = 4.1, p = .036), respectively.

Conclusions

Enzymatic assay for α-amylase inhibition using extracts was successfully evaluated. Also, the in-vitro and in-vivo study model revealed that medicinal plants could be a potent source of α-amylase inhibition. So, they could serve as potential candidates for future drug development strategies for curing diabetes with minimal or no adverse side effects.

Anti-diabetic Effect of Emblica-officinalis (Amla) Against Arsenic Induced Metabolic Disorder in Mice

Chronic exposure to arsenic through drinking water and occupational exposure has been found to be associated with the diabetic symptoms. Earlier, we reported that arsenic induced enhanced oxidative stress, inflammation, dislipidemia and hepatotoxicity in mice have been protected by treatment with Emblica officinalis (amla). The present study has therefore been focused to investigate the efficacy of amla in mitigation of arsenic induced hyperglycemia in mice. Arsenic exposure (3 mg/kg b.w./day for 30 days) in mice altered glucose homeostasis and significantly decreases hepatic glucose regulatory enzyme, glucokinase (43%), glucose-6 phosphate dehydrogenase (38%), malic enzyme (60%) and significantly increases the level of glucose-6 phosphates (65%), phosphoenolpyruvate carboxykinase (43%), lactate, (59%) Na+ (6.8%) Cl- (10.4%), anion gap (13.9%) and pancreatic (IL-1β, TNF-α) inflammation markers (52%, 53%) as compared to controls. Arsenic exposure also significantly decreased serum insulin (44%) and c-peptide protein (38%) in mice as compared to controls. Co-administration of arsenic and amla (500 mg/kg b.w./day for 30 days) balanced blood sugar level, hepatic glucose regulatory enzyme (glucokinase, glucose-6 phosphate dehydrogenase, malic enzyme (68%, 37%, 45%) and significantly decreases glucose-6 phosphatase (25%), phosphoenolpyruvate carboxykinase (22%), blood ion concentration and also lactate, Na+, Cl- and anion gap (20%, 4.6%, 6.7%, 5.2%), pancreatic (IL-1β, TNF-α) inflammation marker (21%, 24%) and significantly increased the serum insulin (57%) and c-peptide protein (31%) as compared to those treated with arsenic alone. Results of the present study suggests that the hypoglycemic and antioxidant property of amla could be responsible for its protective efficacy in arsenic induced hyperglycemia.

Systems Pharmacology-Based Strategy to Investigate Pharmacological Mechanisms of Radix Puerariae for Treatment of Hypertension

Hypertension is a clinical cardiovascular syndrome characterized by elevated systemic arterial pressure with or without multiple cardiovascular risk factors. Radix Pueraria (RP) has the effects of anti-myocardial ischemia, anti-arrhythmia, vasodilatation, blood pressure reduction, anti-inflammation, and attenuating insulin resistance. Although RP can be effective for the treatment of hypertension, its active compounds, drug targets, and exact molecular mechanism are still unclear. In this study, systems pharmacology was used to analyze the active compounds, drug target genes, and key pathways of RP in the treatment of hypertension. Thirteen active compounds and related information on RP were obtained from the TCMSP database, and 140 overlapping genes related to hypertension and drugs were obtained from the GeneCards and OMIM databases. A PPI network and a traditional Chinese medicine (TCM) comprehensive network (Drug-Compounds-Genes-Disease network) were constructed, and 2,246 GO terms and 157 pathways were obtained by GO enrichment analysis and KEGG pathway enrichment analysis. Some important active compounds and targets were evaluated by in vitro experiments. This study shows that RP probably acts by influencing the proliferation module, apoptosis module, inflammation module, and others when treating hypertension. This study provides novel insights for researchers to systematically explore the mechanism of action of TCM.

Integrating Chinese and Western medicines reduced the incidence of hepatocellular carcinoma in patients with diabetes mellitus: A Taiwanese population-based cohort study

OBJECTIVES

Much epidemiological evidence links diabetes mellitus (DM) to the development of multiple cancers and, in particular, the development of hepatocellular carcinoma (HCC). The aim of this study was to investigate whether Chinese herbal medicine (CHM) reduces the incidence of HCC in patients receiving Western antidiabetic drugs.

