Chili pepper as a body weight-loss food

Effects of Leaf Extracts from Genetic Resource of Capsicum spp. on Neuroprotection and Anti-Neuroinflammation in HT22 and in BV2 Cells

To develop functional varieties of Capsicum spp. leaves, 40 genetic resources were collected and extracted with 30% aqueous-fermented ethanol. We investigated the protective effects of extracts from 40 genetic resources of Capsicum spp. on glutamate-induced HT22 and LPS-induced BV2 cells. The results showed that the five extracts exhibited cell-protective activities. We also investigated the anti-inflammatory effects of these five extracts on LPS-induced BV2 cell neuroinflammation and found that 23OM18 exhibited superior anti-inflammatory effects. We further investigated the protective activity and anti-inflammatory mechanisms of 23OM18 in these two cell models. In addition, the profiles of 16 metabolites were compared between the representative accessions and among the five genetic resources using ultra-high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS). The results showed that 23OM18 protected HT22 cells by inhibiting reactive oxygen species generation and regulating the MAPK-JNK signaling pathway, thereby reducing LPS-induced BV2 cell neuroinflammation by regulating the NF-κB and MAPK signaling pathways. Based on these results, 23OM18 has the potential to be developed as a functional food for the treatment of neurodegenerative diseases.

Cannabidiol modulates contextual fear memory consolidation in animals with experimentally induced type-1 diabetes mellitus

OBJECTIVES

In view of the neuroprotective characteristic of cannabidiol (CBD) and its beneficial action on aversive memory in non-diabetic animals, we aimed to investigate in animals with experimentally induced type-1 diabetes mellitus (T1DM) whether CBD treatment would be able to impair the contextual fear memory consolidation, its generalisation and whether the effect would be lasting. We also investigated the CBD effect on anxiety-like responses.

METHODS

After T1DM induction, animals received single or more prolonged treatment with CBD and were submitted to the contextual fear conditioning test. As expression of activity-regulated cytoskeletal-associated (Arc) protein is necessary for memory consolidation, we evaluated its expression in the dorsal hippocampus (DH). For evaluating anxiety-related responses, animals were submitted to the elevated plus maze test (EPMT), in which the time and number of entries in the open arms were used as anxiety index.

RESULTS

A single injection of CBD impaired the contextual fear memory consolidation and its generalisation, which was evaluated by exposing the animal in a neutral context. This single injection was able to reduce the elevated expression of Arc in the DH from these animals. Interestingly, more prolonged treatment with CBD also impaired the persistence of context-conditioned fear memory and induced an anxiolytic-like effect, as the treated group spent more time in the open arms of the EPMT.

CONCLUSION

CBD interferes with contextual fear memory and the dosage regimen of treatment seems to be important. Moreover, we cannot rule out the involvement of emotional aspects in these processes related to fear memory.

Association between Variants of the TRPV1 Gene and Body Composition in Sub-Saharan Africans

In humans, the transient receptor potential vanilloid 1 (TRPV1) gene is activated by exogenous (e.g., high temperatures, irritating compounds such as capsaicin) and endogenous (e.g., endocannabinoids, inflammatory factors, fatty acid metabolites, low pH) stimuli. It has been shown to be involved in several processes including nociception, thermosensation, and energy homeostasis. In this study, we investigated the association between TRPV1 gene variants, sensory perception (to capsaicin and PROP), and body composition (BMI and bioimpedance variables) in human populations. By comparing sequences deposited in worldwide databases, we identified two haplotype blocks (herein referred to as H1 and H2) that show strong stabilizing selection signals (MAF approaching 0.50, Tajima's D > +4.5) only in individuals with sub-Saharan African ancestry. We therefore studied the genetic variants of these two regions in 46 volunteers of sub-Saharan descent and 45 Italian volunteers (both sexes). Linear regression analyses showed significant associations between TRPV1 diplotypes and body composition, but not with capsaicin perception. Specifically, in African women carrying the H1-b and H2-b haplotypes, a higher percentage of fat mass and lower extracellular fluid retention was observed, whereas no significant association was found in men. Our results suggest the possible action of sex-driven balancing selection at the non-coding sequences of the TRPV1 gene, with adaptive effects on water balance and lipid deposition.

Capsaicin induces ATP-dependent thermogenesis via the activation of TRPV1/β3-AR/α1-AR in 3T3-L1 adipocytes and mouse model

Capsaicin (CAP) is a natural bioactive compound in chili pepper that activates the transient receptor potential vanilloid subfamily 1 (TRPV1) and is known to stimulate uncoupling protein 1 (UCP1)-dependent thermogenesis. However, its effect on ATP-dependent thermogenesis remains unknown. In this study, we employed qRT-PCR, immunoblot, staining method, and assay kit to investigate the role of CAP on ATP-dependent thermogenesis and its modulatory roles on the TRPV1, β3-adrenergic receptor (β3-AR), and α1-AR using in vitro and in vivo models. The studies showed that CAP treatment in high-fat diet-induced obese mice resulted in lower body weight gain and elevated ATP-dependent thermogenic effectors' protein and gene expression through ATP-consuming calcium and creatine futile cycles. In both in vitro and in vivo experiments, CAP treatment elevated the protein and gene expressions of sarcoendoplasmic/endoplasmic reticulum calcium ATPase 2 (SERCA2), ryanodine receptor 2 (RYR2), creatine kinase B (CKB), and creatine kinase mitochondrial 2 (CKMT2) mediated by the activation of β3-AR, α1-AR, and TRPV1. Our study showed that CAP increased intracellular Ca2+ levels and the expression of voltage-dependent anion channel (VDAC) and mitochondrial calcium uniporter (MCU) which indicates that increased mitochondrial Ca2+ levels lead to increased expression of oxidative phosphorylation protein complexes as a result of ATP-futile cycle activation. A mechanistic study in 3T3-L1 adipocytes revealed that CAP induces UCP1- and ATP-dependent thermogenesis mediated by the β3-AR/PKA/p38MAPK/ERK as well as calcium-dependent α1-AR/TRPV1/CaMKII/AMPK/SIRT1 pathway. Taken together, we identified CAP's novel functional and modulatory roles in UCP1- and ATP-dependent thermogenesis, which is important for developing therapeutic strategies for combating obesity and metabolic diseases.

A natural sustained-intestinal release formulation of red chili pepper extracted capsaicinoids (Capsifen®) safely modulates energy balance and endurance performance: a randomized, double-blind, placebo-controlled study

Introduction

Overweight and obesity are major public health concerns, with a sharp increase in prevalence over the last few decades. The primary cause is an imbalance between calorie intake and expenditure due to a rise in calorie-rich processed food and reduced physical activity. Energy balance in humans involves complex processes including thermogenesis, a crucial factor in regulating energy expenditure.

