Safety and efficacy of Melissa officinalis (lemon balm) on ApoA-I, Apo B, lipid ratio and ICAM-1 in type 2 diabetes patients: A randomized, double-blinded clinical trial

Effects of Melissa officinalis (lemon balm) consumption on serum lipid profile: a meta-analysis of randomized controlled trials

BACKGROUND

According to traditional medicine, Melissa officinalis L., (lemon balm) has been known to remove harmful substances from the blood and is considered a cardiac tonic. Therefore, its use as a cardiovascular remedy may explain the lipid-lowering effects of lemon balm. Dyslipidemia can be considered as a significant preventable risk factor for atherosclerosis, coronary heart disease and type 2 diabetes. The present study is the first meta-analysis to investigate the effects of M. officinalis administration on serum levels of high-density lipoprotein cholesterol (HDL), low-density lipoprotein cholesterol (LDL), triglyceride (TG) and total cholesterol (TC).

METHODS

From inception to October 2023, a thorough search through literature was conducted using PubMed, Scopus, and Web of Science. The inclusion criteria of this study were randomized controlled trials, with or without blinding which provided adequate data for each group at the beginning and end of the follow-up period. Meta-analysis was performed on randomized controlled trials using Comprehensive Meta-Analysis (CMA) V4 software. Risk of bias in the selected studies was examined according to the revised Cochrane risk-of-bias tool for randomized trials. Begg's funnel plot symmetry status, Begg's rank correlation, and Egger's weighted regression tests were employed to evaluate potential publication bias.

RESULTS

The meta-analysis comprised of 5 randomized controlled trials with a total of 302 patients. The findings of the meta-analysis indicated that the consumption of lemon balm had a significant decrease in TG (SMD (95% CI): -0.396(-0.620, -0.173), p-value = 0.001), TC (SMD (95% CI): -0.416 (-0.641, -0.192), p-value < 0.001) and LDL (SMD (95% CI): -0.23(-0.45, -0.008), p < 0.05) levels compared to the placebo group. While it had no statistically significant effect on HDL level (SMD (95% CI): 0.336(-0.091, 0.767), p-value = 0.123). No significant and detectable publication bias was found in the meta-analysis. Additionally, all included clinical studies demonstrated a low risk of bias for missing outcome data and selection of the reported results. The robustness of the results was demonstrated by a sensitivity analysis using the one-study remove method.

CONCLUSIONS

The findings of this meta-analysis provide evidence that lemon balm may be administered as a safe and beneficial herbal medicine for reducing TC, TG and LDL levels. According to the pooled results of 5 studies with a total of 302 patients, lemon balm intake had no significant effect on HDL level. This study reinforces the notion that lemon balm may have a substantial impact on serum lipid profile as a potential remedy in cases of dyslipidemia. The main concern of our research is the limited number of eligible studies and the relatively small population size of each individual study. The patients of these studies had different types of diseases and metabolic syndromes. However, the meta-analysis was sufficiently powered to detect the considerable effects of lemon balm in the combined population regardless of type of diseases.

Plasma Concentrations of Rosmarinic Acid in Patients on Antiretroviral Therapy: In Silico Exploration Based on Clinical Data

Rosmarinic acid (RA) is a phenolic compound with antiviral properties, often encountered in dietary supplements and herbal drugs. Data on the pharmacokinetics of RA are lacking in cases of the chronic use of supplements containing this compound, and only limited data on the metabolism and distribution of RA are available. The aim of the study was to investigate the plasma levels of RA after 12 weeks of use and determine potential interactions of RA and selected antiretroviral drugs. Patients infected with human immunodeficiency virus took a supplement containing RA for 12 weeks, after which the RA concentrations in the plasma samples were analyzed. A detailed in silico analysis was conducted in order to elucidate the potential interactions between RA and the drugs efavirenz, darunavir and raltegravir. It was found that RA can be detected in patients' plasma samples, mainly in the form of sulphoglucuronide. The potential interactions are suggested on the level of liver metabolizing enzymes and efflux P-glycoprotein, with RA competing with antiretroviral drugs as a substrate in metabolism and distribution systems. The present study suggests that the simultaneous use of RA and antiretroviral therapy (containing efavirenz, darunavir or raltegravir) may affect the plasma levels of RA after prolonged supplementation.

