Sesame Extract Promotes Chemopreventive Effect of Hesperidin on Early Phase of Diethylnitrosamine-Initiated Hepatocarcinogenesis in Rats

The combination of natural products is an alternative approach to achieving chemopreventive potential. Accordingly, citrus hesperidin exhibits numerous biological activities, including anticarcinogenic activities, while the sesamin in sesame exhibits potent anticancer activities and lipid-lowering effects. We investigated the cancer chemopreventive effects of mixed sesame and orange seed extract (MSO) containing hesperidin and sesamin in diethylnitrosamine (DEN)-induced hepatocarcinogenesis. Rats were injected with DEN once a week for 3 weeks to induce hepatocarcinogenesis. Rats were fed with MSO and various compositions that included sesame extract (SE) and hesperidin. The 10-week administration of MSO more effectively inhibited the number and size of hepatic GST-P-positive foci than hesperidin in DEN-initiated rats. MSO and hesperidin decreased the number of PCNA-positive hepatocytes but increased the apoptotic cells in DEN-induced rats. Furthermore, MSO and its constituents suppressed hepatic triglyceride content concurrently along with the expression of fatty acid synthase. Although the 5-week administration of MSO or hesperidin did not alter hepatic, preneoplastic lesion formation in DEN-initiated rats, it alleviated DEN-induced hepatotoxicity. MSO and its applied compositions did not impact upon the cytochrome P450 system. In conclusion, sesame extract promoted the chemopreventive effect of hesperidin on DEN-induced early stage of hepatocarcinogenesis in rats. The inhibitory mechanisms are likely involved with the induction of cell apoptosis, suppression of cell proliferation and modulation of hepatic lipogenesis. This study may provide revelations in the development of alternative treatments against hepatocellular carcinoma.

Protective Effects of Sesamin on Cytoxan-Induced Spermatogenesis Dysfunction by Regulating RNF8-ubH2A/ubH2B Pathways in Male Mice

Most of the clinically infertile patients show spermatogenesis dysfunction. Cyclophosphamide, as an anticancer drug, can induce spermatogenesis dysfunction. Sesamin is the main bioactive component of natural lignans in sesame. It is abundant in sesame oil and has strong biological activities such as antioxidant, antibacterial, and hypoglycemic properties. By establishing the model of spermatogenic dysfunction induced by cyclophosphamide in male mice and then feeding sesamin (50, 100, and 200 mg/kg) for 2 weeks, we proved that sesamin can improve the reproductive organ damage induced by cyclophosphamide and increase the number and activity of sperms. Sesamin can resist cyclophosphamide-induced sperm nuclear maturity and DNA damage by increasing the expression levels of histones H2A and H2B in the testis. In addition, sesamin can improve the ubiquitination of histones regulated by RNF8 to protect the testis. In conclusion, these results suggest that sesamin can improve spermatogenic dysfunction induced by cyclophosphamide, which may be mediated by ubiquitination of histones.

Sesamin exerts anti-tumor activity in esophageal squamous cell carcinoma via inhibition of TRIM44 and NF-κB signaling

Tripartite motif-containing 44 (TRIM44) is known to play an oncogenic role in multiple human cancers, including esophageal cancer. Sesamin possesses potent anti-inflammatory and anti-cancer properties for various cancers. This study is designed to unravel the biological functions of sesamin and TRIM44 in esophageal cancer. TRIM44 expression in esophageal squamous cell cancer (ESCC) cell lines and tissues was determined by RT-qPCR assay and Western blot. The effects of sesamin and TRIM44 on ESCC cell growth in vivo and in vitro were assessed by the mouse model and CCK-8 assay, respectively. We found that TRIM44 was significantly upregulated in ESCC cell lines and tissues when compared to their counterparts. Sesamin treatment or depletion of TRIM44 markedly reduced ESCC cell proliferation. The nuclear factor kappa B (NF-κB) and toll-like receptor 4 (TLR4) signaling pathway may be involved in sesamin-mediated TRIM44 suppression. Finally, we showed that oral administration of sesamin dramatically inhibited tumor growth or ESCC in nude mice. Our results suggest that sesamin exerts anti-tumor activity in ESCC via inhibition of NF-κB signaling pathway, demonstrating its potential for the treatment of esophageal cancer.

