Sesame oil attenuates nutritional fibrosing steatohepatitis by modulating matrix metalloproteinases-2, 9 and PPAR-γ

SIRT3 Activation a Promise in Drug Development? New Insights into SIRT3 Biology and Its Implications on the Drug Discovery Process

Sirtuins catalyze deacetylation of lysine residues with a NAD+-dependent mechanism. In mammals, the sirtuin family is composed of seven members, divided into four subclasses that differ in substrate specificity, subcellular localization, regulation, as well as interactions with other proteins, both within and outside the epigenetic field. Recently, much interest has been growing in SIRT3, which is mainly involved in regulating mitochondrial metabolism. Moreover, SIRT3 seems to be protective in diseases such as age-related, neurodegenerative, liver, kidney, heart, and metabolic ones, as well as in cancer. In most cases, activating SIRT3 could be a promising strategy to tackle these health problems. Here, we summarize the main biological functions, substrates, and interactors of SIRT3, as well as several molecules reported in the literature that are able to modulate SIRT3 activity. Among the activators, some derive from natural products, others from library screening, and others from the classical medicinal chemistry approach.

The protective effects of sesamol and/or the probiotic, Lactobacillus rhamnosus, against aluminum chloride-induced neurotoxicity and hepatotoxicity in rats: Modulation of Wnt/β-catenin/GSK-3β, JAK-2/STAT-3, PPAR-γ, inflammatory, and apoptotic pathways

Introduction: Aluminium (Al) is accumulated in the brain causing neurotoxicity and neurodegenerative disease like Alzheimer's disease (AD), multiple sclerosis, autism and epilepsy. Hence, attenuation of Al-induced neurotoxicity has become a "hot topic" in looking for an intervention that slow down the progression of neurodegenerative diseases. Objective: Our study aims to introduce a new strategy for hampering aluminum chloride (AlCl3)-induced neurotoxicity using a combination of sesamol with the probiotic bacteria; Lactobacillus rhamnosus (L. rhamnosus) and also to test their possible ameliorative effects on AlCl3-induced hepatotoxicity. Methods: Sprague-Dawley male rats were randomly divided into five groups (n = 10/group) which are control, AlCl3, AlCl3 + Sesamol, AlCl3 + L. rhamnosus and AlCl3 + Sesamol + L. rhamnosus. We surveilled the behavioral, biochemical, and histopathological alterations centrally in the brain and peripherally in liver. Results: This work revealed that the combined therapy of sesamol and L. rhamnosus produced marked reduction in brain amyloid-β, p-tau, GSK-3β, inflammatory and apoptotic biomarkers, along with marked elevation in brain free β-catenin and Wnt3a, compared to AlCl3-intoxicated rats. Also, the combined therapy exerted pronounced reduction in hepatic expressions of JAK-2/STAT-3, inflammatory (TNF-α, IL-6, NF-κB), fibrotic (MMP-2, TIMP-1, α-SMA) and apoptotic markers, (caspase-3), together with marked elevation in hepatic PPAR-γ expression, compared to AlCl3 -intoxicated rats. Behavioral and histopathological assessments substantiated the efficiency of this combined regimen in halting the effect of neurotoxicity. Discussion: Probiotics can be used as an add-on therapy with sesamol ameliorate AlCl3 -mediated neurotoxicity and hepatotoxicity.