Methods

In this randomized, double-blinded, placebo-controlled three-arm three-sequence study, we investigated the efficacy of Capsifen® (CapF), a pungency-masked sustained-intestinal release formulation of red chili extract, on energy expenditure, fat oxidation, and endurance using the Quark C-PET system in healthy overweight participants, with and without exercise. In the study, 105 healthy participants were randomized to receive either placebo, CapF 100 mg/day, or CapF 200 mg/day for 28 days.

Results

CapF demonstrated a dose-dependent response to increased energy expenditure and fatty acid oxidation with a concomitant reduction in body weight. Both CapF 100 and CapF 200 also increased the time to exhaustion.

Discussion

These results demonstrate the plausible efficacy of CapF in energy expenditure and physical performance in otherwise healthy adults who have a high body mass index.

Clinical trial registration

https://ctri.nic.in/Clinicaltrials/pmaindet2.php?EncHid=MjQzNTg=&Enc=&userName=CTRI/2018/04/013157 dated 04 October 2018.

Brown Adipose Tissue, Batokines, and Bioactive Compounds in Foods: An Update

The discovery of metabolically active brown adipose tissue (BAT) in human adults and the worldwide increase in obesity and obesity-related chronic noncommunicable diseases (NCDs) has made BAT a therapeutic target in the last two decades. The potential of BAT to oxidize fatty acids rapidly and increase energy expenditure inversely correlates with adiposity, insulin and glucose resistance, and cardiovascular and metabolic diseases. Currently, BAT is recognized by a new molecular signature; several BAT-derived molecules that act positively on target tissues have been identified and collectively called batokines. Bioactive compounds present in foods are endowed with thermogenic properties that increase BAT activation signaling. Understanding the mechanisms that lead to BAT activation and the batokines secreted by it within the thermogenic state is fundamental for its recruitment and management of obesity and NCDs. This review contributes to recent updates on the morphophysiology of BAT, its endocrine role in obesity, and the main bioactive compounds present in foods involved in classical and nonclassical thermogenic pathways activation.

The role of TRPV ion channels in adipocyte differentiation: What is the evidence?

Obesity is a complex disorder, and the incidence of obesity continues to rise at an alarming rate worldwide. In particular, the growing incidence of overweight and obesity in children is a major health concern. However, the underlying mechanisms of obesity remain unclear and the efficacy of several approaches for weight loss is limited. As an important calcium-permeable temperature-sensitive cation channel, transient receptor potential vanilloid (TRPV) ion channels directly participate in thermo-, mechano-, and chemosensory responses. Modulation of TRPV ion channel activity can alter the physiological function of the ion channel, leading to neurodegenerative diseases, chronic pain, cancer, and skin disorders. In recent years, increasing studies have demonstrated that TRPV ion channels are abundantly expressed in metabolic organs, including the liver, adipose tissue, skeletal muscle, pancreas, and central nervous system, which has been implicated in various metabolic diseases, including obesity and diabetes mellitus. In addition, as an important process for the pathophysiology of adipocyte metabolism, adipocyte differentiation plays a critical role in obesity. In this review, we focus on the role of TRPV ion channels in adipocyte differentiation to broaden the ideas for prevention and control strategies for obesity.

Bioactive Properties, Bioavailability Profiles, and Clinical Evidence of the Potential Benefits of Black Pepper (Piper nigrum) and Red Pepper (Capsicum annum) against Diverse Metabolic Complications

The consumption of food-derived products, including the regular intake of pepper, is increasingly evaluated for its potential benefits in protecting against diverse metabolic complications. The current study made use of prominent electronic databases including PubMed, Google Scholar, and Scopus to retrieve clinical evidence linking the intake of black and red pepper with the amelioration of metabolic complications. The findings summarize evidence supporting the beneficial effects of black pepper (Piper nigrum L.), including its active ingredient, piperine, in improving blood lipid profiles, including reducing circulating levels of total cholesterol, low-density lipoprotein cholesterol, and triglycerides in overweight and obese individuals. The intake of piperine was also linked with enhanced antioxidant and anti-inflammatory properties by increasing serum levels of superoxide dismutase while reducing those of malonaldehyde and C-reactive protein in individuals with metabolic syndrome. Evidence summarized in the current review also indicates that red pepper (Capsicum annum), together with its active ingredient, capsaicin, could promote energy expenditure, including limiting energy intake, which is likely to contribute to reduced fat mass in overweight and obese individuals. Emerging clinical evidence also indicates that pepper may be beneficial in alleviating complications linked with other chronic conditions, including osteoarthritis, oropharyngeal dysphagia, digestion, hemodialysis, and neuromuscular fatigue. Notably, the beneficial effects of pepper or its active ingredients appear to be more pronounced when used in combination with other bioactive compounds. The current review also covers essential information on the metabolism and bioavailability profiles of both pepper species and their main active ingredients, which are all necessary to understand their potential beneficial effects against metabolic diseases.

Peppers and their constituents against obesity

Phytotherapy can be an efficient tool for prevention and treatment of disorders including obesity. The purpose of this narrative review is to summarize the available knowledge concerning the positive effects of peppers (Capsicum spp.) and their alkaloid capsaicin on human health, in particular on fat and obesity. Search for literature was performed in Medline/Pubmed, Web of Science and SCOPUS databases between the year 2000 and 2023. Words used to search were pepper, Capsicum, capsaicin, review, obesity, fat, weight loss and mechanisms. The available data demonstrate that both pepper extract and capsaicin can positively influence human health and treat several disorders. Moreover, they can reduce fat storage affecting brain centres responsible for the sensation of hunger, nutrient uptake by gastrointestinal tract, state of adipocytes, increase in carbohydrate and fat oxidation, metabolism and thermogenesis and other mechanisms. Therefore, despite some possible limitations, these substances could be useful for treatment of obesity.