Sesamin Activates Nrf2/Cnc-Dependent Transcription in the Absence of Oxidative Stress in Drosophila Adult Brains

Sesamin, a major lignin in sesame seeds, possesses health-promoting properties. Sesamin feeding suppresses several aging-related phenotypes such as age-dependent accumulation of damaged proteins in the muscles and neuronal loss in the brains of Drosophila adults with high levels of reactive oxygen species. Sesamin promotes the transcription of several genes that are responsible for oxidative stress, although the underlying mechanism remains unclear. Here, we aimed to demonstrate that sesamin mediates its action through activation of a transcription factor, Nrf2 (Cnc in Drosophila), essential for anti-aging oxidative stress response. Nrf2/Cnc activation was determined using the antioxidant response element, Green Fluorescence Protein reporter, that can monitor Nrf2/Cnc-dependent transcription. We observed strong fluorescence in the entire bodies, particularly in the abdomens and brains, of adult flies fed sesamin. Interestingly, Nrf2/Cnc was strongly activated in neuronal cells, especially in several neuron types, including glutamatergic and cholinergic, and some dopaminergic and/or serotonergic neurons but not in GABAergic neurons or the mushroom bodies of flies fed sesamin. These results indicate that the anti-aging effects of sesamin are exerted via activation of Nrf2/Cnc-dependent transcription to circumvent oxidative stress accumulation in several types of neurons of adult brains. Sesamin could be explored as a potential dietary supplement for preventing neurodegeneration associated with accumulation of oxidative stress.

A comprehensive mechanistic insight into the dietary and estrogenic lignans, arctigenin and sesamin as potential anticarcinogenic and anticancer agents. Current status, challenges, and future perspectives

A large body of evidence indicates that lignans as polyphenolic compounds are beneficial against life-threatening diseases such as cancer. Plant lignans have the potential to induce cancer cell death and interfere with carcinogenesis, tumor growth, and metastasis. Epidemiological studies have revealed that the intake of lignans is inversely associated with the risk of several cancers. Moreover, numerous experimental studies demonstrate that natural lignans significantly suppress cancer cell proliferation with minimal toxicity against non-transformed cells. Dietary lignans arctigenin and sesamin have been found to have potent antiproliferative activities against various types of human cancer. The purpose of this review is to provide the reader with a deeper understanding of the cellular and molecular mechanisms underlying anticancer effects of arctigenin and sesamin. Our review comprehensively describes the effects of arctigenin and sesamin on the signaling pathways and related molecules involved in cancer cell proliferation and invasion. The findings of present review show that the dietary lignans arctigenin and sesamin seem to be promising carcinopreventive and anticancer agents. These natural lignans can be used as dietary supplements and pharmaceuticals for prevention and treatment of cancer.

Lignans of Sesame (Sesamum indicum L.): A Comprehensive Review

Major lignans of sesame sesamin and sesamolin are benzodioxol--substituted furofurans. Sesamol, sesaminol, its epimers, and episesamin are transformation products found in processed products. Synthetic routes to all lignans are known but only sesamol is synthesized industrially. Biosynthesis of furofuran lignans begins with the dimerization of coniferyl alcohol, followed by the formation of dioxoles, oxidation, and glycosylation. Most genes of the lignan pathway in sesame have been identified but the inheritance of lignan content is poorly understood. Health-promoting properties make lignans attractive components of functional food. Lignans enhance the efficiency of insecticides and possess antifeedant activity, but their biological function in plants remains hypothetical. In this work, extensive literature including historical texts is reviewed, controversial issues are critically examined, and errors perpetuated in literature are corrected. The following aspects are covered: chemical properties and transformations of lignans; analysis, purification, and total synthesis; occurrence in Seseamum indicum and related plants; biosynthesis and genetics; biological activities; health-promoting properties; and biological functions. Finally, the improvement of lignan content in sesame seeds by breeding and biotechnology and the potential of hairy roots for manufacturing lignans in vitro are outlined.

In Vitro Inhibitory Effects of Sesamin on CYP4F2 Activity

Sesamin is a major lignan in sesame seeds, and a recent meta-analysis of controlled trials indicated that sesamin intake decreases blood pressure. The antihypertensive effect of sesamin has been suggested to be due to sesamin-mediated suppression of 20-hydroxyeicosatetraenoic acid production catalyzed by CYP4F2. However, the detailed mechanism underlying inhibition of CYP4F2 function by sesamin remains unclear. In this study, the effects of sesamin on catalytic activity of CYP4F2 were investigated in vitro. Sesamin inhibited luciferin-4F2/3 O-dealkylase activity of recombinant human CYP4F2 with an IC₅₀ value of 0.381 µM. When preincubated in the presence of reduced nicotinamide adenine dinucleotide phosphate (NADPH) for 20 min, sesamin potentiated the inhibition of CYP4F2 activity. Moreover, kinetic analysis of the inactivation revealed that sesamin showed a preincubation time- and concentration-dependent inhibition of CYP4F2 activity yielding a maximal inactivation rate constant (k_inact) value of 0.354 min^-1 and half-maximal inhibitory concentration (K_I) value of 1.12 µM. The inactivation of CYP4F2 by sesamin required NADPH. These results indicated that sesamin is a mechanism-based inactivator of human CYP4F2.