Ameliorative effect of sesame oil on experimentally induced polycystic ovary syndrome: A cross-link between XBP-1/PPAR-1, regulatory proteins for lipogenesis/steroids

Polycystic ovary syndrome (PCOS) is a mixed endocrine/metabolic/reproductive disorder in women of reproductive age. Sesame oil (SO) contains sesame lignans & vitamin E with broad-spectrum antioxidant and anti-inflammatory effects. This study investigates the ameliorative effect of SO on experimentally induced PCOS and elucidates the possible molecular mechanisms with a deeper focus on the different signaling pathways involved. The study was carried out on 28 nonpregnant female Wister albino rats that were divided into four equal groups; Group I (control group) received oral 0.5% wt/vol carboxymethyl cellulose daily. Group II (SO group): orally administered SO (2 mL/kg body wt./day) for 21 days. Group III (PCOS group) received letrozole daily, 1 mg/kg, for 21 days. Group IV (PCOS + SO group): concomitantly administered letrozole and SO for 21 days. The serum hormonal and metabolic panel and the homogenate ATF-1, StAR, MAPK, PKA, and PI3K levels of the ovarian tissue were calorimetrically evaluated. However, endoplasmic reticulum (ER) stress was evaluated by ovarian XBP1 and PPAR-γ messenger RNA expression level using the qRT-PCR technique. Ovarian COX-2 was detected immunohistochemically. The results suggest that SO-treated PCOS rats showed a significantly improved hormonal, metabolic panel, inflammatory, and ER stress status with concomitant decreases in ATF-1, StAR, MAPK, PKA, and PI3K in ovarian rats compared to the correspondent values in PCOS without treatment. CONCLUSIONS: The protective effects of SO against PCOS are triggered by ameliorating regulatory proteins of ER stress, lipogenesis, and steroidogenesis through the PI3K/PKA and MAPK/ERK2 signaling cascades. SIGNIFICANCE STATEMENT: Polycystic ovary syndrome (PCOS) is the most common mixed endocrine-metabolic dysfunction among women within the reproductive period, with an estimated prevalence of 5%-26% worldwide. Doctors traditionally recommend metformin for PCOS patients. However, metformin is known to be associated with significant adverse effects and contraindications. This work aimed at shedding light on the ameliorative effect of sesame oil (SO), natural polyunsaturated fatty acids-rich oil, on the induced PCOS model. SO proved to have a marvelous effect on the metabolic and endocrine derangements in the PCOS rat model. We hoped to provide a valuable alternative treatment for PCOS patients to avoid the side effects of metformin and to help PCOS patients for whom metformin is contraindicated.

Food and nutraceutical functions of sesame oil: An underutilized crop for nutritional and health benefits

Sesame is the oldest oilseed crop known to humanity, though it contributes a small share in the global vegetable oil production. Sesame oil contains nutrients, including lignans, tocopherols, phytosterols, natural antioxidants, and bioactive compounds. It provides various health benefits such as anti-lipogenic, hypo-cholesterolemic, anti-degenerative, and neural health-promoting properties. Being an under-utilized minor crop, it has not received enough research attention for its food and nutraceutical potential. The sesame crop is a potential candidate to maintain the diversity of food oils and harness its benefits for improving human health. The present review will provide detailed research on sesame oil contents, health effects, nutraceuticals, oil quality, and value addition strategies. Also, the sesame oil nutritional quality was compared with other vegetable oils, highlighting the potential health and nutrition-related benefits. The way forward for further sesame improvement through value addition traits was also discussed.

The effect of sesame oil consumption compared to sunflower oil on lipid profile, blood pressure, and anthropometric indices in women with non-alcoholic fatty liver disease: a randomized double-blind controlled trial

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is one of the most common liver diseases in the world. There is strong evidence that dyslipidemia and other cardio-metabolic disorders are highly prevalent in patients with NAFLD. This trial aimed at examining the effect of sesame oil (SO) in the context of a weight loss program on lipid profile, blood pressure, and anthropometric indices in women with NAFLD.

METHODS

This randomized, double-blind, controlled trial was carried out on 60 women with NAFLD. Subjects were randomly assigned to the SO group (n = 30) and sunflower oil (SFO) group (n = 30), each person consuming 30 g of oil per day for 12 weeks. All the participants received a hypocaloric diet (- 500 kcal/day) during the study. Lipid profile, blood pressure, and anthropometric indices were assessed at pre- and post-intervention phases.