Beneficial Effects of Fermentation of Red Chili Pepper Using Lactococcus lactis subs. Cremoris RPG-HL-0136 in High-Fat Diet-Induced Obese Mice

Red chili pepper is a beneficial natural spicy food that has antiobesity and antitype II diabetes effects, but it is not conducive to in-depth research as a dietary strategy to treat obesity. This study aims to investigate the beneficial effects of red chili pepper, fermented with a novel Lactococcus lactis subs. cremoris RPG-HL-0136. LC-MS/MS analysis is conducted to detect the content of capsaicin and dihydrocapsaicin, and no significant difference is observed between the nonfermented red chili pepper (NFP) (W/W) and the prepared L. lactis subs. cremoris RPG-HL-0136-fermented chili mixture (LFP). After establishing a high-fat diet-induced obese type II diabetic mouse model, the effects on weight gain, weight loss of liver and testicular fat, total cholesterol, triglyceride, fasting glucose, insulin, and homeostatic model assessment for insulin resistance in LFP were evaluated to be better than those in NFP following 10 weeks of interventions. All animal experiments were approved by the Institutional Animal Care and Use Committee of Xinxiang medical university. NFP and LFP could increase the expression of transient receptor potential vanilloid subfamily 1, peroxisome proliferator-activated receptor-alpha and caspase-2 in the high-fat mice. Compared with unfermented red chili pepper, the fermented red chili pepper complex significantly reduced LPS, tumor necrosis factor-alpha, and interleukin-6 in serum (P < .05). Intake of LFP significantly increased the expression of claudin-1 and occludin in the colon of the high-fat mice (P < .05), and there was no damage to the stomach and colon. This study provides scientific evidence that red chili pepper, fermented with L. lactis subs. cremoris RPG-HL-0136, may be beneficial for future treatment of obesity and accompanying diabetes. (IACUC.No.XYLL-20200019).

Cellular responses to 8-methyl nonanoic acid, a degradation by-product of dihydrocapsaicin, in 3T3-L1 adipocytes

BACKGROUND

Capsaicinoids, such as dihydrocapsaicin (DHC), exert the health-promoting effects of chili peppers on energy metabolism. The metabolic responses to capsaicinoids are primarily mediated through transient receptor potential cation channel subfamily V member 1 (TRPV1). However, the varying contributions of their metabolites to beneficial health outcomes remain unclear. 8-methyl nonanoic acid (8-MNA), a methyl-branched medium chain fatty acid (MCFA), is an in vivo degradation by-product of DHC. Since MCFAs have emerged as metabolic modulators in adipocytes, here we examined various cellular responses to 8-MNA in 3T3-L1 adipocytes.

METHODS

The viability of 3T3-L1 adipocytes exposed to various concentrations of 8-MNA was assessed by the Calcein AM assay. Biochemical assays for lipid accumulation, AMP-activated protein kinase (AMPK) activity, lipolysis and glucose uptake were performed in 3T3-L1 adipocytes treated with 8-MNA during 48-h nutrient starvation or 5-day maturation.

RESULTS

8-MNA caused no impact on cell viability. During nutrient starvation, 8-MNA decreased lipid amounts in association with AMPK activation, a molecular event that suppresses lipogenic processes. Moreover, 3T3-L1 adipocytes that were treated with 8-MNA during 5-day maturation exhibited a reduced lipolytic response to isoproterenol and an increased glucose uptake when stimulated with insulin.

CONCLUSIONS

These results suggest that 8-MNA derived from DHC modulates energy metabolism in adipocytes and also support the idea that the metabolic benefits of chili consumption are partly attributable to 8-MNA.

Spicy Food and Chili Peppers and Multiple Health Outcomes: Umbrella Review

Spicy foods and chili peppers contain the primary ingredient capsaicin, which has potential health benefits. However, their efficacy in some health outcomes is also fiercely disputed, and some side effects have been confirmed. To assess the quality and strength of the associations between spicy food and chili pepper consumption and different health outcomes. An umbrella review is performed in humans. Eleven systematic reviews and meta-analyses with a total of 27 findings are identified. The health effect of consuming spicy food and chili peppers is unclear. Furthermore, the characteristics and context of different world regions and populations should be carefully considered. Direct correlations exist in esophageal cancer, gastric cancer, and gallbladder cancer. However, negative connections are reported in metabolism, mortality, and cardiovascular disease. Dose-response analysis reveals a significant nonlinear relationship between gastric cancer risk and capsaicin intake. The consumption of spicy foods and chili peppers is typically safe. However, high-quality proof is available to confirm this conclusion.

Preference for Stronger Taste Associated with a Higher Risk of Hypertension: Evidence from a Cross-Sectional Study in Northwest China

Background. Dietary modulation is a primary lifestyle approach for reducing the risk of hypertension. However, evidence of the potential role that a dietary taste preference plays in the risk of hypertension remains limited. Methods. A cross-sectional analysis was conducted based on the Shaanxi baseline survey of the Regional Ethnic Cohort Study. We used self-reported salt consumption and intensity preferences for sourness and spiciness to calculate the taste preference score, which was categorized into bland, moderate, and strong. A generalized linear mixed model and quantile regression were performed to estimate associations between taste preferences and hypertension/blood pressure. Results. Among 27,233 adults, 72.2% preferred a moderate taste and 21.4% preferred a strong taste. Compared with a bland taste, a stronger taste preference might be associated with a higher risk of hypertension (adjusted OR for a moderate taste = 1.25, 95% CI: 1.06, 1.49; adjusted OR for a strong taste = 1.41, 95% CI: 1.15, 1.71; Ptrend = 0.002), especially in females (adjusted OR for a moderate taste = 1.43, 95% CI: 1.24, 1.66; adjusted OR for a strong taste = 1.55, 95% CI: 1.32, 1.83; $P_{\mathrm{t}\mathrm{r}\mathrm{e}\mathrm{n}\mathrm{d}}<0.001$ ). Quantile regression showed that the taste preference was positively associated with diastolic blood pressure (DBP) (P5-P80) in females, with an average increase of 3.31 mmHg for a strong taste (β = 3.31, $P<0.001$ ) and 1.77 mmHg for a moderate taste (β = 1.77, P = 0.008). Conclusions. A preference for stronger multitastes of salty, sour, and spicy might be associated with a higher risk of hypertension, especially in females. This relationship possibly occurs through increasing DBP. Dietary modulation with the promotion of a bland taste is encouraged.

Detection of indigenous gut bacteria related to red chilli pepper (Capsicum annuum) in murine caecum and human faecal cultures

BACKGROUND

Red chilli pepper (Capsicum annuum; RP) is a popular spice containing the active compound capsaicin. Indigenous gut bacteria and metabolism can affect host health. The functions of capsaicin, including the regulation of metabolic health and anti-oxidant properties, may be correlated with the gut microbiota.

METHODS

To identify indigenous gut bacteria that are responsive to RP, Institute of Cancer Research mice fed a diet with no fibre or with 5% (w/w) RP for 14 days. Additionally, human stool samples collected from four healthy volunteers were incubated without (control) or with 2% (w/v) RP at 37 °C for 24 h. Microbiota in murine caecal samples and human faecal cultures were analysed using 16S rRNA (V4) amplicon sequencing.

RESULTS

Compared with the microbiota in mice fed no-fibre diets, Lachnospiraceae spp.-, Muribaculaceae spp.-, and Phacaeicola vulgatus-like bacteria were defined as murine RP-responsive indigenous gut bacteria (RP-RIB). In the human faecal cultures, acetate and propionate levels were higher in RP cultures than in the control cultures. Subdoligranulum spp.-, Blautia spp.-, Faecalibacterium prausnitzii-, P. vulgatus-, and Prevotella copri-like bacteria were defined as human RP-RIB. Compared with control culture Fe-reducing power was increased in the culture with RP.

