Aframomum melegueta Seed Extract with Standardized Content of 6-Paradol Reduces Visceral Fat and Enhances Energy Expenditure in Overweight Adults - A Randomized Double-Blind, Placebo-Controlled Clinical Study

PURPOSE

Aframomum melegueta (grains of paradise) seeds have been demonstrated to possess thermogenic potential. However, it is necessary to validate the functional attributes of A. melegueta seed extract in human subjects.

METHODS

In a double-blind, placebo-controlled clinical trial design, we have examined the thermogenic effects of a standardized A. melegueta seed extract (AfperFit). A total of 70 overweight male and female subjects (BMI ≥25.0 to ≤30.0 kg/m²) aged 20-50 years were enrolled and administered with either 250 mg of AfperFit or placebo in capsule form twice daily for 12 weeks. The primary efficacy endpoints included energy expenditure (indirect calorimetry), body composition (dual-energy X-ray absorptiometry (DEXA)) and fat distribution (computed tomography (CT scan)), analyzed at baseline and after 12 weeks of treatment. The effect of intervention on the quality of life was examined using SF-12 questionnaire.

RESULTS

Consumption of AfperFit significantly increased the energy expenditure (p<0.01), visceral fat area (p<0.001) and visceral to subcutaneous fat ratio (p<0.01) compared to placebo group. Consequently, there was significant body weight loss and reduction in BMI of subjects in AfperFit group compared to placebo (p<0.01). The safety evaluation showed that biochemical and hematological parameters were in the normal range. Supplementation of AfperFit was well tolerated during the study and no adverse effects were observed.

CONCLUSION

Overall, this study validates the health benefits of A. melegueta seed extract as fat burner and recommends its use as a functional ingredient to improve the quality of life and general health.

6-Paradol alleviates Diclofenac-induced acute kidney injury via autophagy enhancement-mediated by AMPK/AKT/mTOR and NLRP3 inflammasome pathways

Diclofenac (DIC)-induced acute kidney injury (AKI) causes high morbidity and mortality. With the absence of satisfactory treatment, we investigated the protective effects of 6-Paradol (PDL) against DIC-induced AKI, with focus on renal autophagy and NLRP3 inflammasome pathways . PDL has anti-inflammatory, antioxidant and AMPK-activation properties. PDL was administered to DIC-challenged rats. Nephrotoxicity, oxidative stress, inflammatory, and autophagy markers and histopathological examinations were evaluated. Compared to DIC, PDL restored serum nephrotoxicity, renal oxidative stress and pro-inflammatory markers. PDL almost restored renal architecture, upregulated renal Nrf2 pathway via enhancing Nrf2 mRNA expression and HO-1 levels. PDL suppressed renal NF-κB mRNA expression, and NLRP3 inflammasome pathway expression. Moreover, PDL enhanced renal autophagy through upregulating LC3B, AMPK and SIRT-1, and suppressed mTOR, p-AKT mRNA expressions and phosphorylated-p62 levels. Our study confirmed that autophagy suppression mediates DIC-induced AKI via AMPK/mTOR/AKT and NLRP3-inflammasome pathways. Also, PDL's nephroprotective effects could provide a promising therapeutic approach against DIC-induced AKI.

In vitro experiments of Pediculus humanus capitis (Phthiraptera: Pediculidae) resistance to permethrin and 6-paradol in East Jakarta: Detoxification enzyme activity and electron microscopic changes in lice

Background and Aim:

Pediculus humanus capitis, the human head louse, remains a global health problem. This study evaluated the resistance of head lice to permethrin and 6-paradol mediated by in vitro detoxification enzyme activity experiments and to describe physical changes in the lice using scanning electron microscopy (SEM).