RESULTS

In total, 53 participants completed the study. Following 12 weeks of intervention, anthropometric indices (p < 0.001) and systolic blood pressure (SBP) (p < 0.05) were significantly decreased in both groups and diastolic blood pressure (DBP) was significantly decreased in So group (p = 0.03). There was no significant change in lipid profile in both groups (p > 0.05). After adjusting for confounders, DBP (p = 0.031) and total cholesterol (TC) divided by high-density lipoprotein cholesterol (HDL-C) (p = 0.039) in the SO group were significantly reduced compared to the SFO group (p < 0.05).

CONCLUSIONS

The present clinical trial revealed that SO and SFO may not differently affect anthropometric indices, SBP, and lipid profile except for TC/HDL-C. In addition, SO may be effective in improvement of DBP and TC/HDL-C compared to the SFO group.

TRIAL REGISTRATION

Ethical approval of this trial was obtained at Isfahan University of Medical Sciences with the reference number of IR.MUI.

RESEARCH

REC.1399.548 ( https://ethics.

RESEARCH

ac.ir/ProposalCertificateEn.php?id=158942&Print=true&NoPrintHeader=true&NoPrintFooter=true&NoPrintPageBorder=true&LetterPrint=true ), and it was registered before the start of the patient recruitment on December 12th, 2020 in the Iranian Registry of Clinical Trials (IRCT) with the registration number of IRCT20140208016529N6 .

Sesame Oil Ameliorates Alanine Aminotransferase, Aspartate Aminotransferase, and Fatty Liver Grade in Women with Nonalcoholic Fatty Liver Disease Undergoing Low-Calorie Diet: A Randomized Double-Blind Controlled Trial

Background

The type and amount of dietary fats play an important role in fat accumulation in the liver. Sesame oil (SO) is a good source of monounsaturated acids (MUFAs) and polyunsaturated fatty acids (PUFAs).

Objective

This trial aimed at examining the effect of SO consumption on the levels of liver enzymes and the severity of fatty liver in women with nonalcoholic fatty liver disease (NAFLD) undergoing a weight loss diet.

Methods

This randomized, double-blind, controlled trial was carried out on 60 women with NAFLD. Subjects were randomly assigned to the SO group (n = 30) and sunflower oil (SFO) group (n = 30), each person consuming 30 grams of oil per day for 12 weeks. All the participants received a hypocaloric diet (-500 kcal/day) during the study. Fatty liver grade and liver enzymes were assessed at pre- and postintervention phases.

Results

53 patients completed the study. Significant reductions in body weight, body mass index (BMI), waist circumference (WC), and fatty liver grade were observed in both groups (P < 0.05). Following SO, significant decreases in serum aspartate and alanine aminotransferases (AST and ALT) were observed. After adjusting for confounders, ALT, AST, and fatty liver grade of the SO group were significantly reduced compared to the SFO group (P < 0.05). However, the changes in serum alkaline phosphatase (ALP) were not significant (P > 0.05).

Conclusions

The desired effects of weight loss were reinforced by the consumption of SO through improving fatty liver severity and serum ALT and AST levels in NAFLD patients. Moreover, low-calorie diets may lead to favorable outcomes for NAFLD patients through mitigation of obesity and fatty liver grade.

Sesame oil mitigates memory impairment, oxidative stress, and neurodegeneration in a rat model of Alzheimer's disease. A pivotal role of NF-κB/p38MAPK/BDNF/PPAR-γ pathways

ETHNOPHARMACOLOGICAL RELEVANCE

Sesame (Sesamum indicum, L., Family: Pedaliaceae) is a notable folk medicine in Middle East, Asia and Africa. Many traditional and pharmacological studies have documented the unique nature of sesame oil (SO). SO has been reported to have many pharmacological effects related to the anti-inflammatory and antioxidant capacity of its components. Neuroinflammation and oxidative stress have been the predominant pathogenic events in Alzheimer's disease (AD) which is one of the most common neurodegenerative diseases.