INTERVENTIONS AND MAIN OUTCOME MEASURES

This retrospective cohort study used data from the National Health Insurance Research Database involving 81,105 diabetic patients, including 5122 CHM users and 25,966 non-CHM users. Analyses of treatment effects were adjusted for covariates including gender, age, comorbidities, antidiabetic drugs and liver medications. NodeXL software performed a network analysis to identify the 50 most commonly used CHM herbs and formulas.

RESULTS

In Cox proportional hazards models adjusted for demographic and clinical characteristics, DM patients exposed to adjuvant CHM therapy were significantly less likely to develop HCC compared with non-CHM users (adjusted hazard ratio [aHR] 0.59; 95 % confidence interval [CI], 0.41-0.87; p = 0.01). Kaplan-Meier analysis revealed a lower 10-year cumulative risk of HCC among CHM users compared with non-CHM users. Amongst the 10 individual CHM herbs and herbal formulas most commonly prescribed for DM, the most frequent were Salvia miltiorrhiza (Dan Shen) and Liu Wei Di Huang Wan, respectively.

CONCLUSION

This nationwide retrospective cohort study from Taiwan provides some valuable insights into the prescribing characteristics of CHM treatment in patients with DM. Compared with use of Western antidiabetic medications alone, use of adjuvant CHM effectively reduces the incidence of HCC in patients with DM.

The Effects and Mechanism of Quercetin Dietary Supplementation in Streptozotocin-Induced Hyperglycemic Arbor Acre Broilers

Quercetin, a flavonoid found in fruits and vegetables, is widely distributed as a secondary metabolite in the plant kingdom. Oxidative stress plays a role in the pathogenesis of diabetes mellitus (DM). The present study investigated the effects of quercetin dietary supplementation on streptozotocin- (STZ-) induced hyperglycemic Arbor Acre (AA) broilers by determining the levels of fasting blood glucose (FBG), fasting insulin (FINS), biochemical indicators, oxidative stress markers, inflammatory cytokines content, antioxidant enzymes activities in tissues, and mRNA expression of genes relating to the insulin signaling pathway. Three hundred one-day-old healthy AA broilers were randomly assigned into 5 treatments; A, control healthy broilers; B, STZ-induced broilers; C, STZ-induced broiler dietary supplemented with 0.02% quercetin; D, STZ-induced broiler dietary supplemented with 0.04% quercetin; and E, STZ-induced broiler dietary supplemented with 0.06% quercetin. The results showed that quercetin supplementation relieved the side effects of STZ-induced oxidative stress by changing activities of antioxidant enzymes, decreasing malondialdehyde (MDA) and nitric oxide (NO) levels, activating expression of genes relating to PI3K/PKB signaling pathway that modulate glucose metabolism and reduce oxidative damage, thereby decreasing FBG and increasing FINS levels. These findings suggest that quercetin exhibits a protective effect in STZ-induced hyperglycemic AA broilers via decreasing oxidative stress.

Study on Hypoglycemic Effect of the Drug Pair of Astragalus Radix and Dioscoreae Rhizoma in T2DM Rats by Network Pharmacology and Metabonomics

Type 2 diabetes mellitus (T2DM) is a metabolic disease accompanied by a series of diseases such as diabetic nephropathy. The drug pair (HS) of Astragalus Radix (HQ) and Dioscoreae Rhizoma (SY) was designed by Dr. Shi Jinmo to improve the treatment of T2DM. However, the exact mechanism involved requires further clarification. In this work, 1H-NMR-based metabonomics and network pharmacology were adopted. Metabolic profiling indicated that the metabolic perturbation was reduced after HS treatment. The results found 21 biomarkers. According to the network pharmacology, we found that the regulation of T2DM was primarily associated with 18 active compounds in HS. These active compounds mainly had an effect on 135 targets. Subsequently, combining network pharmacology and metabonomics, we found four target proteins, which indicated that HS has potential hypoglycemic effects through regulating monoamine oxidases B (MAOB), acetyl-CoA carboxylase 1 (ACACA), carbonic anhydrase 2 (CA2), and catalase (CAT). In conclusion, the result showed that these four targets might be the most relevant targets for the treatment of T2DM with HS. This study clarified the mechanism of HS in the treatment of T2DM and also confirmed the feasibility of combining metabonomics and network pharmacology to study the mechanisms of traditional Chinese medicine (TCM). In the future, this approach may be a potentially powerful tool to discovery active components of traditional Chinese medicines and elucidate their mechanisms.