Materials and Methods:

The adult stages of P. h. capitis were collected from patients exposed to 1% permethrin and three different concentrations of 6-paradol (0.00005%, 0.0001%, and 0.00015%) using a filter paper diffusion bioassay. Healthy P. h. capitis adults served as the control. The in vitro bioassays were conducted after 10, 20, 30, and 60 min of exposure. The activities of acetylcholinesterase (AChE), glutathione S-transferase (GST), and oxidase were analyzed. Physical changes in the lice were analyzed using SEM.

Results:

Permethrin and 6-paradol exhibited low toxicity against the lice. At 60 min, 1% permethrin had killed 36.7% of the lice present, while 6-paradol had killed 66.7-86.7%. Permethrin induced significantly elevated AChE, GST, and oxidase activity; 6-paradol also caused significantly elevated AChE, GST, and oxidase activity. Permethrin did not cause any ultrastructural morphological changes on the lice, while 6-paradol severely damaged the head, thorax, respiratory spiracles, and abdomen of the dead lice.

Conclusion:

This in vitro experimental of P. h. capitis is the first study to report P. h. capitis in East Jakarta shows complete resistance to permethrin and 6-paradol, and to describe the associated increase in AChE, GST, and oxidase activity. It was observed that 6-paradol severely damaged the head, thorax, respiratory spiracles, and abdomen of the dead lice.

6-Paradol Acts as a Potential Anti-obesity Vanilloid from Grains of Paradise

SCOPE

Grains of Paradise (GOP), the seeds of Aframomum melegueta, has anti-obesity effects. However, the mechanisms underlying the effects remain unclear.

METHODS AND RESULTS

This study sets up to study the anti-obesity impact and homeostatic effects of 6-paradol, a major vanilloid found in GOP, and investigates the physiological outputs and the lipometabolism-related gene in fat and liver in high-fat-induced obese mice with a comparison with structurally similar vanilloids (6-gingerol and 6-shogaol). The vanilloids are synthesized in adequate quantities for performing animal experiments and orally administered to 6-week-old male mice over 2 weeks. This study found that 6-paradol decreased body weight gain and visceral and subcutaneous fats in 2 weeks, whereas 6-gingerol and 6-shogaol have no effect. Additionally, 6-paradol suppresses the hepatic cholesterol and triglyceride and significantly decreases the gene expression related to fatty acid synthesis, lipid transportation, and adipocyte differentiation in both liver and adipose tissue. Moreover, phosphorylation of AMP-activated protein kinase (AMPK) that greatly contributes to lipometabolism is promoted by 6-gingerol but not 6-paradol.

CONCLUSION

These results suggest that 6-paradol regulates several obesity-related genes in an AMPK-independent manner. Therefore, it could be the principal active vanilloid in GOP giving it anti-obesity properties with a different mechanism.

Protective effect of 6-paradol in acetic acid-induced ulcerative colitis in rats

Background

Ulcerative colitis is a gut inflammatory disorder due to altered immune response to gut microbiome, with interplay of environmental and genetic factors. TNF-α activates inflammatory response through a cascade of immune responses, augmenting pro-inflammatory mediators and proteases, activating chemotaxis, and infiltration of inflammatory cells, leading to ulceration and haemorrhage through cytotoxic reactive oxygen species. 6-Paradol, a dietary component in several plants belonging to the Zingiberaceae family, has shown anti-inflammatory and antioxidant activities. Current study evaluates the effect of 6-paradol in amelioration of ulcerative colitis in rats for the first time.

Methods

6-Paradol (95% purity) was obtained from seeds of Aframomum melegueta. Rats were divided randomly into six groups (n = 8). Group one was administered normal saline; group two was treated with the vehicle only; group three, sulfasalazine 500 mg/kg; and groups four, five, and six, were given 6-paradol (50, 100, 200, respectively) mg/kg orally through gastric gavage for 7 days. Colitis was induced on 4th day by intrarectal administration of 2 ml acetic acid (3%), approximately 3 cm from anal verge. On 8th day, rats were sacrificed, and distal one-third of the colon extending proximally up to 4 cm from anal orifice was taken for biochemical and gross examination. Two centimetres of injured mucosal portion was taken for histopathological investigations. SPSS (ver.26) was used for statistical analysis.