AIM OF STUDY

we aimed to explore the neuroprotective effect and the probable mechanisms of SO against aluminium chloride (AlCl3)-induced AD symptoms.

MATERIALS AND METHODS

Rats were treated daily with AlCl3 (100 mg/kg/i.p.) either alone or with SO (two different doses) for six weeks. Behavioral (Open-field and Morris water maze tests), histopathological, and biochemical examinations were used to evaluate the neuroprotective effect and the underlying mechanisms of SO against AlCl3-induced AD symptoms.

RESULTS

Our results indicated that SO significantly improved learning and memory impairments induced by AlCl3. Indeed, SO treatment significantly restored the elevated level of acetylcholinesterase (AChE) and amyloid beta (Aβ) overexpression. Moreover, AlCl3 treatment afforded histopathological changes, increase the expression of tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) in addition to mitigation of oxidative stress status in the brain. SO abolished all these abnormalities. Meanwhile, AlCl3 induced activation of p38 mitogen-activated protein kinase (p38MAPK) and decreased brain-derived neurotrophic factor (BDNF) which were inhibited by SO. Furthermore, SO administration modulated the expression of the peroxisome proliferator-activated receptor gamma (PPAR-γ) and nuclear factor kappa B (NF-κB).

CONCLUSIONS

In conclusion, the neuroprotective effect of SO involved the modulation of different mechanisms targeting oxidative stress, neuroinflammation, and cognitive functions. SO may modulate different molecular targets involved in AD pathogenesis by alterations of NF-κB/p38MAPK/BDNF/PPAR-γ signalling and this may be attributed to the synergistic effect of their active components.

Anti-Inflammatory and Anticancer Properties of Bioactive Compounds from Sesamum indicum L.-A Review

The use of foodstuff as natural medicines has already been established through studies demonstrating the pharmacological activities that they exhibit. Knowing the nutritional and pharmacological significance of foods enables the understanding of their role against several diseases. Among the foods that can potentially be considered as medicine, is sesame or Sesamum indicum L., which is part of the Pedaliaceae family and is composed of its lignans such as sesamin, sesamol, sesaminol and sesamolin. Its lignans have been widely studied and are known to possess antiaging, anticancer, antidiabetes, anti-inflammatory and antioxidant properties. Modern chronic diseases, which can transform into clinical diseases, are potential targets of these lignans. The prime example of chronic diseases is rheumatic inflammatory diseases, which affect the support structures and the organs of the body and can also develop into malignancies. In line with this, studies emphasizing the anti-inflammatory and anticancer activities of sesame have been discussed in this review.

Sesamol Induces Human Hepatocellular Carcinoma Cells Apoptosis by Impairing Mitochondrial Function and Suppressing Autophagy

Sesamol, a nutritional phenolic antioxidant compound enriched in sesame seeds, has been shown to have potential anticancer activities. This study aims at characterizing the antitumor efficacy of sesamol and unveiling the importance of mitochondria in sesamol-induced effects using a human hepatocellular carcinoma cell line, HepG2 cells. Results of this study showed that sesamol treatment suppressed colony formation, elicited S phase arrest during cell cycle progression, and induced both intrinsic and extrinsic apoptotic pathway in vitro with a dose-dependent manner. Furthermore, sesamol treatment elicited mitochondrial dysfunction by inducing a loss of mitochondrial membrane potential. Impaired mitochondria and accumulated H2O2 production resulted in disturbance of redox-sensitive signaling including Akt and MAPKs pathways. Mitochondrial biogenesis was inhibited as suggested by the decline in expression of mitochondrial complex I subunit ND1, and the upstream AMPK/PGC1α signals. Importantly, sesamol inhibited mitophagy and autophagy through impeding the PI3K Class III/Belin-1 pathway. Autophagy stimulator rapamycin reversed sesamol-induced apoptosis and mitochondrial respiration disorders. Moreover, it was also shown that sesamol has potent anti-hepatoma activity in a xenograft nude mice model. These data suggest that mitochondria play an essential role in sesamol-induced HepG2 cells death, and further research targeting mitochondria will provide more chemotherapeutic opportunities.