The efficacy and safety of concentrated herbal extract granules, YH1, as an add-on medication in poorly controlled type 2 diabetes: A randomized, double-blind, placebo-controlled pilot trial

Background

In Asian countries, many patients with type 2 diabetes fail to achieve controlled glycated hemoglobin (HbA_1c) levels while taking several classes of oral hypoglycemic agents (OHAs). Traditional Chinese medicine could be an alternative therapeutic option for poorly controlled type 2 diabetes. YH1 is a concentrated Chinese herbal extract formula that combines Rhizoma Coptidis and Shen-Ling-Bai-Zhu-San. This randomized, double-blind, placebo-controlled pilot study evaluated YH1 as an add-on medication for poorly controlled type 2 diabetes.

Methods

Forty-six patients with poorly controlled type 2 diabetes were randomly assigned 1:1 to the YH1 or placebo group. Before the trial, all subjects had received three or more classes of OHAs with HbA_1c > 7.0% (53 mmol/mol) and a body mass index ≥ 23 kg/m². During the 12-week trial, participants continued to take OHAs without any dose or medication changes. The primary endpoint was the percentage change in HbA_1c level. Per-protocol analysis was applied to the final evaluation.

Results

At week 12, there was an 11.1% reduction in HbA_1c from baseline and a 68.9% increase in homeostatic model assessment (HOMA) of β cell function in the YH1 group, which also exhibited significant reductions in two-hour postprandial glucose (-26.2%), triglycerides (-29.5%), total cholesterol (-21.6%), low-density lipoprotein cholesterol (-17.4%), body weight (-0.5%), and waist circumference (-1.1%). The changes in fasting plasma glucose, HOMA insulin resistance and symptom scores were not significantly different between the YH1 and placebo groups. No serious adverse events occurred during this clinical trial.

Conclusions

This pilot study indicates that YH1 together with OHAs can improve hypoglycemic action and β-cell function in overweight/obese patients with poorly controlled type 2 diabetes. YH1 is a safe add-on medication for OHAs and has beneficial effects on weight control and lipid metabolism. A larger study population with longer treatment and follow-up periods is required for further verification.

Allantoin attenuates deficits of behavioural and motor nerve conduction in an animal model of cisplatin-induced neurotoxicity in rats

BACKGROUND

The aim of the present study was to evaluate the neuroprotective effect of allantoin in cisplatin-induced toxicity in rats.

METHODS

Adult male Wistar rats weighing 160-200 g were used. Neuropathy was induced by injecting cisplatin (2 mg/kg, ip, twice a week for 6 weeks) and the rats were concurrently treated with allantoin (200 and 400 mg/kg, po) for 8 weeks. At the end of the study, body weight and hemogram were measured. Behavioural tests were performed, including tests for cold and hot hyperalgesia, motor co-ordination, locomotor activity, mechano-tactile allodynia and mechanical hyperalgesia. The rats were then sacrificed and sciatic nerve conduction velocity was determined. The antioxidant enzyme and nitric oxide levels in sciatic nerve homogenates were measured.

RESULTS

In this study, allantoin restored the motor nerve conduction velocity deficits induced by cisplatin, and the allantoin-treated rats showed improvement in cold and thermal hyperalgesia, mechano-tactile allodynia, and mechanical hyperalgesia. Allantoin treatment also improved the rats' hematological status, increasing haemoglobin, platelet and RBC counts compared to the cisplatin-treated group. Allantoin treatment also mitigated the functional abnormalities seen in the cisplatin neuropathy group, protecting neurons from the neurotoxic effects of cisplatin.