Overview of Natural Supplements for the Management of Diabetes and Obesity

Bioactive compounds found in various natural sources, such as fruits, vegetables, and herbs, have been studied for their potential benefits in managing obesity and diabetes. These compounds include polyphenols, flavonoids, other antioxidants, fiber, and certain fatty acids. Studies have found that these compounds may improve insulin sensitivity, regulate blood sugar levels, and promote weight loss. However, the effects of these compounds can vary depending on the type and amount consumed, as well as individual factors, such as genetics and lifestyle. Nutraceutical substances have multifaceted therapeutic advantages, and they have been reported to have disease-prevention and health-promoting properties. Several clinically used nutraceuticals have been shown to target the pathogenesis of diabetes mellitus, obesity, and metabolic syndrome and their complications and modulate various clinical outcomes favorably. This review aims to highlight and comment on some of the most prominent natural components used as antidiabetics and in managing obesity.

Pathophysiology of diabetic hepatopathy and molecular mechanisms underlying the hepatoprotective effects of phytochemicals

Patients with diabetes are at risk for liver disorders including glycogen hepatopathy, non-alcoholic fatty liver disease, cirrhosis, and hepatic fibrosis. The pathophysiological mechanisms behind diabetic hepatopathy are complex, some of them include fatty acid accumulation, increased reactive oxygen species, increased advanced glycation end-products, hyperactivity of polyol pathways, increased apoptosis and necrosis, and promotion of fibrosis. A growing number of studies have shown that herbal extracts and their active phytochemicals have antihyperglycemic properties and beneficial effects on diabetic complications. The current review, for the first time, focused on herbal agents that showed beneficial effects on diabetic hepatopathy. For example, animal studies have shown that Moringa oleifera and Morus alba improve liver function in both type-1 and type-2 diabetes. Also, evidence from clinical trials suggests that Boswellia serrata, Juglans regia, Melissa officinalis, Portulaca oleracea, Silybum marianum, Talapotaka Churna, and Urtica dioica reduce serum liver enzymes in diabetic patients. The main active ingredient of these plants to protect the liver seems to be phenolic compounds such as niazirin, chlorogenic acid, resveratrol, etc. Mechanisms responsible for the hepatoprotective activity of herbal agents include improving glucose metabolism, restoring adipokines levels, antioxidant defense, and anti-inflammatory activity. Several signaling pathways are involved in hepatoprotective effects of herbal agents in diabetes, such as phosphoinositide 3-kinase, adenosine monophosphate-activated protein kinase, mitogen-activated protein kinase, and c-Jun NH2-terminal kinase.

The effects of melissa officinalis on depression and anxiety in type 2 diabetes patients with depression: a randomized double-blinded placebo-controlled clinical trial

BACKGROUND

Depression is more common in diabetic patients, with a 1.5-fold increased risk of death.Melissa officinalis (M. officinalis) have anti-diabetic and anti-depression activities. The study aimed to determine the efficacy of M. officinalis extract on depression, anxiety, and sleep quality in patients with type 2 diabetes with depressive symptoms.

METHODS

In this double-blind clinical trial, 60 volunteer patients (age range 20-65 years) with type 2 diabetes mellitus with symptoms of depression were randomized into the intervention (received 700 mg/day hydroalcoholic extract; n = 30) or control group (received 700 mg/day toasted flour; n = 30). Dietary intake, physical activity, anthropometric indices, FBS (Fasting blood sugar), hs-CRP(High-sensitivity C-reactiveprotein), depression, anxiety, and sleep quality were determined at the beginning and end of the study. Depression and anxiety were assessed by Beck Depression Inventory-II (BDI-II) and Beck Anxiety Inventory (BAI), respectively; sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI).

RESULTS

Sixty participants received M. officinalis extract or placebo, of which 44 patients completed the 12-week double-blind clinical trial. After 12-week the mean change of depression and anxiety scores were statistically significant between the two groups (p < 0.001 and p = 0.04, respectively), but no significant differences were observed in FBS, hs-CRP, anthropometric indices, sleep quality, and blood pressure.In the intervention group, there was a significant decrease in depression and anxiety severity(p < 0.001 and p = 0.01, respectively) at the end of the study compared to the baseline.

TRIAL REGISTRATION

All protocols in this study were followed in accordance with the Helsinki Declaration (1989 revision). Ethical approval for this study was obtained from the Iran University of Medical Sciences Ethics committee (IR.IUMS.FMD.REC 1396.9413468004; research.iums.ac.ir). The study was registered at the Iranian Registry of Clinical Trials (IRCT201709239472N16); Registration date: 09/10/2017.