Cereal Lignans, Natural Compounds of Interest for Human Health?

Cereals are suggested to be the most important sources of lignan in the diets of western populations. Recent epidemiological studies show that European subpopulations in which the major source of lignans are cereals, display lower disease frequency regarding metabolic and cardiovascular diseases. The biological mechanisms of lignan are several. Beyond their antioxidant and anti-inflammatory actions at nutritional doses some lignans regulate the activity of specific nuclear receptors (NRs), such as the estrogen receptors (ERs), and also NRs that are central switches in glucose and fatty acid metabolism such as PPARα, PPARγ and LXRs, highlighting them as selective nuclear receptor modulators (SNRMs). These include enterodiol (END) and enterolactone (ENL), the metabolites produced by the gut microbiota from food lignans. The available knowledge suggests that given some additional research it should be possible to make ‘function' claims for a regular intake of lignans-rich foods related to maintaining a healthy metabolism.

Comparative transcriptome profiling of the fertile and sterile flower buds of a dominant genic male sterile line in sesame (Sesamum indicum L.)

BACKGROUND

Sesame (Sesamum indicum L.) is a globally important oilseed crop with highly-valued oil. Strong hybrid vigor is frequently observed within this crop, which can be exploited by the means of genic male sterility (GMS). We have previously developed a dominant GMS (DGMS) line W1098A that has great potential for the breeding of F₁ hybrids. Although it has been genetically and anatomically characterized, the underlying molecular mechanism for male sterility remains unclear and therefore limits the full utilization of such GMS line. In this study, RNA-seq based transcriptome profiling was carried out in two near-isogenic DGMS lines (W1098A and its fertile counterpart, W1098B) to identify differentially expressed genes (DEGs) related to male sterility.

RESULTS

A total of 1,502 significant DEGs were detected, among which 751 were up-regulated and 751 were down-regulated in sterile flower buds. A number of DEGs were implicated in both ethylene and JA synthesis & signaling pathway; the expression of which were either up- or down-regulated in the sterile buds, respectively. Moreover, the majority of NAC and WRKY transcription factors implicated from the DEGs were up-regulated in sterile buds. By querying the Plant Male Reproduction Database, 49 sesame homologous genes were obtained; several of these encode transcription factors (bHLH089, MYB99, and AMS) that showed reduced expression in sterile buds, thus implying the possible role in specifying or determining tapetal fate and development. The predicted effect of allelic variants on the function of their corresponding DEGs highlighted several Insertions/Deletions (InDels), which might be responsible for the phenotype of sterility/fertility in DGMS lines.

CONCLUSION

The present comparative transcriptome study suggested that both hormone signaling pathway and transcription factors control the male sterility of DGMS in sesame. The results also revealed that several InDels located in DEGs prone to cause loss of function, which might contribute to male sterility. These findings provide valuable genomic resources for a deeper insight into the molecular mechanism underlying DGMS.

Fatty liver disease induced by perfluorooctane sulfonate: Novel insight from transcriptome analysis