CONCLUSION

RP increases the amount of short-chain fatty acid-producing bacteria and beneficial gut bacteria in mouse and human faecal cultures. Overall, RP could have a positive effect on the host by altering the gut microbiota.

Fruity, sticky, stinky, spicy, bitter, addictive, and deadly: evolutionary signatures of metabolic complexity in the Solanaceae

Covering: 2000-2022Plants collectively synthesize a huge repertoire of metabolites. General metabolites, also referred to as primary metabolites, are conserved across the plant kingdom and are required for processes essential to growth and development. These include amino acids, sugars, lipids, and organic acids. In contrast, specialized metabolites, historically termed secondary metabolites, are structurally diverse, exhibit lineage-specific distribution and provide selective advantage to host species to facilitate reproduction and environmental adaptation. Due to their potent bioactivities, plant specialized metabolites attract considerable attention for use as flavorings, fragrances, pharmaceuticals, and bio-pesticides. The Solanaceae (Nightshade family) consists of approximately 2700 species and includes crops of significant economic, cultural, and scientific importance: these include potato, tomato, pepper, eggplant, tobacco, and petunia. The Solanaceae has emerged as a model family for studying the biochemical evolution of plant specialized metabolism and multiple examples exist of lineage-specific metabolites that influence the senses and physiology of commensal and harmful organisms, including humans. These include, alcohols, phenylpropanoids, and carotenoids that contribute to fruit aroma and color in tomato (fruity), glandular trichome-derived terpenoids and acylsugars that contribute to plant defense (stinky & sticky, respectively), capsaicinoids in chilli-peppers that influence seed dispersal (spicy), and steroidal glycoalkaloids (bitter) from Solanum, nicotine (addictive) from tobacco, as well as tropane alkaloids (deadly) from Deadly Nightshade that deter herbivory. Advances in genomics and metabolomics, coupled with the adoption of comparative phylogenetic approaches, resulted in deeper knowledge of the biosynthesis and evolution of these metabolites. This review highlights recent progress in this area and outlines opportunities for - and challenges of-developing a more comprehensive understanding of Solanaceae metabolism.

What Is the Current Direction of the Research on Carotenoids and Human Health? An Overview of Registered Clinical Trials

Carotenoids have been the object of numerous observational, pre-clinical and interventional studies focused on elucidating their potential impacts on human health. However, the large heterogeneity among the trials, in terms of study duration and characteristics of participants, makes any conclusion difficult to draw. The present study aimed to explore the current carotenoid research trends by analyzing the characteristics of the registered clinical trials. A total of 193 registered trials on ClinicalTrials.gov and ISRCTN were included in the revision. Eighty-three studies were performed with foods, one-hundred-five with food supplements, and five with both. Among the foods tested, tomatoes and tomato-based foods, and eggs were the most studied. Lutein, lycopene, and astaxanthin were the most carotenoids investigated. Regarding the goals, 52 trials were focused on studying carotenoids’ bioavailability, and 140 studies investigated the effects of carotenoids on human health. The main topics included eye and cardiovascular health. Recently, the research has focused also on two new topics: cognitive function and carotenoid–gut microbiota interactions. However, the current research on carotenoids is still mostly focused on the bioavailability and metabolism of carotenoids from foods and food supplements. Within this context, the impacts/contributions of food technologies and the development of new carotenoid formulations are discussed. In addition, the research is still corroborating the previous findings on vision and cardiovascular health. Much attention has also been devoted to new research areas, such as the carotenoid–microbiota interactions, which could contribute to explaining the metabolism and the health effects of carotenoids; and the relation between carotenoids and cognitive function. However, for these topics the research is still only beginning, and further studies are need.

Chili pepper intake and all-cause and disease-specific mortality

Background: Chili pepper has been used for the treatment and prevention of multiple diseases. This may be due to its abundance of bioactive components, such as carotenoids, which are well known for their antioxidant properties. To date, several prospective cohort studies have examined the association between chili pepper intake and mortality, but the results have not been consistent. This study aimed to clarify the association between chili pepper intake and all-cause and disease-specific mortality using a meta-analysis. Methods: PubMed, Embase, and ISI Web of Science databases were searched up to December 20, 2020, and reference lists of included studies were manually reviewed. All prospective cohort studies on the association between chili pepper intake and all-cause, cardiovascular disease (CVD)-specific, and cancer-specific mortality were included in this study. Pooled hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated in the meta-analysis. Between-study heterogeneity was assessed using I² statistic and Q test. Results: A total of 4 cohort studies (N=564,748; all four studies had adjusted for important potential confounders such as demographic variables, dietary intake, and physical activity) were ultimately included in this meta-analysis. Among them, 31,527 died due to all causes, 10,184 died due to CVD, and 9,868 died due to cancer. Compared to none or rare consumption of chili pepper, consumption of chili pepper (ever or more than once a week) could significantly reduce the risk of all-cause mortality (summary adjusted HR: 0.87, 95% CI: 0.85, 0.90), CVD-specific mortality (summary adjusted HR: 0.89, 95% CI: 0.85, 0.93), and cancer-specific mortality (summary adjusted HR: 0.92, 95% CI: 0.88, 0.97). There was no significant between-study heterogeneity in the analyses (all-cause mortality: I²=0.7%, P=0.389; CVD-specific mortality: I²=21.8%, P=0.280; cancer-specific mortality: I²=0.0%, P=0.918). Conclusions: The present meta-analysis confirmed that chili pepper intake could reduce the risk of all-cause, CVD-specific, and cancer-specific mortality, suggesting that chili pepper may be a beneficial ingredient in the diets in prolonging life.

Interactions between Food and Drugs, and Nutritional Status in Renal Patients: A Narrative Review

Drugs and food interact mutually: drugs may affect the nutritional status of the body, acting on senses, appetite, resting energy expenditure, and food intake; conversely, food or one of its components may affect bioavailability and half-life, circulating plasma concentrations of drugs resulting in an increased risk of toxicity and its adverse effects, or therapeutic failure. Therefore, the knowledge of these possible interactions is fundamental for the implementation of a nutritional treatment in the presence of a pharmacological therapy. This is the case of chronic kidney disease (CKD), for which the medication burden could be a problem, and nutritional therapy plays an important role in the patient’s treatment. The aim of this paper was to review the interactions that take place between drugs and foods that can potentially be used in renal patients, and the changes in nutritional status induced by drugs. A proper definition of the amount of food/nutrient intake, an adequate definition of the timing of meal consumption, and a proper adjustment of the drug dosing schedule may avoid these interactions, safeguarding the quality of life of the patients and guaranteeing the effectiveness of drug therapy. Hence, a close collaboration between the nephrologist, the renal dietitian, and the patient is crucial. Dietitians should consider that food may interact with drugs and that drugs may affect nutritional status, in order to provide the patient with proper dietary suggestions, and to allow the maximum effectiveness and safety of drug therapy, while preserving/correcting the nutritional status.