CONCLUSION

Allantoin shows promise for use as an adjuvant drug in cancer treatment to protect against cisplatin-induced neuropathy.

Metabolites related to purine catabolism and risk of type 2 diabetes incidence; modifying effects of the TCF7L2-rs7903146 polymorphism

Studies examining associations between purine metabolites and type 2 diabetes (T2D) are limited. We prospectively examined associations between plasma levels of purine metabolites with T2D risk and the modifying effects of transcription factor-7-like-2 (TCF7L2) rs7903146 polymorphism on these associations. This is a case-cohort design study within the PREDIMED study, with 251 incident T2D cases and a random sample of 694 participants (641 non-cases and 53 overlapping cases) without T2D at baseline (median follow-up: 3.8 years). Metabolites were semi-quantitatively profiled with LC-MS/MS. Cox regression analysis revealed that high plasma allantoin levels, including allantoin-to-uric acid ratio and high xanthine-to-hypoxanthine ratio were inversely and positively associated with T2D risk, respectively, independently of classical risk factors. Elevated plasma xanthine and inosine levels were associated with a higher T2D risk in homozygous carriers of the TCF7L2-rs7903146 T-allele. The potential mechanisms linking the aforementioned purine metabolites and T2D risk must be also further investigated.

An oral toxicity test in rats and a genotoxicity study of extracts from the stems of Opuntia ficus-indica var. saboten

BACKGROUND

Opuntia ficus-indica var. saboten (OFIS) is used widely in Korea to treat constipation due to its diuretic effects and its enhancement of bowel function and appetite. However, its safety has not yet been established. The aim of this study was to evaluate the repeated oral toxicity and genotoxicity of OFIS extract (OE).

METHODS

White female and male Sprague Dawley rats (n = 6) were divided into 4 groups, and OE was administered to them orally (0, 500, 1000, and 2000 mg/kg/day, respectively) for one week. The Ames test, the chromosomal aberration assay, and the mammalian micronucleus test were performed to determine the OE genotoxicity. The Ames test was conducted using Salmonella typhimurium (S. typhimurium) strains TA100, TA1535, TA98, and TA153 and Escherichia coli (E. coli) WP2 urvA, and Chinese hamster lung (CHL) cells were used for the chromosomal aberration assay. The mammalian micronucleus test was performed using mouse bone marrow cells.

RESULTS

This study revealed that OE administration did not alter the normal rat behavior, body weight gain, and food and water consumption with respect to the normal controls. In addition, there were no toxic effects observed during the ophthalmological test. The biochemical hematological and serum values as well as urinalysis parameters and organ weights were all similar to those of the normal control group. In addition, no mutagenicity effects from the OE were found in S. typhimurium or E. coli with or without S9 activation according to the Ames test. The OE did not significantly alter the number of structural aberrations in the CHL cells in the presence or absence of S9 activation. The oral administration of OE also caused no significant increase in the number of micronucleated polychromatic erythrocytes or in the mean ratio of polychromatic to total erythrocytes.

CONCLUSIONS

In conclusion, OE could be considered as a reliable and safe herbal medicine or functional food since no toxicity was found under the conditions of this study.

Protective Effects of Dioscorea batatas Flesh and Peel Extracts against Ethanol-Induced Gastric Ulcer in Mice

Gastric ulcer is a major digestive disorder and provoked by multifactorial etiologies, including excessive alcohol consumption. In this study, we examined the gastroprotective effect of aqueous and ethanolic extracts of Dioscorea batatas Decne (DBD; commonly called Chinese yam) flesh or peel against acidified ethanol-induced acute gastric damage in mice. Our findings demonstrated that oral supplementation of aqueous or ethanolic extracts of DBD flesh or peel before ulcer induction was significantly effective in macroscopically and histologically alleviating ethanol-induced pathological lesions in gastric mucosa, decreasing the plasma levels of inflammatory mediators, such as nitric oxide and interleukin-6, attenuating the gastric expression of cyclooxygenase-2, and increasing the gastric content of prostaglandin E₂. In particular, pretreatment with the flesh extract prepared in 60% ethanol prominently decreased the expression of biomarkers of oxidative stress, including the plasma levels of 8-hydroxy-2-guanosine and malondialdehyde, and restored heme oxygenase-1 expression and superoxide dismutase activity in the stomach. Overall, these findings suggest that the oral supplementation with DBD extract, especially flesh ethanol extract, prior to excessive alcohol consumption, may exert a protective effect against ethanol-induced gastric mucosal damage in vivo, presumably through the activation of the antioxidant system and suppression of the inflammatory response.