The effects of melissa officinalis on depression and anxiety in type 2 diabetes patients with depression: a randomized double-blinded placebo-controlled clinical trial

BACKGROUND

Depression is more common in diabetic patients, with a 1.5-fold increased risk of death.Melissa officinalis (M. officinalis) have anti-diabetic and anti-depression activities. The study aimed to determine the efficacy of M. officinalis extract on depression, anxiety, and sleep quality in patients with type 2 diabetes with depressive symptoms.

METHODS

In this double-blind clinical trial, 60 volunteer patients (age range 20-65 years) with type 2 diabetes mellitus with symptoms of depression were randomized into the intervention (received 700 mg/day hydroalcoholic extract; n = 30) or control group (received 700 mg/day toasted flour; n = 30). Dietary intake, physical activity, anthropometric indices, FBS (Fasting blood sugar), hs-CRP(High-sensitivity C-reactiveprotein), depression, anxiety, and sleep quality were determined at the beginning and end of the study. Depression and anxiety were assessed by Beck Depression Inventory-II (BDI-II) and Beck Anxiety Inventory (BAI), respectively; sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI).

RESULTS

Sixty participants received M. officinalis extract or placebo, of which 44 patients completed the 12-week double-blind clinical trial. After 12-week the mean change of depression and anxiety scores were statistically significant between the two groups (p < 0.001 and p = 0.04, respectively), but no significant differences were observed in FBS, hs-CRP, anthropometric indices, sleep quality, and blood pressure.In the intervention group, there was a significant decrease in depression and anxiety severity(p < 0.001 and p = 0.01, respectively) at the end of the study compared to the baseline.

TRIAL REGISTRATION

All protocols in this study were followed in accordance with the Helsinki Declaration (1989 revision). Ethical approval for this study was obtained from the Iran University of Medical Sciences Ethics committee (IR.IUMS.FMD.REC 1396.9413468004; research.iums.ac.ir). The study was registered at the Iranian Registry of Clinical Trials (IRCT201709239472N16); Registration date: 09/10/2017.

Plant Essential Oils as Healthy Functional Ingredients of Nutraceuticals and Diet Supplements: A Review

Essential oils (EOs) are mixtures of volatile molecules endowed with health-promoting biological activities that go beyond their role as aromas and natural preservatives and can be exploited to develop functional foods and diet supplements. Their composition is briefly addressed along with regulatory aspects. The potential health benefit of human diet supplementation with EOs is outlined through a review of the recent literature on available clinical trials and preclinical research concerning EOs activity towards: (1) irritable bowel syndrome; (2) inflammatory bowel disease; (3) regulation of microbiota; (4) gastroprotection; (5) hepatoprotection; (6) protection of the urinary tract and diuresis; (7) management of metabolic disorders including hyperglycemia and hyperlipidemia; (8) anti-inflammatory and pain control; (9) immunomodulation and protection from influenza; and (10) neuroprotection and modulation of mood and cognitive performance. The emerging potential in such activities of selected EOs is given focus, particularly green and black cumin, bergamot, orange, myrtle, peppermint, sage, eucalyptus, lavender, thyme, lemon balm, ginger, and garlic.

Anti-Diabesity Middle Eastern Medicinal Plants and Their Action Mechanisms

Over the last four decades, the escalation in diabetes and obesity rates has become epidemic all over the world. Diabesity describes the strong link between T2D and obesity. It correlates deeper with the elevated risks of developing cardiovascular disease hypertension, stroke, and several malignancies. Therapeutic usage of medicinal plants and natural products in the treatment of diabetes and obesity has long been known to physicians of Greco-Arab and Islamic medicine. Improved versions of their abundant medicinal plant-based formulations are at present some of the most popular herbal treatments used. Preclinical and clinical data about medicinal plants along with their bioactive constituents are now available, justifying the traditionally known therapeutic uses of products derived from them for the prevention and cure of obesity-related T2D and other health problems. The aim of this review is to systematize published scientific data dealing with the efficiency of active ingredients or extracts from Middle Eastern medicinal plants and diet in the management of diabesity and its complications. Google Scholar, MEDLINE, and PubMed were searched for publications describing the medicinal plants and diet used in the management of T2D, obesity, and their complications. The used keywords were “medicinal plants” or “herbals” in combination with “obesity,” “diabetes,” “diabetes,” or nephropathy. More than 130 medicinal plants were identified to target diabesity and its complications. The antidiabetic and anti-obesity effects and action mechanisms of these plants are discussed here. These include the regulation of appetite, thermogenesis, lipid absorption, and lipolysis; pancreatic lipase activity and adipogenesis; glucose absorption in the intestine, insulin secretion, glucose transporters, gluconeogenesis, and epigenetic mechanisms.