Metabolic shifts during fruit development in pungent and non-pungent peppers

Fruit pungency is caused by the accumulation of capsaicinoids, secondary metabolites whose relation to primary metabolism remains unclear. We have selected ten geographically diverse accessions of Capsicum chinense Jacq with different pungency levels. A detailed metabolic profile was conducted in the fruit placenta and pericarp at 20, 45, and 60 days after anthesis aiming at increasing our understanding of the metabolic changes in these tissues across fruit development and their potential connection to capsaicin metabolism. Overall, despite the variation in fruit pungency among the ten accessions, the composition and metabolite levels in both placenta and pericarp were uniformly stable across accessions. Most of the metabolite variability occurred between the fruit developmental stages rather than among the accessions. Interestingly, different metabolite adjustments in the placenta were observed among pungent and non-pungent accessions, which seem to be related to differences in the genetic background. Furthermore, we observed high coordination between metabolites and capsaicin production in C. chinense fruits, suggesting that pungency in placenta is adjusted with primary metabolism.

Oral Capsaicinoid Administration Alters the Plasma Endocannabinoidome and Fecal Microbiota of Reproductive-Aged Women Living with Overweight and Obesity

Capsaicinoids, the pungent principles of chili peppers and prototypical activators of the transient receptor potential of the vanilloid type-1 (TRPV1) channel, which is a member of the expanded endocannabinoid system known as the endocannabinoidome (eCBome), counteract food intake and obesity. In this exploratory study, we examined the blood and stools from a subset of the participants in a cohort of reproductive-aged women with overweight/obesity who underwent a 12-week caloric restriction of 500 kcal/day with the administration of capsaicinoids (two capsules containing 100 mg of a capsicum annuum extract (CAE) each for a daily dose of 4 mg of capsaicinoids) or a placebo. Samples were collected immediately before and after the intervention, and plasma eCBome mediator levels (from 23 participants in total, 13 placebo and 10 CAE) and fecal microbiota taxa (from 15 participants in total, 9 placebo and 6 CAE) were profiled using LC-MS/MS and 16S metagenomic sequencing, respectively. CAE prevented the reduced caloric-intake-induced decrease in beneficial eCBome mediators, i.e., the TRPV1, GPR119 and/or PPARα agonists, N-oleoyl-ethanolamine, N-linoleoyl-ethanolamine and 2-oleoyl-glycerol, as well as the anti-inflammatory N-acyl-ethanolamines N-docosapentaenyl-ethanolamine and N-docosahexaenoyl-ethanolamine. CAE produced few but important alterations in the fecal microbiota, such as an increased relative abundance of the genus Flavonifractor, which is known to be inversely associated with obesity. Correlations between eCBome mediators and other potentially beneficial taxa were also observed, thus reinforcing the hypothesis of the existence of a link between the eCBome and the gut microbiome in obesity.

Long-Term Chili Monoculture Alters Environmental Variables Affecting the Dominant Microbial Community in Rhizosphere Soil

Continuous cropping negatively affects soil fertility, physicochemical properties and the microbial community structure. However, the effects of long-term chili monoculture on the dominant microbial community assembly are not known. In this study, the impact of long-term chili monoculture on the correlation between the dominant microbial community and soil environmental variables was assessed. The results indicated that increasing duration of chili monoculture generated significant changes in soil nutrients, soil aggregates and soil enzymes: nutrient contents increased overall, mechanically stable macroaggregates increased and microaggregates decreased, water-stable macroaggregates and microaggregates decreased, β-glucosidase decreased nonlinearly, and nitrate reductase and alkaline phosphatase activities showed a nonlinear increase. Moreover, an increasing number of years of chili monoculture also affected the structure of the dominant microbiota, with substantial changes in the relative abundances of 11 bacterial and fungal genera. The drivers of the dominant microbial community assembly in rhizosphere soil were soil moisture, abiotic nitrogen, pH and salt.

Accumulating evidence to support the safe and efficacious use of a proprietary blend of capsaicinoids in mediating risk factors for obesity

Obesity is a significant public health concern, and finding safe and effective means for combating this condition is needed. This study investigates the safety and efficacy of supplementation of a blend of capsaicinoids on weight gain, fat mass, and blood chemistry in a high-fat diet (HFD) model of obesity in mice and on adipocyte differentiation and gene expression in 3T3-L1 preadipocytes. High-fat diet (HFD)-fed mice were treated with a proprietary capsaicinoid concentrate (Capsimax®; OmniActive Health Technologies Ltd., India) and compared to orlistat (ORL) and normal chow-fed mice (NC). Mice fed a high-fat diet showed significantly lower weight gain upon Capsimax® (CAP) administration than their HFD counterparts and similar to that observed with ORL animals. In addition, CAP decreased the high-fat diet-induced increases in adipose tissue and epididymal fat pad mass and hypertrophy after 52 days of treatment. Both the CAP and ORL groups had increased plasma concentrations of leptin. CAP extracts decreased triacylglycerol content in 3T3-L1 preadipocytes and decreased markers of adipogenesis including peroxisome proliferator-activated receptor (PPAR-ɣ) and fatty acid-binding protein 4 (FABP4). Expression of genes involved in lipogenesis such as stearoyl-CoA desaturase (SCD) and fatty acid synthase (FSN) was decreased by CAP in a dose-dependent manner. Thermogenic genes and markers of brown adipose tissue including uncoupling protein 1 (UCP1) and PR domain-containing 16 (Prdm16) were induced by CAP in the preadipocyte cells. These in vivo and in vitro data support that this proprietary capsaicinoid concentrate reduces weight gain and adiposity at least in part through decreasing lipogenesis and increasing thermogenesis.

Consumption of chilies and sweet peppers is associated with lower risk of sarcopenia in older adults

Background: Sarcopenia is an aging-related loss of muscle mass and function, which induces numerous adverse outcomes. Capsaicin and capsiate, separately extracted from chilies and sweet peppers, have the potential to induce muscle hypertrophy via activation of transient receptor potential vanilloid 1. The present study aimed to investigate whether chili and sweet pepper consumption are related to sarcopenia in the elderly general population.

Methods: A cross-sectional study with 2,451 participants was performed. Dietary chili and sweet pepper consumption were assessed using a validated self-administered food frequency questionnaire. Sarcopenia was defined according to the consensus of the Asian Working Group for Sarcopenia. Logistic regressions were performed to measure the effect of chili and sweet pepper consumption on sarcopenia.

