Effect of Cucumis sativus on Dysfunctional 3T3-L1 Adipocytes

Anti-adipogenic effect of Malva parviflora on 3T3-L1 adipocytes

Malva parviflora has shown anti-inflammatory, antihypertensive, antihyperlipidemic, and hypoglycemic effects. This study is aimed to evaluate the anti-adipogenic effect of M. parviflora on 3T3-L1 adipocytes. Fibroblast differentiation was induced either in the absence or presence of M. parviflora fractions (F3, F4, F7, F12, F13, F17, F18 and F19) for 4 days; F17 and 18 were the most effective fractions in reducing intracellular lipid accumulation (by 25.6% and 23.1%, respectively). EC50 of F17 and F18 (14 μg/mL and 17 μg/mL, respectively) were used to evaluate their anti adipogenic effect. After 10 days of inducing differentiation in the absence or presence of the extracts at the EC50 of F17 and F18, lipid accumulation, the concentration of interleukin 6 (IL-6) were measured in the culture medium; the presence of PPAR-γ, AKT, and p-AKT was also determined. In differentiated adipocytes (C2), F17 maintained intracellular lipid concentration at levels comparable to metformin, while decreasing PPAR-γ and increasing p-AKT presence; it also prevented IL-6 expression. F17 consists of alanine, valine, phenylalanine, and proline. On the other hand, F18 reduced intracellular lipid concentrations, prevented the increase of PPAR-γ and p-AKT, and maintained IL-6 expression at similar levels as metformin. F18 is mainly constituted by alanine, valine, proline, and sucrose. In conclusion, M. parviflora fractions (F17 and F18) control the process of adipogenesis, lipogenesis, and cellular dysfunction.

Hydroalcoholic extract from Sechium edule (Jacq.) S.w. root reverses oleic acid-induced steatosis and insulin resistance in vitro

Steatosis is characterized by fat accumulation and insulin resistance (IR) in hepatocytes, which triggers a pro-oxidant, pro-inflammatory environment that may eventually lead to cirrhosis or liver carcinoma. This work was aimed to assess the effect of Sechium edule root hydroalcoholic extract (rSe-HA) (rich in cinnamic and coumaric acid, among other phenolic compounds) on triglyceride esterification, lipid degradation, AMPK expression, and the phosphorylation of insulin receptor in a Ser312 residue, as well as on the redox status, malondialdehyde (MDA) production, and the production of proinflammatory cytokines in an in vitro model of steatosis induced by oleic acid, to help develop a phytomedicine that could reverse this pathology. rSe-HA reduced triglyceride levels in hepatocyte lysates, increased lipolysis by activating AMPK at Thr172, and improved the redox status, as evidenced by the concentration of glycerol and formazan, respectively. It also prevented insulin resistance (IR), as measured by glucose consumption and the phosphorylation of the insulin receptor at Ser312. It also prevented TNFα and IL6 production and decreased the levels of MDA and nitric oxide (ON). Our results indicate that rSe-HA reversed steatosis and controlled the proinflammatory and prooxidant environment in oleic acid-induced dysfunctional HepG2 hepatocytes, supporting its potential use to control this disorder.

Vindoline Exhibits Anti-Diabetic Potential in Insulin-Resistant 3T3-L1 Adipocytes and L6 Skeletal Myoblasts

Type 2 diabetes mellitus (T2DM) emerged as a major health care concern in modern society, primarily due to lifestyle changes and dietary habits. Obesity-induced insulin resistance is considered as the major pathogenic factor in T2DM. In this study, we investigated the effect of vindoline, an indole alkaloid of Catharanthus roseus on insulin resistance (IR), oxidative stress and inflammatory responses in dexamethasone (IR inducer)-induced dysfunctional 3T3-L1 adipocytes and high-glucose-induced insulin-resistant L6-myoblast cells. Results showed that dexamethasone-induced dysfunctional 3T3-L1 adipocytes treated with different concentrations of vindoline significantly enhanced basal glucose consumption, accompanied by increased expression of GLUT-4, IRS-1 and adiponectin. Similarly, vindoline-treated insulin-resistant L6 myoblasts exhibited significantly enhanced glycogen content accompanied with upregulation of IRS-1 and GLUT-4. Thus, in vitro studies of vindoline in insulin resistant skeleton muscle and dysfunctional adipocytes confirmed that vindoline treatment significantly mitigated insulin resistance in myotubes and improved functional status of adipocytes. These results demonstrated that vindoline has the potential to be used as a therapeutic agent to ameliorate obesity-induced T2DM-associated insulin resistance profile in adipocytes and skeletal muscles.

Synergism and Subadditivity of Verbascoside-Lignans and -Iridoids Binary Mixtures Isolated from Castilleja tenuiflora Benth. on NF-κB/AP-1 Inhibition Activity

Pharmacodynamic interactions between plant isolated compounds are important to understand the mode of action of an herbal extract to formulate or create better standardized extracts, phytomedicines, or phytopharmaceuticals. In this work, we propose binary mixtures using a leader compound to found pharmacodynamic interactions in inhibition of the NF-κB/AP-1 pathway using RAW-Blue™ cells. Eight compounds were isolated from Castilleja tenuiflora, four were new furofuran-type lignans for the species magnolin, eudesmin, sesamin, and kobusin. Magnolin (60.97%) was the most effective lignan inhibiting the NF-κB/AP-1 pathway, followed by eudesmin (56.82%), tenuifloroside (52.91%), sesamin (52.63%), and kobusin (45.45%). Verbascoside, a major compound contained in wild C. tenuiflora showed an inhibitory effect on NF-κB/AP-1. This polyphenol was chosen as a leader compound for binary mixtures. Verbacoside-aucubin and verbascoside-kobusin produced synergism, while verbascoside-tenuifloroside had subadditivity in all concentrations. Verbascoside-kobusin is a promising mixture to use on NF-κB/AP-1 related diseases and anti-inflammatory C. tenuiflora-based phytomedicines.