Results

Colonic and serum glutathione (GSH) levels decreased, while colonic and serum malondialdehyde (MDA), colonic myeloperoxidase (MPO) activity, serum interleukin-6 (IL-6), serum tumour necrosis factor-α (TNF-α) levels, and colon weight to length ratio were increased significantly in the colitis untreated group compared to normal control. Treatment with 6-paradol considerably improved all these parameters, especially at a dose of 200 mg/kg (p < 0.001), revealing non-significant differences with sulfasalazine 500 mg/kg and normal control (p = 0.998). Sulfasalazine and 6-paradol in a dose dependent manner also markedly reversed mucosal oedema, atrophy and inflammation, cryptic damage, haemorrhage, and ulceration. There were non-significant differences between low and medium doses and between medium and high doses of 6-paradol for IL-6 and serum MDA levels.

Conclusion

6-Paradol demonstrated protection against acetic acid-induced ulcerative colitis, probably by anti-inflammatory and antioxidant actions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-021-03203-7.

Determination of bioactive nonvolatile ginger constituents in dietary supplements by a rapid and economic HPLC method: Analytical method development and single-laboratory validation

Most of the validated methods for ginger-containing dietary supplements have long run time and low sensitivity and only analyze gingerols and shogaols. 6-Paradol and zingerone become popular in modern dietary supplement industry as bioactive ginger constituents. Therefore, we developed an efficient HPLC-UV/Vis method to analyze all above major constituents. Compared to 282/280 nm used by the current compendial United States Pharmacopeia (USP) monograph method and International Organization for Standardization (ISO) 13685-1997 method, detection wavelength was optimized to 230 nm which showed a higher sensitivity (signal-to-noise ratio) and better peak resolution. For measuring the ginger constituents in AOAC required matrices, the method was demonstrated to be selective, linear (R2 > 0.999), specific, accurate (91.1-103.2% spike recovery rate) and precise (RSDr < 5%, RSDR < 8%). Among 10 commercial ginger-containing samples that we screened using this method, the results were 80-123% of the products' labeling value. The HPLC running time was successfully shortened from 29 min (USP method) and 40 min (ISO method) to 12 min without the need of using an expensive Mass Spectrometer for analyte separation. The method is the first method that meets all AOAC SMPR 2017.12 requirements and therefore has the potential to be adopted as a consensus industrial reference method for meeting FDA's cGMP Compliance for the manufacture and quality control of dietary supplements and ingredients.

6-Paradol and 6-Shogaol, the Pungent Compounds of Ginger, Promote Glucose Utilization in Adipocytes and Myotubes, and 6-Paradol Reduces Blood Glucose in High-Fat Diet-Fed Mice

The anti-diabetic activity of ginger powder (Zingiber officinale) has been recently promoted, with the recommendation to be included as one of the dietary supplements for diabetic patients. However, previous studies presented different results, which may be caused by degradation and metabolic changes of ginger components, gingerols, shogaols and paradols. Therefore, we prepared 10 ginger active components, namely 6-, 8-, 10-paradols, 6-, 8-, 10-shogaols, 6-, 8-, 10-gingerols and zingerone, and evaluated their anti-hyperglycemic activity. Among the tested compounds, 6-paradol and 6-shogaol showed potent activity in stimulating glucose utilization by 3T3-L1 adipocytes and C2C12 myotubes. The effects were attributed to the increase in 5' adenosine monophosphate-activated protein kinase (AMPK) phosphorylation in 3T3-L1 adipocytes. 6-Paradol, the major metabolite of 6-shogaol, was utilized in an in vivo assay and significantly reduced blood glucose, cholesterol and body weight in high-fat diet-fed mice.