Autophagy and apoptosis induction by sesamin in MOLT-4 and NB4 leukemia cells

Sesamin, the major furofuran lignan found in the seeds of Sesamum indicum L., has been investigated for its various medicinal properties. In the present study, the anti-leukemic effects of sesamin and its underlying mechanisms were investigated in MOLT-4 and NB4 acute leukemic cells. Leukemic cells were treated with various concentrations of sesamin. Cell viability was determined using an MTT assay. Flow cytometry using Annexin V-FITC/PI staining and anti-LC3/FITC antibodies was applied to detect the level of apoptosis and autophagy, respectively. Reverse transcription-quantitative PCR was performed to examine the alterations in the mRNA expression of apoptotic and autophagic genes. In addition, bioinformatics tools were used to predict the possible interactions between sesamin and its targets. The results revealed that sesamin inhibited MOLT-4 and NB4 cell proliferation in a dose-dependent manner. In addition, sesamin induced both apoptosis and autophagy. In sesamin-treated cells, the gene expression levels of caspase 3 and unc-51 like autophagy activating kinase 1 (ULK1) were upregulated, while those of mTOR were downregulated compared with in the control. Notably, the protein-chemical interaction network indicated that caspase 3, mTOR and ULK1 were the essential factors involved in the effects of sesamin treatment, as with anticancer agents, such as rapamycin, AZD8055, Torin1 and 2. Overall, the findings of the present study suggested that sesamin inhibited MOLT-4 and NB4 cell proliferation, and induced apoptosis and autophagy through the regulation of caspase 3 and mTOR/ULK1 signaling, respectively.

Simultaneous and rapid determination of sesamin and sesamolin in sesame oils using excitation-emission matrix fluorescence coupled with self-weighted alternating trilinear decomposition

BACKGROUND

Sesamin and sesamolin are two typical and important lignans isolated from sesame oil. Various studies have shown the bioactivity, physiological activity, and potential health benefits of the two components. In this study, a rapid method for the simultaneous determination of sesamin and sesamolin in sesame oils was proposed. The excitation-emission fluorescence spectra of the oils were obtained after a simple pretreatment, then self-weighted alternating trilinear decomposition was used to extract the quantitative information from the very overlapping spectra.

RESULTS

It was found that reasonable quantification results could be obtained with the limits of detection for the two lignans. These limits were 0.05 mg/g and 0.24 mg/g, and the limits of quantitation were 0.14 mg/g and 0.74 mg/g, respectively. The average recoveries for sesamin and sesamolin were 99.05% and 94.97%.

CONCLUSION

The results indicate that, with simple sample pretreatment, the application for combining excitation-emission fluorescence spectra and self-weighted alternating trilinear decomposition can be a useful and sensitive tool for the determination of lignans in sesame oil. © 2020 Society of Chemical Industry.

Self-Nanoemulsifying Drug Delivery Systems for Enhancing Solubility, Permeability, and Bioavailability of Sesamin

Sesamin (SSM) is a water-insoluble compound that is easily eliminated by liver metabolism. To improve the solubility and bioavailability of SSM, this study developed and characterized a self-nanoemulsifying drug delivery system (SNEDDS) for the oral delivery of SSM and conducted pharmacokinetic assessments. Oil and surfactant materials suitable for SNEDDS preparation were selected on the basis of their saturation solubility at 37 ± 0.5 °C. The mixing ratios of excipients were determined on the basis of their dispersibility, transmittance (%), droplet sizes, and polydispersity index. An SNEDDS (F10) formulation comprising glyceryl trioctanoate, polyoxyethylene castor oil, and Tween 20 at a ratio of 10:10:80 (w/w/w) was the optimal formulation. This formulation maintained over 90% of its contents in different storage environments for 12 weeks. After the self-emulsification of SNEDDS, the SSM dispersed droplet size was 66.4 ± 31.4 nm, intestinal permeability increased by more than three-fold, relative bioavailability increased by approximately 12.9-fold, and absolute bioavailability increased from 0.3% to 4.4%. Accordingly, the developed SNEDDS formulation can preserve SSM's solubility, permeability, and bioavailability. Therefore, this SNEDDS formulation has great potential for the oral administration of SSM, which can enhance its pharmacological application value.