Effects of Rhizome Extract of Dioscorea batatas and Its Active Compound, Allantoin, on the Regulation of Myoblast Differentiation and Mitochondrial Biogenesis in C2C12 Myotubes

With the aging process, a loss of skeletal muscle mass and dysfunction related to metabolic syndrome is observed in older people. Yams are commonly use in functional foods and medications with various effects. The present study was conducted to investigate the effects of rhizome extract of Dioscorea batatas (Dioscoreae Rhizoma, Chinese yam) and its bioactive compound, allantoin, on myoblast differentiation and mitochondrial biogenesis in skeletal muscle cells. Yams were extracted in water and allantoin was analyzed by high performance liquid chromatography (HPLC). The expression of myosin heavy chain (MyHC) and mitochondrial biogenesis-regulating factors, peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α), sirtuin-1 (Sirt-1), nuclear respiratory factor-1 (NRF-1) and transcription factor A, mitochondrial (TFAM), and the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) were determined in C2C12 myotubes by reverse transcriptase (RT)-polymerase chain reaction (RT-PCR) or western blot. The glucose levels and total ATP contents were measured by glucose consumption, glucose uptake and ATP assays, respectively. Treatment with yam extract (1 mg/mL) and allantoin (0.2 and 0.5 mM) significantly increased MyHC expression compared with non-treated myotubes. Yam extract and allantoin significantly increased the expression of PGC-1α, Sirt-1, NRF-1 and TFAM, as well as the phosphorylation of AMPK and ACC in C2C12 myotubes. Furthermore, yam extract and allantoin significantly increased glucose uptake levels and ATP contents. Finally, HPLC analysis revealed that the yam water extract contained 1.53% of allantoin. Yam extract and allantoin stimulated myoblast differentiation into myotubes and increased energy production through the upregulation of mitochondrial biogenesis regulators. These findings indicate that yam extract and allantoin can help to prevent skeletal muscle dysfunction through the stimulation of the energy metabolism.

Radiation-induced overexpression of transthyretin inhibits retinol-mediated hippocampal neurogenesis

Cranial irradiation is the main therapeutic strategy for treating primary and metastatic brain tumors. However, radiation is well-known to induce several unexpected side effects including emotional disorders. Although radiation-induced depression may cause decreased quality of life after radiotherapy, investigations of its molecular mechanism and therapeutic strategies are still insufficient. In this study, we found that behavioral symptoms of depression on mice models with the decrease of BrdU/NeuN- and Dcx-positive populations and MAP-2 expression in hippocampus were induced by cranial irradiation, and transthyretin (TTR) was highly expressed in hippocampus after irradiation. It was shown that overexpression of TTR resulted in the inhibition of retinol-mediated neuritogenesis. PAK1 phosphorylation and MAP-2 expression were significantly reduced by TTR overexpression following irradiation. Moreover, we observed that treatment of allantoin and neferine, the active components of Nelumbo nucifera, interrupted irradiation-induced TTR overexpression, consequently leading to the increase of PAK1 phosphorylation, neurite extension, BrdU/NeuN- and Dcx-positive populations, and MAP-2 expression. Behavioral symptoms of depression following cranial irradiation were also relieved by treatment of allantoin and neferine. These findings demonstrate that TTR plays a critical role in neurogenesis after irradiation, and allantoin and neferine could be potential drug candidates for recovering the effects of radiation on neurogenesis and depression.