Bioactive Foods and Medicinal Plants for Cardiovascular Complications of Type II Diabetes: Current Clinical Evidence and Future Perspectives

Cardiovascular diseases (CVDs) are the main cause of mortality in type 2 diabetes mellitus (T2DM); however, not all patients are fully satisfied with the current available treatments. Medicinal plants have been globally investigated regarding their effect in CVD, yet the field is far from getting exhausted. The current paper aims to provide an evidence-based review on the clinically evaluated medicinal plants and their main therapeutic targets for the management of CVD in T2DM. Electronic databases including PubMed, Cochrane, Embase, Scopus, and Web of Science were searched from 2000 until November 2019, and related clinical studies were included. Lipid metabolism, glycemic status, systemic inflammation, blood pressure, endothelial function, oxidative stress, and anthropometric parameters are the key points regulated by medicinal plants in T2DM. Anti-inflammatory and antioxidant properties are the two most important mechanisms since inflammation and oxidative stress are the first steps triggering a domino of molecular pathological pathways leading to T2DM and, subsequently, CVD. Polyphenols with potent antioxidant and anti-inflammatory effects, essential oil-derived compounds with vasorelaxant properties, and fibers with demonstrated effects on obesity are the main categories of phytochemicals beneficial for CVD of T2DM. Some medicinal plants such as garlic (Allium sativum) and milk thistle (Silybum marianum) have strong evidences regarding their beneficial effects; however, others have low level of evidence which reveals the need for further clinical studies with larger sample sizes and longer follow-up periods to confirm the safety and efficacy of medicinal plants for the management of CVD in T2DM.

Melissa officinalis L. as a Nutritional Strategy for Cardioprotection

This review aimed to provide a summary on the traditional uses, phytochemistry, and pharmacological activities in the cardiovascular system and cardiotoxicity of Melissa officinalis (MO), with the special emphasis on the protective mechanisms in different cardiovascular pathologies. MO is a perennial aromatic herb commonly known as lemon balm, honey balm, or bee balm, which belongs to Lamiaceae family. Active components are mainly located in the leaves or essential oil and include volatile compounds, terpenoid (monoterpenes, sesquiterpenes, triterpenes), and polyphenolic compounds [rosmarinic acid (RA), caffeic acid, protocatechuic acid, quercitrin, rhamnocitrin, luteolin]. For centuries, MO has been traditionally used as a remedy for memory, cognition, anxiety, depression, and heart palpitations. Up until now, several beneficial cardiovascular effects of MO, in the form of extracts (aqueous, alcoholic, and hydroalcoholic), essential oil, and isolated compounds, have been confirmed in preclinical animal studies, such as antiarrhythmogenic, negative chronotropic and dromotropic, hypotensive, vasorelaxant, and infarct size-reducing effects. Nonetheless, MO effects on heart palpitations are the only ones confirmed in human subjects. The main mechanisms proposed for the cardiovascular effects of this plant are antioxidant free radical-scavenging properties of MO polyphenols, amelioration of oxidative stress, anti-inflammatory effects, activation of M2 and antagonism of β1 receptors in the heart, blockage of voltage-dependent Ca²⁺ channels, stimulation of endothelial nitric oxide synthesis, prevention of fibrotic changes, etc. Additionally, the main active ingredient of MO-RA, per se, has shown substantial cardiovascular effects. Because of the vastness of encouraging data from animal studies, this plant, as well as the main ingredient RA, should be considered and investigated further as a tool for cardioprotection and adjuvant therapy in patients suffering from cardiovascular diseases.

Rosmarinic Acid-Human Pharmacokinetics and Health Benefits

Rosmarinic acid is a phenolic compound commonly found in the Lamiaceae (Labiateae) plant species. It is considered responsible for a wide spectrum of biological and pharmacological activities of plants containing this compound. The aim of the current review is to present the fate of rosmarinic acid inside the human body, explained through pharmacokinetic steps and to briefly present the health benefits of RA. Pharmacokinetics was at first studied in animal models, but several studies were conducted in humans as well. This compound can be applied topically, pulmonary, intranasally, and via intravenous infusion. However, peroral application is the main route of entry into the human body. Presumably, it is mainly metabolized by the gut microflora, providing simple, more easily absorbed phenolic units. Inside the body, the rosmarinic acid molecule undergoes structural changes, as well as conjugation reactions. Renal excretion represents the main path of elimination. Previously conducted studies reported no serious adverse effects of herbal remedies containing RA, as well as their positive effects on human health. In addition to in vitro studies, clinical investigations suggested its benefits in dermatological, allergic, and osteoarthritic disorders, as well as for improving cognitive performance and in metabolic syndrome treatment. Future studies should investigate the kinetics during long-term application in patients who would have potential benefits from RA usage. Pharmaceutical formulations designed to prevent the fast metabolism of RA and allow its penetration into other compartments of the human body are also interesting topics for future research.