Effects of Sesamin, the Major Furofuran Lignan of Sesame Oil, on the Amplitude and Gating of Voltage-Gated Na+ and K+ Currents

Sesamin (SSM) and sesamolin (SesA) are the two major furofuran lignans of sesame oil and they have been previously noticed to exert various biological actions. However, their modulatory actions on different types of ionic currents in electrically excitable cells remain largely unresolved. The present experiments were undertaken to explore the possible perturbations of SSM and SesA on different types of ionic currents, e.g., voltage-gated Na⁺ currents (I_Na), erg-mediated K⁺ currents (I_K(erg)), M-type K⁺ currents (I_K(M)), delayed-rectifier K⁺ currents (I_K(DR)) and hyperpolarization-activated cation currents (I_h) identified from pituitary tumor (GH₃) cells. The exposure to SSM or SesA depressed the transient and late components of I_Na with different potencies. The IC₅₀ value of SSM needed to lessen the peak or sustained I_Na was calculated to be 7.2 or 0.6 μM, while that of SesA was 9.8 or 2.5 μM, respectively. The dissociation constant of SSM-perturbed inhibition on I_Na, based on the first-order reaction scheme, was measured to be 0.93 μM, a value very similar to the IC₅₀ for its depressant action on sustained I_Na. The addition of SSM was also effective at suppressing the amplitude of resurgent I_Na. The addition of SSM could concentration-dependently inhibit the I_K(M) amplitude with an IC₅₀ value of 4.8 μM. SSM at a concentration of 30 μM could suppress the amplitude of I_K(erg), while at 10 μM, it mildly decreased the I_K(DR) amplitude. However, the addition of neither SSM (10 μM) nor SesA (10 μM) altered the amplitude or kinetics of I_h in response to long-lasting hyperpolarization. Additionally, in this study, a modified Markovian model designed for SCN8A-encoded (or Na_V1.6) channels was implemented to evaluate the plausible modifications of SSM on the gating kinetics of Na_V channels. The model demonstrated herein was well suited to predict that the SSM-mediated decrease in peak I_Na, followed by increased current inactivation, which could largely account for its favorable decrease in the probability of the open-blocked over open state of Na_V channels. Collectively, our study provides evidence that highlights the notion that SSM or SesA could block multiple ion currents, such as I_Na and I_K(M), and suggests that these actions are potentially important and may participate in the functional activities of various electrically excitable cells in vivo.

Antimetastatic Effects of Sesamin on Human Head and Neck Squamous Cell Carcinoma through Regulation of Matrix Metalloproteinase-2

Background: Sesamin is a lignin present in sesame oil from the bark of Zanthoxylum spp. Sesamin reportedly has anticarcinogenic potential and exerts anti-inflammatory effects on several tumors. Hypothesis/Purpose: However, the effect of sesamin on metastatic progression in human head and neck squamous carcinoma (HNSCC) remains unknown in vitro and in vivo; hence, we investigated the effect of sesamin on HNSCC cells in vitro. Methods and Results: Sesamin-treated human oral cancer cell lines FaDu, HSC-3, and Ca9-22 were subjected to a wound-healing assay. Furthermore, Western blotting was performed to assess the effect of sesamin on the expression levels of matrix metalloproteinase (MMP)-2 and proteins of the MAPK signaling pathway, including p-ERK1/2, P-p38, and p-JNK1/2. In addition, we investigated the association between MMP-2 expression and the MAPK pathway in sesamin-treated oral cancer cells. Sesamin inhibited cell migration and invasion in FaDu, Ca9-22, and HSC-3 cells and suppressed MMP-2 at noncytotoxic concentrations (0 to 40 μM). Furthermore, sesamin significantly reduced p38 MAPK and JNK phosphorylation in a dose-dependent manner in FaDu and HSC-3 cells. Conclusions: These results indicate that sesamin suppresses the migration and invasion of HNSCC cells by regulating MMP-2 and is thus a potential antimetastatic agent for treating HNSCC.