Results: The prevalence of sarcopenia was 16.1%. After adjustment for potential confounding variables, the odds ratios (95% confidence intervals) for sarcopenia across chili and sweet pepper consumption categories were 1.00 (reference) for almost never, 0.73 (0.55, 0.97) and 0.73 (0.56, 0.96) for ≤1 time/week, 0.60 (0.39, 0.90) and 0.66 (0.45, 0.95) for ≥2-3 times/week (both P for trend <0.01), respectively.

Conclusion: The present study showed that higher consumption of chilies and sweet peppers was related to a lower risk of sarcopenia in older adults.

Effects of gastrointestinal delivery of non-caloric tastants on energy intake: a systematic review and meta-analysis

Purpose

Taste receptors are expressed throughout the gastrointestinal tract. The activation of post-oral taste receptors using tastants could provide a non-invasive treatment option in combating the obesity epidemic. The aim of this review was to examine the effect of post-oral delivery of non-caloric tastants on eating behavior reflected by primary outcome energy intake and secondary outcomes GI symptoms and perceptions and potential underlying mechanisms. This review was conducted according to the PRISMA guidelines for systematic reviews.

Methods

A systematic literature search of the Cochrane, PubMed, Embase, and Medline databases was performed. This systematic review and meta-analysis was registered in the PROSPERO database on 26 February 2020 (ID: CRD42020171182). Two researchers independently screened 11,912 articles and extracted information from 19 articles. If at least two studies investigated the effect of the same taste compound on primary outcome energy intake, a meta-analysis was performed to determine pooled effect sizes.

Results

Nineteen papers including healthy volunteers were included. In the 19 papers analyzed, effects of various tastants were investigated in healthy volunteers. Most extensively investigated were bitter tastants. The meta-analysis of effects of bitter tastants showed a significant reduction in energy intake of 54.62 kcal (95% CI − 78.54 to − 30.69, p = 0.0014).

Conclusions

Bitter stimuli are most potent to influence eating behavior. Energy intake decreased after post-oral delivery of bitter tastants. This highlights the potential of a preventive role of bitter tastants in battling the obesity epidemic.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00394-021-02485-4.

Enhancement of Lipolysis in 3T3-L1 Adipocytes by Nitroarene Capsaicinoid Analogs

Transient receptor potential vanilloid 1 (TRPV1) activation by capsaicin binding increased intracellular calcium influx and stimulated adipocyte-to-adipocyte communication, leading to lipolysis. Generally, enhancement of π-stacking capabilities improves certain binding interactions. Notably, nitroarenes exhibit strong binding interactions with aromatic amino acid side chains in proteins. New capsaicinoid analogs were designed by substitution of the OCH3 group with a nitrogen dioxide (NO2) group on the vanillyl ring to investigate how π-stacking interactions in capsaicinoid analogs contribute to lipolysis. Capsaicinoid analogs, nitro capsaicin (5), and nitro dihydrocapsaicin (6) were prepared in moderate yields via coupling of a nitroaromatic amine salt and fatty acids. Oil Red O staining and triglyceride assays with 10 µM loading of capsaicin (CAP), dihydrocapsaicin (DHC), 5, and 6 were performed to investigate their effect on lipolysis in 3T3-L1 adipocytes. Both assay results indicated that 5 and 6 decreased lipid accumulation by 13.6% and 14.7%, respectively, and significantly reduced triglyceride content by 26.9% and 28.4%, respectively, in comparison with the control experiment. Furthermore, the decrease in triglyceride content observed in response to nitroarene capsaicinoid analogs was approximately 2-folds higher than that of CAP and DHC. These results arose from the NO2 group augmented π-π stacking with Tyr511 and the attractive charge interaction with Glu570 affecting binding interactions with TRPV1 receptors.

Sex differences in changes in BMI and blood pressure in Chinese school-aged children during the COVID-19 quarantine

There may be sex differences in BMI and blood pressure levels in school-age children, especially in the face of lifestyle changes. This study aimed to explore sex differences in changes in BMI and blood pressure in Chinese school-aged children during the COVID-19 quarantine. The cohort study of 445 school-aged children examined the change of BMI and blood pressure during the five-month quarantine. Multivariable Cox regression models were created to identify potential predictors of overweight, obesity, and elevated blood pressure (EBP). During the COVID-19 quarantine, the proportion of boys with overweight and obesity increased (P = 0.036), and the proportion of both boys and girls with Pre-EBP and EBP increased (P = 0.004 in boys; P < 0.001 in girls). The multivariate Cox regression analysis demonstrated that the setting, eating chili, parents' perception of their child's size and family doting were associated with overweight, obesity, and EBP. The study showed that BMI was more likely to increase in boys, and blood pressure increased in both boys and girls during the COVID-19 quarantine.

Integrative Analysis of the Metabolome and Transcriptome of a Cultivated Pepper and Its Wild Progenitor Chiltepin (Capsicum annuum L. var. glabriusculum) Revealed the Loss of Pungency During Capsicum Domestication

Pungency is a unique characteristic of chili peppers (Capsicum spp.) caused by capsaicinoids. The evolutionary emergence of pungency is thought to be a derived trait within the genus Capsicum. However, it is not well-known how pungency has varied during Capsicum domestication and specialization. In this study, we applied a comparative metabolomics along with transcriptomics analysis to assess various changes between two peppers (a mildly pungent cultivated pepper BB3 and its hot progenitor chiltepin) at four stages of fruit development, focusing on pungency variation. A total of 558 metabolites were detected in two peppers. In comparison with chiltepin, capsaicinoid accumulation in BB3 was almost negligible at the early stage. Next, 412 DEGs associated with the capsaicinoid accumulation pathway were identified through coexpression analysis, of which 18 genes (14 TFs, 3 CBGs, and 1 UGT) were deemed key regulators due to their high coefficients. Based on these data, we speculated that downregulation of these hub genes during the early fruit developmental stage leads to a loss in pungency during Capsicum domestication (from chiltepin to BB3). Of note, a putative UDP-glycosyltransferase, GT86A1, is thought to affect the stabilization of capsaicinoids. Our results lay the foundation for further research on the genetic diversity of pungency traits during Capsicum domestication and specialization.