Perfluorooctane sulfonate (PFOS), a hepato-toxicant and potential non-genotoxic carcinogen, was widely used in industrial and commercial products. Recent studies have revealed the ubiquitous occurrence of PFOS in the environment and in humans worldwide. The widespread contamination of PFOS in human serum raised concerns about its long-term toxic effects and its potential risks to human health. Using fatty liver mutant foie gras (fgr(-/-))/transport protein particle complex 11 (trappc11(-/-)) and PFOS-exposed wild-type zebrafish embryos as the study model, together with RNA sequencing and comparative transcriptomic analysis, we identified 499 and 1414 differential expressed genes (DEGs) in PFOS-exposed wild-type and trappc11 mutant zebrafish, respectively. Also, the gene ontology analysis on common deregulated genes was found to be associated with different metabolic processes such as the carbohydrate metabolic process, glycerol ether metabolic process, mannose biosynthetic process, de novo' (Guanosine diphosphate) GDP-l-fucose biosynthetic process, GDP-mannose metabolic process and galactose metabolic process. Ingenuity Pathway Analysis further highlighted that these deregulated gene clusters are closely related to hepatitis, inflammation, fibrosis and cirrhosis of liver cells, suggesting that PFOS can cause liver pathogenesis and non-alcoholic fatty liver disease in zebrafish. The transcriptomic alterations revealed may serve as biomarkers for the hepatotoxic effect of PFOS.

Daily sesame oil supplementation mitigates ketoconazole-induced oxidative stress-mediated apoptosis and hepatic injury

Ketoconazole (KCZ) is the most commonly used systemic antifungal drug. However, long-term treatment of KCZ induces hepatic injury. Oxidative stress is involved in KCZ-induced hepatic injury. Oxidative stress plays an important role in apoptosis-associated hepatic damage. Sesame oil is rich in potent antioxidants and antifungal constituents. It attenuates hepatic injury by inhibiting oxidative stress. Thus, sesame oil may protect against KCZ-induced oxidative stress, apoptosis and hepatic damage. The aim of the present study was to investigate the protective effect of sesame oil as a nutritional supplement on KCZ-induced hepatic injury in mice. KCZ (300 mg/kg/day) was administered by gastric intubation; 30 min later, sesame oil (0, 0.0625, 0.125, 0.25 or 0.5 ml/kg/day; p.o.) was administered to mice for 14 days. Blood and liver tissue were collected. Hepatic injury was evaluated by serum biochemistry and histology. Oxidative stress was evaluated by myeloperoxidase activity, p47-phox, reactive oxygen species generation, lipid peroxidation and glutathione level. Apoptosis was evaluated by p53, caspase-3, Bcl-2, Bax and Cyto-C expression. Osteopontin was measured to assess liver healing. Sesame oil attenuated hepatic injury; it also decreased oxidative stress and apoptosis in KCZ-treated mice. Sesame oil may be used as a nutritional supplement with existing antifungal therapies to neutralize the adverse hepatotoxic nature of antifungal drugs by attenuating hepatic apoptosis through redox system to protect and heal liver injury in KCZ-treated mice.

Curative effect of sesame oil in a rat model of chronic kidney disease

AIM

Chronic kidney disease causes a progressive and irreversible loss of renal function. We investigated the curative effect of sesame oil, a natural, nutrient-rich, potent antioxidant, in a rat model of chronic kidney disease.

METHODS

Chronic kidney disease was induced by subcutaneously injecting uni-nephrectomized rats with deoxycorticosterone acetate (DOCA) and 1% NaCl [DOCA/salt] in drinking water. Four weeks later, the rats were gavaged with sesame oil (0.5 or 1 mL/kg per day) for 7 days. Renal injury, histopathological changes, hydroxyl radical, peroxynitrite, lipid peroxidation, Nrf2, osteopontin expression, and collagen were assessed 24 h after the last dose of sesame oil.

RESULTS

Blood urea nitrogen, creatinine, urine volume, and albuminuria were significantly higher in the DOCA/salt treated rats than in control rats. Sesame oil significantly decreased these four tested parameters in DOCA/salt treated rats. In addition, creatinine clearance rate and nuclear Nrf2 expression were significantly decreased in the DOCA/salt treated rats compared to control rats. Sesame oil significantly decreased hydroxyl radical, peroxynitrite level, lipid peroxidation, osteopontin, and renal collagen deposition, but increased creatinine clearance rate and nuclear Nrf2 expression in DOCA/salt treated rats.