The Safety and Efficacy of Botanicals with Nootropic Effects

Recent estimates for the global brain health supplement category, i.e. nootropic market size, will grow to nearly $5.8 billion by 2023. Overall, nearly one-quarter (23%) of adults currently take a supplement to maintain or improve brain health or delay and reverse dementia. Not surprisingly, the use of such supplements increases with age - more than one-third of the oldest generation (ages 74 and older) takes a supplement for brain health. This widespread use is being driven by a strong desire both in the younger and older generations to enhance cognitive performance and achieve healthy aging. The most prevalent botanicals currently dominating the nootropic marketplace include Gingko biloba, American ginseng, and Bacopa monnieri. However, other botanicals that affect stress, focus, attention, and sleep have also been procured by dietary supplement companies developing products for improving both, short and long-term brain health. This review focuses on efficacy data for neuroactive botanicals targeted at improving cognitive function, stress reduction, memory, mood, attention, concentration, focus, and alertness, including Bacopa monnieri, Ginkgo biloba, Holy basil, American ginseng, Gotu kola, Lemon balm, Common and Spanish sages and spearmint. Botanicals are discussed in terms of available clinical efficacy data and current safety profiles. Data gaps are highlighted for both efficacy and safety to bring attention to unmet needs and future research.

Effects of Melissa officinalis (Lemon Balm) on cardio-metabolic outcomes: A systematic review and meta-analysis

Recent evidence indicates a beneficial effect of Melissa officinalis (MO) intake on several chronic diseases. However, the effects of MO intake have not yet been systematically reviewed. Therefore, we conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the effect of MO intake and focused on several cardiometabolic outcomes. MEDLINE, Scopus, EMBASE, Web of Science and the Cochrane Central Register of Controlled Trials were searched for MO-RCTs evaluating cardiometabolic outcomes. Random-effects meta-analyses estimated the pooled standardized mean differences (SMD) between intervention and control groups. Risk of bias was assessed with the Cochrane Collaboration's tool for assessing the risk of bias in RCTs. Seven RCTs were finally deemed eligible. MO intake was associated with a reduced total cholesterol (TC) (SMD: -0.26; 95% CI: -0.52, -0.01; I² = 13.7%; k = 6) and a reduced systolic blood pressure (SBP) (SMD: -0.56; 95% CI: -0.85, -0.27; I² = 00.0%; k = 3). MO intake was not associated with statistically significant changes in triglycerides, low-density lipoprotein, diastolic blood pressure, high sensitivity c-reactive protein levels, fasting blood sugar, HbA1c, insulin or high-density lipoprotein levels. No serious adverse events were reported. The risk of bias was high in a considerable amount of studies. Our study suggests that MO is a safe supplement with beneficial effects on TC and SBP. However, the findings of our study must be seen in the light of major limitations such as a low number of included studies and a serious risk of bias. High-quality RCTs are needed for firm conclusions concerning the effects of MO on cardiometabolic outcomes.

Lemon balm and dandelion leaf extract synergistically alleviate ethanol-induced hepatotoxicity by enhancing antioxidant and anti-inflammatory activity

We investigated the effect of a 2:1 (w/w) mixture of lemon balm and dandelion extracts (LD) on ethanol (EtOH)-mediated liver injury and explored the underlying mechanisms. Administration of LD synergistically reduced relative liver weight and decreased the levels of serum biomarkers of hepatic injury. Histopathological and biochemical analyses indicated that LD synergistically attenuated hepatic accumulation of triacylglycerides (TGs) and restored the levels of mRNAs related to fatty acid metabolism. In addition, LD significantly reduced EtOH-induced hepatic oxidative stress by attenuating the reduction in levels of nuclear factor E2-related factor 2 (Nrf2) mRNA and enhancing antioxidant activity. Moreover, LD decreased the EtOH-mediated increase in levels of hepatic tumor necrosis factor-α (TNF-α) mRNA. In vitro, LD significantly scavenged free radicals, increased cell viability against tert-butylhydroperoxide (tBHP), and transactivated Nrf2 target genes in HepG2 cells. Furthermore, LD decreased levels of pro-inflammatory mediators in lipopolysaccharide-stimulated Raw264.7 cells. Therefore, LD shows promise for preventing EtOH-mediated liver injury. PRACTICAL APPLICATIONS: There were no approved therapeutic agents for preventing and/or treating alcoholic liver diseases. In this study, a 2:1 (w/w) mixture of lemon balm and dandelion leaf extract (DL) synergistically ameliorated EtOH-induced hepatic injury by inhibiting lipid accumulation, oxidative stress, and inflammation. Our findings will enable the development of a novel food supplement for the prevention or treatment of alcohol-mediated liver injury.