Comprehensive Study of Scientific Evidence and Potential Risk of Herbal Medicine Use for Body Weight Reduction in North West Saudi Arabia

Herbal and home remedies are widely used worldwide especially those for weight loss. The prevalence of overweight and obesity in Saudi Arabia has highly elevated during the past decades. People in Saudi Arabia preferred the usage of remedies more than standard medicine. Therefore, we conducted this study to assess the use of weight reduction herbal and home remedies in Tabuk, North West Saudi Arabia. Data about weight-loss herbal remedies were collected from major local herbalist shops. In addition, inherited weight-loss herbal and household remedies were collected. Data collected included composition, method of preparation, method of use, and any reported side effects. Some of these remedies were used either alone or in combination. Majority of these ingredients were boiled in water to be drunk or directly added to food. Most of these mixtures were taken before food to reduce appetite. Most of these herbs were recorded to produce side effects. Mainly people suffer from gastric symptoms and headache. Many natural herbal and home remedies are still in use in Tabuk for weight reduction. Many of these remedies lack important scientific evidence for their usage, effectiveness, or safety.

A Critical Review on the Role of Food and Nutrition in the Energy Balance

The mass media has increasingly frequently suggested to the general population that specific foods or nutritional schemes are able to affect both human metabolism and energy expenditure, thus facilitating weight loss. This critical review is aimed at assessing available evidence on the roles of nutrients, food and dietary regimens in energy intake and energy expenditure. We queried the National Library of Medicine, the Cochrane Library, Excerpta Medica dataBASEand the Cumulative Index to Nursing and Allied Health Literature database, and a search strategy was performed by using database-specific subject headings and keywords. We found that available scientific evidence on these topics is scarce, and that the limited number of available studies often have poor methodological quality. Only a few foods show beneficial effects on metabolism and energy expenditure, as the human energy balance is complex and multifactorial. Finally, microbiota may interfere with the intake, use and expenditure of energy in the human body. Conclusive evidence is still lacking, and, at present, it is not possible to identify a food or a diet with a significant impact on human energy expenditure.

Fruits

Fruits come in a wide variety of colors, shapes, and flavors. This chapter will cover selected fruits that are known to be healthy and highly nutritious. These fruits were chosen due to their common usage and availability. Since it is not possible to cover all health benefits or essential nutrients and important phytochemicals of the fruit composition, this chapter will focus on the key valuable constituents and their potential health effects.

Biological Effects of Red Chili Pepper (<i>Capsicum annuum</i>) Consumption on High Fat Diet Female Albino Rats

BACKGROUND AND OBJECTIVE

The evidence for safe consumption of chili pepper to gain health benefits is insufficient as high doses reported to cause gastric erosion. The objective of this study was to investigate the contribution of red chili pepper ethanol extract (RCEE) to weight loss in high fat dieted female albino Wistar rats while monitoring adverse effects of high dose consumption.

MATERIALS AND METHODS

Body weight gain, lipid profile, oxidative stress parameters, liver, kidney and thyroid biochemical functions were determined in addition to histopathological examination of liver and kidney to determine biological effects of 2 ingested concentrations of red chili pepper extract (5 and 10 mg).

RESULTS

Red chili pepper ethanol extract (RCEE) showed anti-obesity potentials and hypolipidemic effects through decreased levels of total cholesterol (T.Ch), low density lipoprotein (LDL), triglycerides (TG) and very low density lipoprotein (VLDL) reached 25, 55, 45 and 45%, respectively, in parallel with increased high density lipoprotein (HDL) levels by 22.6%. The antioxidative potentials of RCEE were pronounced through significant increases in glutathione peroxidase (GPx) and catalase (CAT) activities (346.43 mU mL-1 and 15.33 U L-1 in group 2, respectively). Histological examination of liver and kidney showed adverse results but that did not significantly reflect on their functional biochemical parameters.

CONCLUSION

Results introduced scientific evidence that red chili pepper possesses functional pharmacological properties but the excessive consumption induces liver and kidney damage.

Association of the frequency of spicy food intake and the risk of abdominal obesity in rural Chinese adults: a cross-sectional study

OBJECTIVES

Recent data relating to the association between spicy food intake frequency and abdominal obesity are limited, especially in low-income areas. Therefore, the study explored the relationship between spicy food intake frequency and abdominal obesity, and assessed the role of energy intake as a mediator of these associations in a rural Chinese adult population.

DESIGN

Cross-sectional study.

SETTING

Rural Chinese adult population.

PARTICIPANTS

Subjects from Henan Rural Cohort Study (n=28 773).

PRIMARY OUTCOME MEASURES

The effects of spicy food intake frequency on abdominal obesity were analysed by restricted cubic spline and logistic regression, and the mediation effect was analysed using the bootstrap method.

RESULTS

The adjusted percentages of abdominal obesity were 47.32%, 51.93%, 50.66% and 50.29% in the spicy food intake subgroups of never, 1-2 day/week, 3-5 day/week and 6-7 day/week, respectively. An inverse U-shaped association was found between spicy food intake frequency and abdominal obesity (p<0.01). Compared with subjects who never consumed spicy food, the adjusted ORs (95% CIs) in the 1-2 day/week, 3-5 day/week and 6-7 day/week subgroups were 1.186 (1.093, 1.287), 1.127 (1.038, 1.224) and 1.104 (1.044, 1.169), respectively. Furthermore, the increased odd of abdominal obesity related to more frequent spicy food intake was mediated by higher fat energy intake; the direct and indirect effects were 1.107 (1.053, 1.164) and 1.007 (1.003, 1.012), respectively.

CONCLUSIONS

The data indicated that spicy food intake increased the risk of abdominal obesity, and fat energy intake may be a mediator of this association in rural Chinese populations. Clarifying the mechanisms will facilitate the development of novel preventive and therapeutic approaches for abdominal obesity.

TRIAL REGISTRATION NUMBER

ChiCTR-OOC-15006699.

Placenta, Pericarp, and Seeds of Tabasco Chili Pepper Fruits Show a Contrasting Diversity of Bioactive Metabolites

Chili pepper (Capsicum spp.) is one of the most important horticultural crops worldwide, and its unique organoleptic properties and health benefits have been established for centuries. However, there is little knowledge about how metabolites are distributed throughout fruit parts. This work focuses on the use of liquid chromatography coupled with high resolution mass spectrometry (UHPLC-ESI-HRMS) to estimate the global metabolite profiles of the pericarp, placenta, and seeds of Tabasco pepper fruits (Capsicum frutescens L.) at the red mature stage of ripening. Our main results putatively identified 60 differential compounds between these tissues and seeds. Firstly, we found that pericarp has a higher content of glycosides, showing on average a fold change of 5 and a fold change of 14 for terpenoids when compared with other parts of the fruit. While placenta was the richest tissue in capsaicinoid-related compounds, alkaloids, and tocopherols, with a 35, 3, and 7 fold change, respectively. However, the seeds were richer in fatty acids and saponins with fold changes of 86 and 224, respectively. Therefore, our study demonstrates that a non-targeted metabolomic approach may help to improve our understanding of unexplored areas of plant metabolism and also may be the starting point for a detailed analysis in complex plant parts, such as fruits.