CONCLUSION

We conclude that supplementation of sesame oil mitigates DOCA/salt induced chronic kidney disease in rats by activating Nrf2 and attenuating osteopontin expression and inhibiting renal fibrosis in rats.

Protective effects of sesamin on liver fibrosis through antioxidative and anti-inflammatory activities in rats

CONTEXT

Sesamin (Ses) from Sesamun indicum seeds has potent antioxidants and anti-inflammatory effects.

OBJECTIVE

This study focused on the antioxidant and anti-inflammatory effects of Ses on Carbon tetrachloride (CCl4)-induced hepatic fibrosis in experimental rats and the potential mechanism underlying the activation of NF-kB pathway.

MATERIALS AND METHODS

Hepatic fibrosis was induced by interaperitoneally (i.p.) administered with 20% CCl4 in corn oil (2 mL/kg for 8 weeks) in rats. After 8 weeks, activities of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total bilirubin (TBIL) were checked. The levels of protein carbonyls and antioxidant enzymes such as superoxide dismutase (SOD) and GSH-Px were determined after Ses administration. H&E and Masson's trichrome staining for histopathological changes of liver tissues were observed. Western blotting was used to detect expression of IL-6, cyclooxygenase-2 (COX-2), and NF-kB activation. Finally, the levels of hydroxyproline in liver tissues were also determined.

RESULTS

Ses decreased the release of liver enzymes - ALT, AST, and TBIL, reduced protein carbonyls, attenuated the reduction of SOD and GSH-Px activities induced by CCl4 in the liver tissue. It also significantly reduced the levels IL-6 and COX-2 in the liver caused by CCl4 by inhibition of NF-kB activation. Histological results indicated that Ses significantly improved the pathological lesions of liver fibrosis.

CONCLUSIONS

Ses exerted hepatoprotective effects possibly due to the antioxidant effect and suppressing the NF-kB activation.

Sesamin Ameliorates High-Fat Diet-Induced Dyslipidemia and Kidney Injury by Reducing Oxidative Stress

The study explored the protective effect of sesamin against lipid-induced renal injury and hyperlipidemia in a rat model. An animal model of hyperlipidemia was established in Sprague-Dawley rats. Fifty-five adult Sprague-Dawley rats were divided into five groups. The control group was fed a standard diet, while the other four groups were fed a high-fat diet for 5 weeks to induce hyperlipidemia. Three groups received oral sesamin in doses of 40, 80, or 160 mg/(kg·day). Seven weeks later, the blood lipids, renal function, antioxidant enzyme activities, and hyperoxide levels in kidney tissues were measured. The renal pathological changes and expression levels of collagen type IV (Col-IV) and α-smooth muscle actin (α-SMA) were analyzed. The administration of sesamin improved the serum total cholesterol, triglyceride, low-density lipoprotein cholesterol, apolipoprotein-B, oxidized-low-density lipoprotein, and serum creatinine levels in hyperlipidemic rats, while it increased the high-density lipoprotein cholesterol and apolipoprotein-A levels. Sesamin reduced the excretion of 24-h urinary protein and urinary albumin and downregulated α-SMA and Col-IV expression. Moreover, sesamin ameliorated the superoxide dismutase activity and reduced malondialdehyde levels in kidney tissue. Sesamin could mediate lipid metabolism and ameliorate renal injury caused by lipid metabolism disorders in a rat model of hyperlipidemia.