Determination and Daily Intake Estimation of Lignans in Sesame Seeds and Sesame Oil Products in Korea

Sesame (Sesamum indicum L.) is a plant that belongs to the Pedaliaceae family which was first classified as a food source around 4000 years ago. Lignans (sesamin, sesamolin, sesamol, and sesaminol) present in sesame are the primary functional compounds that impart important health benefits. However, very little information is available on the lignan intake from sesame seeds and sesame oil products. Sesame oil is frequently and highly consumed in Korea and therefore is one of the important lignan intake sources due to the food eating habits of Koreans. Herein, we studied the distribution of lignans in sesame seeds (n = 21) and oil (n = 34) to estimate the daily lignan intake by the Korean population. High-performance liquid chromatography, in conjunction with statistical analysis, was used to determine the lignan content of seeds and oil. The estimated daily intake of total lignans from sesame seeds and oil, as estimated from the available domestic consumption data (Korea Nutrition and Health Examination Survey), is 18.39 mg/person/day for males and 13.26 mg/person/day for females. The contributions of lignan intake from sesame seeds and oil are 23.0% and 77.0%, respectively. This study provides preliminary information on lignan intake from sesame seeds and oil in the Korean population.

Sesamin Induces Endothelial Nitric Oxide Synthase Activation via Transient Receptor Potential Vanilloid Type 1

Sesamin, the most abundant lignan in sesame seed oil, has many biological activities. However, the underlying molecular mechanisms behind the regulatory effects of sesamin on endothelial nitric oxide synthase (eNOS) activity and nitric oxide (NO) generation in endothelial cells (ECs) remain unclear. Sesamin induced the intracellular level of NO and eNOS phosphorylation in ECs in a concentration- and time-dependent manner. Additionally, sesamin induced levels of intracellular calcium, leading to the phosphorylation of calmodulin-dependent protein kinase II (CaMKII) at Thr286, calcium/calmodulin-dependent protein kinase kinase beta (CaMKKβ) at Ser511, protein kinase A (PKA) at Thr197, Akt at Ser473, and AMP-activated protein kinase (AMPK) at Thr172. In particular, blocking of the transient receptor potential vanilloid type 1 (TRPV1) channel by capsazepine (TRPV1 antagonist), as well as TRPV1 knockdown via TRPV1 silencing RNA, abrogated sesamin-induced PKA, Akt, AMPK, CaMKII, CaMKKβ, and eNOS phosphorylation and NO level in ECs. Furthermore, sesamin inhibited TNF-α-induced NF-κB translocation, intercellular adhesion molecule-1 expression, and monocyte adhesion. Sesamin triggered eNOS activity and NO production via activation of TRPV1-calcium signaling, which involved the phosphorylation of PKA, CaMKII, CaMKKβ, Akt, and AMPK. Sesamin may be useful for treating or preventing the endothelial dysfunction correlated with cardiovascular diseases.

Sesamum indicum L. Oil and Sesamin Induce Auditory-Protective Effects Through Changes in Hearing Loss-Related Gene Expression

Changing consumption patterns and increasing health awareness, especially in Europe, are resulting in an increased demand for sesame seeds. In 2016, Asia imported the highest quantity of sesame seeds, followed by Europe and North America. We examined, for the first time, the effects of treatment with sesame oil and sesamin in hearing impairment models. Sesame oil exhibited an ameliorative effect on auditory impairment in a hair cell line in zebrafish and mice. In ototoxic zebrafish larvae, neuromasts and otic cells increased in numbers because of sesame oil. Furthermore, auditory function in noise-induced hearing loss (NIHL) was studied through auditory brainstem response to evaluate the therapeutic effects of sesame oil. Sesame oil reduced the hearing threshold shift in response to clicks and 8, 16-kHz tone bursts in NIHL mice. Auditory-protective effect of sesame oil was seen in zebrafish and mice; therefore, we used chromatographic analysis to study sesamin, which is the major effective factor in sesame oil. To investigate its effects related to auditory function, we studied the hearing-related gene, Tecta, using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazoliumbromide (MTT) assay. Auditory cell proliferation was induced by treatment with sesame oil and sesamin using Tecta (Tectorin Alpha) regulation. The expression of Tecta increases in the apex area of the cochlear hair cells as they grow, and their activity is enhanced by sesame oil and sesamin. These results provide a novel mechanistic insight into the sesame oil activities and suggest that sesamin, the key constituent in sesame oil, is responsible for its auditory function related benefits, including protection of auditory cells and reversal of their impairments.

Supplementation of Sesamin Alleviates Stress-Induced Behavioral and Psychological Disorders via Reshaping the Gut Microbiota Structure

Sesamin, a lignan from sesame seed, has been reported to attenuate chronic mild stress-induced depressive-like behaviors. Gut microbiota play pivotal roles in mediating psychological behaviors by regulating gut barrier integrity and systemic inflammatory responses. Here, we found that oral sesamin administration (50 mg/kg·bodyweight/day) significantly attenuated depressive, aversive, repetitive, and anxiety-like behaviors in a long-term multiple nonsocial stress-treated mice model. Sesamin inhibited stress-induced gut barrier integrity damage, reduced circulating lipopolysaccharide (LPS) levels, and suppressed neuroinflammatory responses. Moreover, sesamin treatment also restructured the gut microbiome by enhancing the relative abundances of Bacteroidales and S24-7. The correlation analysis indicated that the microbiota composition changes were strongly correlated with behavioral disorders, serotonin, norepinephrine, and LPS levels. In conclusion, sesamin has preventive effects on stress-induced behavioral and psychological disorders, which might be highly related to the reshaped microbiota composition. This study provides a clue for understanding the systemic mechanism of anti-depression effects of sesamin.