Role of phytochemicals as nutraceuticals for cognitive functions affected in ageing

Cognitive decline can occur with normal ageing and in age-related brain disorders, such as mild cognitive impairment and dementia, including Alzheimer's disease, with limited pharmacological therapies available. Other approaches to reduce cognitive decline are urgently needed, and so, the role of dietary interventions or nutraceuticals has received much attention in this respect. In this review, we examine the evidence for dietary plants and their chemical constituents as nutraceuticals, relevant to both cognitive decline in normal ageing and in dementia. Pharmacological (in vitro and in vivo), clinical and epidemiological evidence is assessed for both frequently consumed plants and their dietary forms, including tea, coffee, cocoa (chocolate), red wine, grapes, citrus and other fruits; in addition to plants used less frequently in certain diets and those that cross the blurred boundaries between foods, nutraceuticals and medicinal plants. For the latter, turmeric, saffron, sage, rosemary and lemon balm are examples of those discussed. LINKED ARTICLES: This article is part of a themed section on The Pharmacology of Nutraceuticals. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v177.6/issuetoc.

A Two-Week Treatment with Plant Extracts Changes Gut Microbiota, Caecum Metabolome, and Markers of Lipid Metabolism in ob/ob Mice

SCOPE

Targeting gut microbiota dysbiosis by prebiotics is effective, though side effects such as abdominal bloating and flatulence may arise following high prebiotic consumption over weeks. The aim is therefore to optimize the current protocol for prebiotic use.

METHODS AND RESULTS

To examine the prebiotic properties of plant extracts, two independent studies are conducted in ob/ob mice, over two weeks. In the first study, Porphyra umbilicalis and Melissa officinalis L. extracts are evaluated; in the second study, a high vs low dose of an Emblica officinalis Gaertn extract is assessed. These plant extracts affect gut microbiota, caecum metabolome, and induce a significant lower plasma triacylglycerols (TG) following treatment with P. umbilicalis and significantly higher plasma free fatty acids (FFA) following treatment with the low-dose of E. officinalis Gaertn. Glucose- and insulin-tolerance are not affected but white adipose tissue and liver gene expression are modified. In the first study, IL-6 hepatic gene expression is significantly (adjusted p = 0.0015) and positively (r = 0.80) correlated with the bacterial order Clostridiales in all mice.

CONCLUSION

The data show that a two-week treatment with plant extracts affects the dysbiotic gut microbiota and changes both caecum metabolome and markers of lipid metabolism in ob/ob mice.

Geniposide Improves Glucose Homeostasis via Regulating FoxO1/PDK4 in Skeletal Muscle

It is well-known that imbalance state of glucose metabolism triggers many metabolic diseases and glucose uptake in skeletal muscle accounts for 90% of body weight. Geniposide is one of the major natural bioactive constituents of gardenia fruit, and the regulation of geniposide on glucose metabolism in skeletal muscle has not yet been investigated. Here, on the basis of microarray analysis, we discovered that geinposide decreased pyruvate dehydrogenase kinase 4 (PDK4) expression in skeletal muscle of mice and subsequently found that geniposide inhibited the expressions of forkhead box O1 (FoxO1), PDK4, and phosphorylated pyruvate dehydrogenase in vitro and in vivo. Moreover, geniposide promoted a switch of slow-to-fast myofiber type and glucose utilization, suggesting that geniposide improved glucose homeostasis. In addition, mechanistic studies revealed that geniposide played above roles by regulating FoxO1/PDK4, which controlled fuel selection via pyruvate dehydrogenase. Meanwhile, effects of geniposide mentioned above could be reversed by FoxO1 overexpression. Together, these results establish that geniposide confers controls on fuel usage and glucose homeostasis through FoxO1/PDK4 in skeletal muscle.