Synthesis of Hoodigogenin A, aglycone of natural appetite suppressant glycosteroids extracted from Hoodia gordonii

Natural products as novel anti-obesity agents: insights into mechanisms of action and potential for therapeutic management

Obesity affects more than 10% of the adult population globally. Despite the introduction of diverse medications aimed at combating fat accumulation and obesity, a significant number of these pharmaceutical interventions are linked to substantial occurrences of severe adverse events, occasionally leading to their withdrawal from the market. Natural products serve as attractive sources for anti-obesity agents as many of them can alter the host metabolic processes and maintain glucose homeostasis via metabolic and thermogenic stimulation, appetite regulation, pancreatic lipase and amylase inhibition, insulin sensitivity enhancing, adipogenesis inhibition and adipocyte apoptosis induction. In this review, we shed light on the biological processes that control energy balance and thermogenesis as well as metabolic pathways in white adipose tissue browning, we also highlight the anti-obesity potential of natural products with their mechanism of action. Based on previous findings, the crucial proteins and molecular pathways involved in adipose tissue browning and lipolysis induction are uncoupling protein-1, PR domain containing 16, and peroxisome proliferator-activated receptor-γ in addition to Sirtuin-1 and AMP-activated protein kinase pathway. Given that some phytochemicals can also lower proinflammatory substances like TNF-α, IL-6, and IL-1 secreted from adipose tissue and change the production of adipokines like leptin and adiponectin, which are important regulators of body weight, natural products represent a treasure trove for anti-obesity agents. In conclusion, conducting comprehensive research on natural products holds the potential to accelerate the development of an improved obesity management strategy characterized by heightened efficacy and reduced incidence of side effects.

Ginger Water Reduces Body Weight Gain and Improves Energy Expenditure in Rats

Obesity is a serious global problem that causes predisposition to numerous serious diseases. The current study aims to investigate the effect of ginger water on body weight and energy expenditure through modulation of mRNA expression of carbohydrate and lipid metabolism. A white colored liquid obtained during freeze-drying of fresh rhizomes of Zingiber officinal was collected and named ginger water. It was used to treat rats, then blood and tissue samples were collected from the liver and white adipose at the end of the experiment. The serum was prepared and used for biochemical assays, while tissue samples were used for RNA isolation and gene expression analysis via Reverse transcription polymerase chain reaction (RT-PCR). Results of High Performance Liquid Chromatography (HPLC) analysis of ginger water revealed the presence of chrysin and galangin at concentrations of 0.24 µg/mL and 0.53 µg/mL, respectively. Average body weight gain decreased significantly in groups that received ginger water. In addition, both total cholesterol and serum triacylglycerol were reduced in the groups that received ginger water. Furthermore, mRNA expression of Sterol regulatory element-binding protein 1 (SREBP-1c) in the liver and leptin in adipose tissues were downregulated, while those of adiponectin, hepatic carnitine palmitoyltransferase1 (CPT-1), acyl-coA oxidase (ACO), Glucose transporter 2 (GLUT-2), and pyruvate kinase (PK) were upregulated in ginger water-treated groups. These results clearly revealed the lowering body weight gain effect of ginger water, which most likely occurs at the transcriptional level of energy metabolizing proteins.

C-12 vs C-3 substituted bile salts: An example of the effects of substituent position and orientation on the self-assembly of steroid surfactant isomers

Biomolecule derivatives are transversally used in nanotechnology. Deciphering their aggregation behavior is a crucial issue for the rational design of functional materials. To this end, it is necessary to build libraries of selectively functionalized analogues and infer general rules. In this work we enrich the highly applicative oriented collection of steroid derivatives, by reporting a rare example of C-12 selectively modified bile salt. While nature often exploits such position to encode functions, it is unusual and not trivial to prepare similar analogues in the laboratory. The introduction of a tert-butyl phenyl residue at C-12 provided a molecule with a self-assembly that remarkably switched from rigid pole-like structures to twisted ribbons at a biologically relevant critical temperature (∼25 °C). The system was characterized by microscopy and spectroscopy techniques and compared with the C-3 functionalized analogue. The twisted ribbons generate samples with a gel texture and a viscoelastic response. The parallel analysis of the two systems suggested that the observed thermoresponsive self-assemblies occur at similar critical temperatures and are probably dictated by the nature of the substituent, but involve aggregates with different structures depending on position and orientation of the substituent. This study highlights the self-assembly properties of two appealing thermoresponsive systems. Moreover, it adds fundamental insights hereto missing in the investigations of the relation between self-assembly and structure of synthetic steroids, which are valuable for the rational design of steroidal amphiphiles.