Sesamin Inhibits PDGF-Mediated Proliferation of Vascular Smooth Muscle Cells by Upregulating p21 and p27

Sesamin, an active ingredient of Asiasarum heterotropoides, is known to exhibit many bioactive functions, but the effect thereof on vascular smooth muscle cell (VSMC) proliferation remains poorly understood. Hence, we explored the antiproliferative action of sesamin on VSMCs and the underlying mechanism thereof, focusing on possible effects of sesamin on cell cycle progression. Sesamin significantly inhibited platelet-derived growth factor (PDGF)-induced VSMC proliferation (inhibition percentage at 1, 5, and 10 μM sesamin was 49.8 ± 22.0%, 74.6 ± 19.9%, and 87.8 ± 13.0%, respectively) in the absence of cytotoxicity and apoptosis, and PDGF-induced DNA synthesis; and arrested cell cycle progression in the G0/G1-to-S phase. Sesamin potently inhibited cyclin D1 and CDK4 expression, pRb phosphorylation, and expression of the proliferating cell nuclear antigen (PCNA); and upregulated p27(KIP1), p21(CIP1), and p53. The results thus indicate that the antiproliferative effect of sesamin on PDGF-stimulated VSMCs is attributable to arrest of the cell cycle in G0/G1 caused, in turn, by upregulation of p27(KIP1), p21(CIP1), and p53, and inhibition of cyclin E-CDK2 and cyclin D1-CDK4 expression.

The effect of sesamin on airway fibrosis in vitro and in vivo

Airway fibrosis, which is a crucial pathological condition occurring in various types of pulmonary disorders, is characterized by accumulation and activation of fibroblast cells, deposition of extracellular matrix (ECM) proteins, and increase of airway basement membrane. Transforming growth factor beta 1 (TGF-β1) is the principal profibrogenic cytokine that is responsible for fibrotic responses. In the present study, we aimed to investigate the antifibrotic effects of the natural polyphenolic compound, sesamin, on TGF-β1-induced fibroblast proliferation and activation, epithelial-mesenchymal transition (EMT), and ovalbumin (OVA)-induced airway fibrosis in vivo. We found that sesamin attenuated TGF-β1-induced proliferation of cultured lung fibroblasts. Sesamin inhibited TGF-β1-stimulated expression of alpha smooth muscle actin (α-SMA), suggesting that sesamin plays an inhibitory role in fibroblast activation. Sesamin blocked upregulation of the mesenchymal markers (fibronectin and vimentin) and downregulation of the epithelial marker (E-cadherin), indicating an inhibitory effect on TGF-β1-induced EMT in A549 cells. TGF-β1-induced Smad3 phosphorylation was also significantly reduced by sesamin in both cultured fibroblast and A549 cells. In the airway fibrosis induced by OVA in mice, sesamin inhibited the accumulation of α-SMA-positive cells and expression of collagen I in the airway. Histological studies revealed that sesamin protected against subepithelial fibrosis by reducing myofibroblast activation and collagen accumulation in the ECM. OVA-induced thickening of basement membrane was significantly alleviated in animals receiving sesamin treatments. These results suggest a therapeutic potential of sesamin as an antifibrotic agent.

Sesamin enhances cholesterol efflux in RAW264.7 macrophages

Foam cells formation as a result of the uncontrolled cytophagy of modified cholesterol by macrophages plays a key role in the occurrence and development of atherosclerosis. Sesamin is an active constituent of Sesamum indicum which has been shown to possess multiple pharmacological activities. In this work, we investigated the effects of sesamin on foam cell formation and cholesterol efflux in RAW264.7 macrophages. Sesamin dose-dependently inhibited the enhanced cholesterol accumulation elicited by oxidized low-density lipoprotein cholesterol (oxLDL) in RAW264.7 cells. Treatment with sesamin (10 μM) significantly enhanced cholesterol efflux mediated by high-density lipoprotein (HDL). Realtime quantitative PCR and luciferase assays showed that sesamin significantly increased the mRNA levels of PPARγ, LXRα, and ABCG1, and increased the transcriptional activity of PPARγ. The stimulating effect of sesamin on cholesterol efflux was substantially inhibited by the co-treatment with GW9662, a potent inhibitor of PPARγ. These results suggest that sesamin is a new inhibitor of foam cell formation that may stimulate cholesterol efflux through upregulation of the PPARγ-LXRα-ABCG1 pathway.