TRPV1 Antagonists as Novel Anti-Diabetic Agents: Regulation of Oral Glucose Tolerance and Insulin Secretion Through Reduction of Low-Grade Inflammation?

With a global prevalence among adults over 18 years of age approaching 9%, Type 2 diabetes mellitus (T2DM) has reached pandemic proportions and represents a major unmet medical need. To date, no disease modifying treatment is available for T2DM patients. Accumulating evidence suggest that the sensory nervous system is involved in the progression of T2DM by maintaining low-grade inflammation via the vanilloid (capsaicin) receptor, Transient Receptor Potential Vanilloid-1 (TRPV1). In this study, we tested the hypothesis that TRPV1 is directly involved in glucose homeostasis in rodents. TRPV1 receptor knockout mice (Trpv1^−/−) and their wild-type littermates were kept on high-fat diet for 15 weeks. Moreover, Zucker obese rats were given the small molecule TRPV1 antagonist, N-(4-Tertiarybutylphenyl)-4-(3-cholorphyridin-2-yl)tetrahydropyrazine-1(2H)-carbox-amide (BCTC), per os twice-a-day or vehicle for eight days. Oral glucose tolerance and glucose-stimulated insulin secretion was improved by both genetic inactivation (Trpv1^−/− mice) and pharmacological blockade (BCTC) of TRPV1. In the obese rat, the improved glucose tolerance was accompanied by a reduction in inflammatory markers in the mesenteric fat, suggesting that blockade of low-grade inflammation contributes to the positive effect of TRPV1 antagonism on glucose metabolism. We propose that TRPV1 could be a promising therapeutic target in T2DM by improving glucose intolerance and correcting dysfunctional insulin secretion.

Calcium Signaling Pathways: Key Pathways in the Regulation of Obesity

Nowadays, high epidemic obesity-triggered hypertension and diabetes seriously damage social public health. There is now a general consensus that the body's fat content exceeding a certain threshold can lead to obesity. Calcium ion is one of the most abundant ions in the human body. A large number of studies have shown that calcium signaling could play a major role in increasing energy consumption by enhancing the metabolism and the differentiation of adipocytes and reducing food intake through regulating neuronal excitability, thereby effectively decreasing the occurrence of obesity. In this paper, we review multiple calcium signaling pathways, including the IP3 (inositol 1,4,5-trisphosphate)-Ca²⁺ (calcium ion) pathway, the p38-MAPK (mitogen-activated protein kinase) pathway, and the calmodulin binding pathway, which are involved in biological clock, intestinal microbial activity, and nerve excitability to regulate food intake, metabolism, and differentiation of adipocytes in mammals, resulting in the improvement of obesity.

Capsaicin Analogues Derived from n-3 Polyunsaturated Fatty Acids (PUFAs) Reduce Inflammatory Activity of Macrophages and Stimulate Insulin Secretion by β-Cells In Vitro

In this study, two capsaicin analogues, N-eicosapentaenoyl vanillylamine (EPVA) and N-docosahexaenoyl vanillylamine (DHVA), were enzymatically synthesized from their corresponding n-3 long chain polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), both dietary relevant components. The compounds significantly reduced the production of some lipopolysaccharide (LPS)-induced inflammatory mediators, including nitric oxide (NO), macrophage-inflammatory protein-3α (CCL20) and monocyte chemoattractant protein-1 (MCP-1 or CCL2), by RAW264.7 macrophages. Next to this, only EPVA increased insulin secretion by pancreatic INS-1 832/13 β-cells, while raising intracellular Ca2+ and ATP concentrations. This suggests that the stimulation of insulin release occurs through an increase in the intracellular ATP/ADP ratio in the first phase, while is calcium-mediated in the second phase. Although it is not yet known whether EPVA is endogenously produced, its potential therapeutic value for diabetes treatment merits further investigation.

Capsaicinoids: Pungency beyond Capsicum

Capsaicinoids are metabolites responsible for the appealing pungency of Capsicum (chili pepper) species. The completion of the Capsicum annuum genome has sparked new interest into the development of biotechnological applications involving the manipulation of pungency levels. Pungent dishes are already part of the traditional cuisine in many countries, and numerous health benefits and industrial applications are associated to capsaicinoids. This raises the question of how to successfully produce more capsaicinoids, whose biosynthesis is strongly influenced by genotype-environment interactions in fruits of Capsicum. In this Opinion article we propose that activating the capsaicinoid biosynthetic pathway in a more amenable species such as tomato could be the next step in the fascinating story of pungent crops.

Potential Phytopharmacy and Food Applications of Capsicum spp.: A Comprehensive Review

Capsicum genus (Solanaceae) is native to the Americas. Today, it is an important agricultural crop cultivated around the world, not only due to its economic importance, but also for the nutritional value of the fruits. Among their phytochemical constituents, capsaicinoids are characteristic and responsible of the pungency of sharp-tasting cultivars. Moreover, Capsicum and capsaicinoids (mainly, capsaicin) have been largely studied because of their health benefits. Thus, this study reviews the scientific knowledge about Capsicum spp. and their phytochemicals against cancer, diabetes, gastrointestinal diseases, pain, and metabolic syndrome, as well as their antioxidant and antimicrobial activity. These bioactivities can be the basis of the formulation of functional ingredients and natural preservatives containing Capsicum extracts or isolated compounds.

Black pepper-based beverage induced appetite-suppressing effects without altering postprandial glycaemia, gut and thyroid hormones or gastrointestinal well-being: a randomized crossover study in healthy subjects

Pleiotropic effects of spices on health, particularly on glucose metabolism and energy regulation, deserve further clinical investigation into their efficacy.

Diversity effect of capsaicin on different types of skeletal muscle

Capsaicin is a major pungent content in green and red peppers which are widely used as spice, and capsaicin may activate different receptors. To determine whether capsaicin has different effects on different types of skeletal muscle, we applied different concentrations (0, 0.01, and 0.02%) of capsaicin in the normal diet and conducted a four-week experiment on Sprague-Dawley rats. The fiber type composition, glucose metabolism enzyme activity, and different signaling molecules' expressions of receptors were detected. Our results suggested that capsaicin reduced the body fat deposition, while promoting the slow muscle-related gene expression and increasing the enzyme activity in the gastrocnemius and soleus muscles. However, fatty acid metabolism was significantly increased only in the soleus muscle. The study of intracellular signaling suggested that the transient receptor potential vanilloid 1 (TRPV1) and cannabinoid receptors in the soleus muscle were more sensitive to capsaicin. In conclusion, the distribution of TRPV1 and cannabinoid receptors differs in different types of muscle, and the different roles of capsaicin in different types of muscle may be related to the different degrees of activation of receptors.