Therapeutic potential of plant polyphenols in acute pancreatitis

Acute pancreatitis is a potentially life-threatening inflammatory disorder of the exocrine pancreas characterized by early activation of pancreatic enzymes followed by macrophage-driven inflammation, and pancreatic acinar cell death. The most common causes are gallstones and excessive alcohol consumption. Inflammation and oxidative stress play critical roles in its pathogenesis. Despite increasing incidence, currently, no specific drug therapy is available to treat or prevent acute pancreatitis, in particular severe acute pancreatitis. New therapeutic agents are very much needed. Plant polyphenols have attracted extensive attention in the field of acute pancreatitis due to their diverse pharmacological properties. In this review, we discuss the potential of plant polyphenols in inhibiting the occurrence and development of acute pancreatitis via modulation of inflammation, oxidative stress, calcium overload, autophagy, and apoptosis, based on the currently available in vitro, in vivo animal and very few clinical human studies. We also outline the opportunities and challenges in the clinical translation of plant polyphenols for the treatment of the disease. We concluded that plant polyphenols have a potential therapeutic effect in the management and treatment of acute pancreatitis. Knowledge gained from this review will hopefully inspire new research ideas and directions for the development and application of plant polyphenols for treating this disease.

Sesamol as a potent anticancer compound: from chemistry to cellular interactions

Sesamol (SM), a well-known component isolated from sesame seeds (Sesamum indicum), used in traditional medicines in treating numerous ailments. However, numerous molecular investigations revealed the various mechanisms behind its activity, emphasizing its antiproliferative, anti-inflammatory, and apoptosis-inducing properties, preventing cancer cell spread to distant organs. In several cells derived from various malignant tissues, SM-regulated signal transduction pathways and cellular targets have been identified. This review paper comprehensively describes the anticancer properties of SM and SM-viable anticancer drugs. Additionally, the interactions of this natural substance with standard anticancer drugs are examined, and the benefits of using nanotechnology in SM applications are explored. This makes SM a prime example of how ethnopharmacological knowledge can be applied to the development of contemporary drugs.

Sesamol induces cytotoxicity via mitochondrial apoptosis in SCC-25 cells

Sesamol is the main constituent of sesame seed oil and is obtained from Sesamum indicum. Oral squamous cell carcinoma (OSCC) is one of the most common neoplasms affecting the oral cavity. In this study, we investigated the cytotoxic potentials of sesamol on human oral squamous carcinoma (SCC-25) cells. Human oral squamous carcinoma cells were treated with different concentrations (62.5, 125, and 250 μM/mL) of sesamol for 24 h. Cytotoxicity was analyzed by 3- (4, 5- dimethylthiazol -2- yl) -2, 5-diphenyltetrazolium bromide (MTT) assay. Intracellular reactive oxygen species (ROS) expression was investigated by dichloro-dihydro-fluorescein diacetate assay. Apoptosis-related morphology was analyzed by acridine orange/ethidium bromide staining. Caspase-9 expression was analyzed by confocal microscopic double immunofluorescence staining. Mitochondrial apoptosis-related markers are analyzed using qPCR. Sesamol treatment caused a significant cytotoxic effect in OSCC cells. Sesamol-induced cytotoxic effect was associated with intracellular ROS generation. Sesamol treatments induced a significant increase in the early and late apoptotic cells. This treatment also induced caspase-9 expression in OSCC cells. Sesamol treatments caused downregulation of Harvey rat sarcoma viral oncogene homolog (HRAS) expression at protein and gene levels. Sesamol treatment modulates intrinsic apoptotic marker gene expression in OSCC cells. Overall results confirm the anti-cancer potential of sesamol and it seems to be a promising candidate for OSCC.

Sesamol Upregulates Death Receptors and Acts as a Chemosensitizer in Solid Ehrlich Carcinoma Model in Mice

AIMS

The aim of the present study was to investigate the anti-tumor effect of sesamol (SML), a nutritional phenolic compound of sesame, in solid Ehrlich carcinoma (SEC) model in mice and its ability to enhance doxorubicin (DOX) anti-tumor activity. Moreover, we analyzed the ability of SML to protect against DOX-induced cardiotoxicity.

MAIN METHODS

SML (70 mg/kg), DOX (2 mg/kg) and their combination were given to mice bearing SEC for 21 day. The mRNA level of Fas, FasL, TRAILR2, TRAIL, caspase-3 and Bcl-2 were assessed by qPCR. Tumor and cardiac tissues were examined for histopathological changes by hematoxylin and eosin. Active caspase-3 was scored by immunohistochemical analysis.

KEY FINDINGS

SML treatment significantly decreased solid tumor size and weight. In addition, SML enhanced DOX anti-tumor activity. SML treatment either alone or in combination with DOX induced upregulation of Fas/FasL and TRAILR2/TRAIL gene expression. Moreover, SML increased caspase-3 protein and gene expressions and decreased Bcl-2 gene expression.

SIGNIFICANCE

SML upregulates death receptors expression and enhances apoptosis induction in tumor cells that may explain its anti-tumor activity. Not only that, but SML also enhances DOX anti-tumor activity and attenuates its cardiotoxicity.