Sesamin ameliorates mucosal tissue injury of mesenteric ischemia and reperfusion in an experimental rat model

INTRODUCTION

Mesenteric ischemia/reperfusion (I/R) injury is a serious clinical condition. There were a lot of experimental studies performed in the treatment of I/R injury. To our knowledge, this is the first experimental study with effects of sesamin on I/R injury model. We aimed to investigate the protective effect of sesamin on mesenteric I/R injury model.

MATERIAL AND METHODS

A total of 32 male Sprague-Dawley rats were divided into four groups. Control group: superior mesenteric artery (SMA) exposed without clamping. I/R group: SMA was clamped for 60 min and then reperfused for 2 h. Sesamin group (S): 30 mg/kg sesamin were given for 5 days, and SMA exposed without clamping. I/R + S group: 30 mg/kg sesamin were given for 5 days, SMA was clamped for 60 min, and then reperfused for 2 h. Plasma and tissue oxidant parameters were investigated as well as histopathological evaluation.

RESULTS

Plasma and tissue total antioxidant status (TAS) levels were significantly higher in I/R + S group compared to the rest (p < 0.005). The plasma TAS levels in I/R group was significantly low. The highest tissue TAS levels were detected in I/R + S group. The high levels of plasma and tissue TOS were found in I/R + S group. Plasma and tissue OSI levels were significantly higher in I/R group. Histopathologic evaluation showed that the mean level of intestinal tissue injury score in I/R group was 2.75 and 1.38 in I/R + S group.

CONCLUSIONS

Sesamin helps to protect the intestinal tissue at the cellular level by reducing the oxidative stress and inflammation at both the plasma and tissue levels in the experimental I/R model.

Protective Effects of Sesamin against UVB-Induced Skin Inflammation and Photodamage In Vitro and In Vivo

Ultraviolet (UV) exposure has been demonstrated as the most critical factor causing extrinsic skin aging and inflammation. This study explored the protective effects and mechanisms of sesamin against skin photodamage. Sesamin reduced intracellular reactive oxygen species production after UVB irradiation in human dermal fibroblasts. The sesamin treatment attenuated mitogen-activated protein (MAP) kinase phosphorylation and matrix metalloproteinase (MMPs) overexpression induced by UVB exposure, and it significantly enhanced the tissue inhibitor of metalloproteinase-1 protein expression. Sesamin also elevated the total collagen content in human fibroblasts by inhibiting UVB-induced mothers against decapentaplegic homolog 7 (Smad7) protein expression. Sesamin reduced UVB-induced inducible nitric oxide synthase (i-NOS) and cyclooxygenase-2 (COX-2) overexpression and inhibited nuclear factor-kappa B (NF-κB) translocation. Moreover, sesamin may regulate the c-Jun N-terminal kinases (JNK) and p38 MAP kinase pathways, which inhibit COX-2 expression. Sesamin could reduce UVB-induced inflammation, epidermal hyperplasia, collagen degradation, and wrinkle formation in hairless mice. It also reduced MMP-1, interleukin (IL-1), i-NOS, and NF-κB in the mouse skin. These results demonstrate that sesamin had antiphotodamage and anti-inflammatory activities. Sesamin has potential for use as a skin protection agent in antiphotodamage and skin care products.

A randomized, triple-blind, placebo-controlled clinical trial, evaluating the sesamin supplement effects on proteolytic enzymes, inflammatory markers, and clinical indices in women with rheumatoid arthritis