Antiosteoporotic effect of Hemidesmus indicus Linn. on ovariectomised rats

PHARMACOLOGICAL RELEVANCE

Root of Hemidesmus indicus (L). R. Br., an herbal drug of India is traditionally used to prevent or treat female hormonal disturbance related disorders and assuaging symptoms of menopausal conditions.

AIM OF THE STUDY

Lack of scientific data for potential use in bone loss, the present study was undertaken to investigate the effects of ethanol extract of Hemidesmus indicus root for osteoporosis in ovariectomised rats.

MATERIALS AND METHODS

Thirty wistar female rats were randomly divided into five groups. One group was sham operated and other four groups were undergone dorsal ovariectomy (OVX). After four weeks of post-operative recovery, three OVX groups, viz. Group1, Group2 and Group3 were treated for ninety days with standard raloxifene (RLX) 1mg/kg/day, Hemidesmus indicus root extract (HIRE) 100mg/kg/day and HIRE 200mg/kg/day respectively. Sham and OVX control groups were fed with equal 1% vehicle volume. Serum and urine biochemistry (alkaline phosphatase, tartrate resistant acid phosphatase, triglyceride, total cholesterol, calcium, phosphorous and hydroxyproline), weight of body, uterus and vagina, femur parameters, three point bending of tibia and fourth lumbar vertebra compression were examined. Furthermore, bone architecture and uterine hypertrophy were examined by histopathological studies.

RESULTS

Application of HIRE has increased bone strength and restored bone turnover markers such as alkaline phosphatase, tartrate resistant acid phosphatase and hydroxyproline moreover, improved femur parameters indicated mineralized bones, similar to the results observed with raloxifene treatment. Histopathology studies showed fibrocartilaginous proliferation of trabecular bone and absence of uterine hypertrophy.

CONCLUSION

The results strongly suggest that HIRE prevents bone loss in OVX induced osteoporosis without estrogen like side effects. It might be a potential remedy like raloxifene for postmenopausal or estrogen deficiency caused osteoporosis.

Slimming and Appetite-Suppressing Effects of Caraway Aqueous Extract as a Natural Therapy in Physically Active Women

Following the current 'Globesity' trend, there is an increasing demand for alternative natural therapies for weight management. Numerous phytoconstituents reduce body weight through suppressing appetite and reducing food intake. Caraway (Carum carvi L.) is one of the medicinal plants that is traditionally used for weight loss. In this study, the appetite-suppressing effects of caraway aqueous extract (CAE) on 70 aerobically trained, overweight, and obese women were examined in a triple-blind, placebo-controlled, clinical study. Subjects were randomly allocated into placebo and experimental groups and consumed either 30 mL/day of CAE or placebo without changing their diet or physical activity over a period of 90 days. Calorie and macronutrient intake and anthropometric indices were measured before and after the intervention. In addition, appetite changes were assessed through a visual analog scale and an ad libitum pizza test. After the intervention, the results showed a significant reduction in appetite levels and carbohydrate intake of the experimental group compared with the placebo group. All of the anthropometric indices were reduced significantly in CAE compared with placebo group (p < 0.01). These preliminary outcomes suggest that a dietary CAE might be effective in weight management of physically active, adult females, reducing their body size and hunger level. Copyright © 2016 John Wiley & Sons, Ltd.

Norrish-Prins reaction as a key step in the synthesis of 14β-hydroxy-5α (or 5β or Δ(5,6))-pregnane derivatives

Numerous bioactive glycosteroids are characterized by aglycones bearing a 14β-hydroxy pregnane skeleton like boucerin and isoramanone. In general, the syntheses of the latter are achieved by acidic hydrolysis of the corresponding glycosteroids. These aglycones were also obtained by a combined Norrish type I-Prins reaction starting from the corresponding 12-keto-pregnane derivatives. However, for the Norrish-Prins reaction, no reports describe the influence of the A/B ring junction (cis or trans or Δ(5,6) double bond) or the influence of the substitution pattern at position 20. Herein, we describe the use of Norrish type I-Prins reactions to synthesize isoramanone and boucerin derivatives and their A/B cis and trans analogs. The influence of the parameters mentioned above is also presented. These studies showed that the A/B ring junction has little influence on the Norrish type I-Prins reaction but that the substitution pattern at position 20 is important. The presence of a dioxolane group induced not only the formation of the desired 14β-hydroxy pregnane derivatives in the highest yields but also the formation of new spiro derivatives.