Renoprotective Effect of a Chinese Herbal Formula, Qidan Dihuang Decoction, on Streptozotocin-Induced Diabetes in Rat

Qidan Dihuang decoction (QDD) is the latest development of Chinese medicine compound and mainly provides renal protection. The study presented was designed to evaluate the renoprotective effects of QDD on streptozotocin-induced diabetes and to explore the possible mechanisms of this action. We established a diabetes rat model. The condition of the rats was observed. The biochemistry indexes for diabetic rats were examined. Renal tissues were stained with HE, PAS, and Masson and we performed immunohistochemical staining for α-SMA and TGF-β. The proteins expressions of α-SMA, TGF-β, renin, and AT1 were detected by western blot. After treatment for 8 weeks, serum creatinine and 24 h proteinuria were significantly reduced in the rats which received losartan and Qidan Dihuang decoction while blood glucose, urine volume, blood urea nitrogen, and KW/BW did not improve. The pathology of renal tissue of rats treated with losartan and Qidan Dihuang decoction was inhibited. In addition, western blot showed that the expression of α-SMA, TGF-β, renin, and AT1 proteins was significantly decreased after receiving Qidan Dihuang decoction and losartan. Taken together, the results indicate that Qidan Dihuang decoction can improve the renal function and inhibit renal fibrosis of DN rat via modulating RAS system.

Anti-Diabetic Effect of Cotreatment with Quercetin and Resveratrol in Streptozotocin-Induced Diabetic Rats

Quercetin and resveratrol are known to have beneficial effects on the diabetes and diabetic complication, however, the effects of combined treatment of these compounds on diabetes are not fully revealed. Therefore, the present study was designed to investigate the combined antidiabetic action of quercetin (QE) and resveratrol (RS) in streptozotocin (STZ)-induced diabetic rats. To test the effects of co-treated with these compounds on diabetes, serum glucose, insulin, lipid profiles, oxidative stress biomarkers, and ions were determined. Additionally, the activities of hepatic glucose metabolic enzymes and histological analyses of pancreatic tissues were evaluated. 50 male Sprague-Dawley rats were divided into five groups; normal control, 50 mg/kg STZ-induced diabetic, and three (30 mg/kg QE, 10 mg/kg RS, and combined) compound-treated diabetic groups. The elevated serum blood glucose levels, insulin levels, and dyslipidemia in diabetic rats were significantly improved by QE, RS, and combined treatments. Oxidative stress and tissue injury biomarkers were dramatically inhibited by these compounds. They also shown to improve the hematological parameters which were shown to the hyperlactatemia and ketoacidosis as main causes of diabetic complications. The compounds treatment maintained the activities of hepatic glucose metabolic enzymes and structure of pancreatic β-cells from the diabetes, and it is noteworthy that cotreatment with QE and RS showed the most preventive effect on the diabetic rats. Therefore, our study suggests that cotreatment with QE and RS has beneficial effects against diabetes. We further suggest that cotreatment with QE and RS has the potential for use as an alternative therapeutic strategy for diabetes.

Towards natural mimetics of metformin and rapamycin

Aging is now at the forefront of major challenges faced globally, creating an immediate need for safe, widescale interventions to reduce the burden of chronic disease and extend human healthspan. Metformin and rapamycin are two FDA-approved mTOR inhibitors proposed for this purpose, exhibiting significant anti-cancer and anti-aging properties beyond their current clinical applications. However, each faces issues with approval for off-label, prophylactic use due to adverse effects. Here, we initiate an effort to identify nutraceuticals-safer, naturally-occurring compounds-that mimic the anti-aging effects of metformin and rapamycin without adverse effects. We applied several bioinformatic approaches and deep learning methods to the Library of Integrated Network-based Cellular Signatures (LINCS) dataset to map the gene- and pathway-level signatures of metformin and rapamycin and screen for matches among over 800 natural compounds. We then predicted the safety of each compound with an ensemble of deep neural network classifiers. The analysis revealed many novel candidate metformin and rapamycin mimetics, including allantoin and ginsenoside (metformin), epigallocatechin gallate and isoliquiritigenin (rapamycin), and withaferin A (both). Four relatively unexplored compounds also scored well with rapamycin. This work revealed promising candidates for future experimental validation while demonstrating the applications of powerful screening methods for this and similar endeavors.