Inflammation is one of the main characteristics of rheumatoid arthritis. Based on the antiinflammatory properties of sesame, this study was conducted to evaluate the sesamin supplement effects on serum levels of some proteolytic enzymes, inflammatory biomarkers, and clinical indices in women with rheumatoid arthritis. In this randomized, triple-blind, placebo-controlled clinical trial, 44 patients were randomly divided in intervention and control groups. Patients received 200-mg/day sesamin supplement or placebo in the intervention and control group for 6 weeks. Serum levels of proteolytic enzymes (hyaluronidase, aggrecanase, and matrix metalloproteinases-3) and inflammatory biomarkers (hs-CRP, IL-1β, IL-6, TNF-α, and cyclooxygenase-2) were measured with enzyme-linked immunosorbent assay method at the beginning and end of the study. After intervention, serum levels of hyaluronidase and matrix metalloproteinases-3 decreased significantly in sesamin group. Also, serum levels of hs-CRP, TNF-α, and cyclooxygenase-2 in intervention group were significantly decreased in intervention group compared with placebo group. Sesamin supplementation also caused a significant reduction in the number of tender joints and severity of pain in these patients. According to the results, it seems that the sesamin by reducing inflammatory mediators can relieve clinical symptoms and pathological changes that caused by inflammatory impairment in patients with rheumatoid arthritis.

Sesame Lignans Suppress Age-Related Cognitive Decline in Senescence-Accelerated Mice

Sesame lignans, which are biologically active compounds present in sesame seeds and oil, are known to have neuroprotective effects in several models of brain dysfunction. However, the effects of sesame lignans on age-related brain dysfunction are not clear and were thus investigated in the present study using a senescence-accelerated mouse (SAMP10). Two-month-old male SAMP10 mice were administrated a basal diet with 0% or 0.05% sesame lignans for two months, or with 0%, 0.02%, or 0.05% sesame lignans for 10 months and subjected to step-through passive avoidance tasks and forced swim tests. Reactive carbonyl species (RCs) were evaluated as markers of oxidative stress using a recently developed comprehensive analytical method. Both learning time in passive avoidance tasks and immobile time in forced swim tests became longer with aging (p < 0.05). However, the administration of sesame lignans significantly ameliorated age-related effects in both tests (p < 0.05). Age-related increases in RCs such as 4-hydroxy-2-nonenal in the cerebral cortex and liver were reduced in mice fed sesame lignans. These results suggest that sesame lignans can prevent age-related brain dysfunction via anti-oxidative activity.

Sesamin Catechol Glucuronides Exert Anti-inflammatory Effects by Suppressing Interferon β and Inducible Nitric Oxide Synthase Expression through Deconjugation in Macrophage-like J774.1 Cells

Sesamin, a representative sesame lignan, has health-promoting activities. Sesamin is converted into catechol derivatives and further into their glucuronides or sulfates in vivo, whereas the biological activities of sesamin metabolites remain unclear. We examined the inhibitory effects of sesamin metabolites on the lipopolysaccharide (LPS)-induced nitric oxide (NO) production in mouse macrophage-like J774.1 cells and found that a monocatechol derivative SC1, (7α,7'α,8α,8'α)-3,4-dihydroxy-3',4'-methylenedioxy-7,9':7',9-diepoxylignane, has a much higher activity than sesamin and other metabolites. The inhibitory effects of SC1 glucuronides were time-dependently enhanced, associated with the intracellular accumulation of SC1 and the methylated form. SC1 glucuronides and SC1 attenuated the expression of inducible NO synthase (iNOS) and upstream interferon-β (IFN-β) in the LPS-stimulated macrophages. The inhibitory effects of SC1 glucuronides against NO production were canceled by the β-glucuronidase inhibitor and enhanced by the catechol-O-methyltransferase inhibitor. Our results suggest that SC1 glucuronides exert the anti-inflammatory effects by inhibiting the IFN-β/iNOS signaling through macrophage-mediated deconjugation.

Recovery of Sesamin, Sesamolin, and Minor Lignans From Sesame Oil Using Solid Support-Free Liquid-Liquid Extraction and Chromatography Techniques and Evaluation of Their Enzymatic Inhibition Properties

In this study, an integrated process for the recovery of sesamin and sesamolin, two high added-value lignans of sesame oil (SO) was developed, using synchronous extraction and chromatography techniques. The extraction of SO phenolic content was studied using two different extraction techniques: Annular centrifugal extraction (ACE) and centrifugal partition extraction (CPE). The derived data of each experiment were compared in terms of revealing the yields, time, and solvents consumption showing that CPE is the most effective technique, concerning the solvent consumption. The isolation of lignans was achieved using centrifugal partition chromatography (CPC) both on semi-preparative and preparative scale. The biphasic system used for this purpose consisted of the following solvents: n-Hex/EtOAc/EtOH/H₂O in proportion 2:3:3:2 (v/v/v/v) and direct recovery of the two major lignans sesamin and sesamolin was achieved. In parallel the CPC analysis resulted in the isolation of four minor lignans of sesame oil, i.e., samin, sesamol, sesaminol, and episesaminol. Structure elucidation of isolated lignans was based on HRMS/MS and NMR experiments. High-performance liquid chromatography (HPLC) was employed for quantitative analysis of the obtained extracts to determine the purity of the isolated compounds as well. The results of this study demonstrated that sesamin and sesamolin were recovered in purity higher than 95%, verifying the effectiveness of the purposed separation methodology. Finally, due to the general application of sesame oil in cosmetic industry, all the pure compounds were evaluated for their tyrosinase, elastase, collagenase, and hyaluronidase inhibition activity.

Effects of Composite Supplement Containing Astaxanthin and Sesamin on Cognitive Functions in People with Mild Cognitive Impairment: A Randomized, Double-Blind, Placebo-Controlled Trial

Background:

Dementia and its first or transitional stage, mild cognitive impairment (MCI), is a major concern for the aging Japanese society. Thus, the use of dietary supplements to improve or maintain cognitive function has become a topic of public interest.

Objective:

In this study, we evaluated the effects of a composite supplement containing food-derived antioxidants, specifically astaxanthin and sesamin (AS), on cognitive function in people with MCI.

Method:

Twenty-one healthy participants with MCI were recruited in our double-blind placebo-controlled pilot study. They were assigned to either an AS group, who received ingestible capsules containing AS, or a placebo group, who received identical placebo capsules. To assess cognitive functions, we performed the Japanese version of the Central Nervous System Vital Signs (CNSVS) test and the Alzheimer’s Disease Assessment Scale-Cog test at baseline, after 6 weeks, and after 12 weeks of dietary supplementation.

Results:

The CNSVS test revealed significant improvements in psychomotor speed and processing speed in the AS group compared with the placebo group, suggesting that the daily supplementation of AS improved cognitive functions related to the ability to comprehend, and perform complex tasks quickly and accurately.

Conclusion:

Our results provide support for the use of AS as a dietary supplementation for improving cognitive functions.

Sesamin Protects the Femoral Head From Osteonecrosis by Inhibiting ROS-Induced Osteoblast Apoptosis in Rat Model

Glucocorticoids intake has become the most common pathogenic factor for osteonecrosis of the femoral head (ONFH). Annually, tens of millions of patients suffer from pain related to ONFH. Researchers have proposed several underlying mechanisms of ONFH, including osteocyte apoptosis, cell differentiation disorder, and angiogenesis hindrance. Sesamin, isolated from Sesamum indicum seeds, was reported could affect osteocyte inflammation and differentiation in osteoarthritis and osteoporosis. We investigated the underlying influence of sesamin on ONFH rat model. Fifteen male Sprague-Dawley rats were randomly divided into three groups. The ONFH model group only received the methylprednisolone (MPS) and lipopolysaccharide (LPS) injection to promote the development of ONFH. The sesamin treatment group was injected with sesamin, MPS, and LPS. The control group was untreated. Rats from above groups were sacrificed 4 weeks later. The effect of sesamin on ONFH rats was validated by H&E staining. TUNEL staining showed that femoral head necrosis was attenuated by sesamin. Furthermore, the phosphorylation of Akt was increased and the downstream cellular apoptosis signal pathway was inhibited. Intracellular ROS level was decreased after sesamin treatment. In conclusion, our findings suggest that sesamin protects the femoral head from osteonecrosis by inhibiting ROS-induced osteoblast apoptosis.

[Metabolism of Sesamin and Drug-Sesamin Interaction]

　Sesamin, derived from sesame seeds, is known to have various biological effects. Since some of these effects appear to be derived from its metabolites, the elucidation of sesamin metabolism is essential to understanding the molecular mechanism of its effects. In addition, it is important to clarify drug-sesamin interactions in order to address safety concerns, as some food factors are known to affect drug metabolism. Our previous studies revealed that sesamin was sequentially metabolized by cytochrome P450 (CYP) and UDP-glucuronosyltransferase or sulfotransferase. Whereas sesamin metabolism is mainly mediated by CYP2C9 in human liver, sesamin causes a mechanism-based inhibition (MBI) of CYP2C9. However, we found that the metabolite-intermediate complex between CYP2C9 and sesamin was unstable, and the effects of sesamin appeared to be minimal. To confirm this assumption, in vivo studies using rats were conducted. After the administration of sesamin to rats for 3 d, diclofenac (an NSAID) was administered to measure the time course of plasma concentration of diclofenac. No significant differences were observed in the diclofenac C_max, T_max, and AUC_{0-24 h} between the group that was administered sesamin and the group that was not. Based on these results, it could be concluded that no significant interaction occurs in people who take sesamin supplements at a standard dose.