Drug discovery and formulation development for acute pancreatitis

Acute pancreatitis is a sudden inflammation and only last for a short time, but might lead to a life-threatening emergency. Traditional drug therapy is an essential supportive method for acute pancreatitis treatment, yet, failed to achieve satisfactory therapeutic outcomes. To date, it is still challenging to develop therapeutic medicine to redress the intricate microenvironment promptly in the inflamed pancreas, and more importantly, avoid multi-organ failure. The understanding of the acute pancreatitis, including the causes, mechanism, and severity judgment, could help the scientists bring up more effective intervention and treatment strategies. New formulation approaches have been investigated to precisely deliver therapeutics to inflammatory lesions in the pancreas, and some even could directly attenuate the pancreatic damages. In this review, we will briefly introduce the involved pathogenesis and underlying mechanisms of acute pancreatitis, as well as the traditional Chinese medicine and the new drug option. Most of all, we will summarize the drug delivery strategies to reduce inflammation and potentially prevent the further development of pancreatitis, with an emphasis on the bifunctional nanoparticles that act as both drug delivery carriers and therapeutics.

Computationally Designed Sesamol Derivatives Proposed as Potent Antioxidants

Oxidative stress has been recognized to play an important role in several diseases, such as Parkinson's and Alzheimer's disease, which justifies the beneficial effects of antioxidants in ameliorating the deleterious effects of these health disorders. Sesamol, in particular, has been investigated for the treatment of several conditions because of its antioxidant properties. This article reports a rational computational design of new sesamol derivatives. They were constructed by adding four functional groups (-OH, -NH2, -COOH, and -SH) in three different positions of the sesamol molecular framework. A total of 50 derivatives between mono-, di-, and trisubstituted compounds were obtained. All the derivatives were evaluated and compared with a reference set of commercial neuroprotective drugs. The estimated properties are absorption, distribution, metabolism, excretion, toxicity, and synthetic accessibility. Selection and elimination scores were used to choose a first set of promising candidates. Acid-based properties and reactivity indexes were then estimated using the density functional theory. Four sesamol derivatives were finally selected, which are hypothesized to be potent antioxidants, even better than sesamol and Trolox for that purpose.

Sesamol protects MIN6 pancreatic beta cells against simvastatin-induced toxicity by restoring mitochondrial membrane potentials

Statins, the drugs for the treatment of dyslipidemia, have been suggested to impact insulin sensitivity, resulting in pancreatic β-cell dysfunction, and consequently, lead to new onset of diabetes. Taking this as a clue, the present study was designed to evaluate the protective effect of sesamol (a known antioxidant, antidiabetic and antidyslipidemic agent) against the diabetogenic potential of simvastatin. The toxic effects of simvastatin and sesamol on MIN6 insulinoma (Mouse pancreatic β cells) cells were evaluated separately by MTT assay. The protective effect of sesamol was evaluated at the IC₅₀ value of simvastatin at doses ranging from 7.8 to 62.5 micromolar (µM). Further, the reversal of the impact of simvastatin on cell cycle and mitochondrial membrane potential by sesamol pretreatment was studied. The IC₅₀ for simvastatin and sesamol were found to be 70.05 ± 2.34 μM and 2134 ± 8.41 μM, respectively, after 48 h and 72 h of incubation. Sesamol pretreatment protected the MIN6 cells from simvastatin toxicity (70 µM) in a dose-dependent manner from 7.8 to 31.25 µM. Simvastatin induced cell cycle arrest in G₀/G₁ phase. However, when cells were preincubated with sesamol for 24 h, a reversal in the cell cycle arrest was observed in simvastatin-treated cells (G₀/G₁). Pretreatment with sesamol also reduced the mitochondrial membrane potential loss compared to simvastatin treatment alone. These in vitro findings indicate that sesamol has a protective effect against simvastatin-induced toxicity on the pancreatic beta cells.

Sesamol, a major lignan in sesame seeds (Sesamum indicum): Anti-cancer properties and mechanisms of action

Sesamol is a natural phenolic compound and a major lignan isolated from sesame seeds (Sesamum indicum) and sesame oil. The therapeutic potential of sesamol was investigated intensively, and there is compelling evidence that sesamol acts as a metabolic regulator that possesses antioxidant, anti-mutagenic, anti-hepatotoxic, anti-inflammatory, anti-aging, and chemopreventive properties. Various studies have reported that sesamol exerts potent anti-cancer effects. Herein, we provide a comprehensive review that summarizes the in vitro and in vivo anti-cancer activity of sesamol in several cancer cell lines and animal models. The protective role that sesamol plays against oxidative stress through its radical scavenging ability and lipid peroxidation lowering potential is analyzed. The ability of sesamol to regulate apoptosis and various stages of the cell cycle is also outlined. Moreover, the signaling pathways that sesamol seems to target to execute its antioxidant, anti-inflammatory, and pro-apoptotic/anti-proliferative roles are discussed. The signaling pathways that sesamol targets include the p53, MAPK, JNK, PI3K/AKT, TNFα, NF-κB, PPARγ, caspase-3, Nrf2, eNOS, and LOX pathways. The mechanisms of action that sesamol executes to deliver its anti-cancer effects are delineated. In sum, there is ample evidence suggesting that sesamol possesses potent anti-cancer properties in vitro and in vivo. A thorough understanding of the molecular targets of sesamol and the mechanisms of action underlying its anti-cancer effects is necessary for possible employment of sesamol as a chemotherapeutic agent in cancer prevention and therapy.

Tea polyphenols ameliorates neural redox imbalance and mitochondrial dysfunction via mechanisms linking the key circadian regular Bmal1

Circadian rhythms are autonomous anticipatory oscillators that control a large array of physiological and metabolic processes. Compelling evidence points toward an interplay between circadian rhythms and cellular redox metabolism. Dysregulation of circadian rhythms is associated with neurodegenerative diseases and accelerated aging. Tea polyphenols (TP) is one of the most used antioxidants and exerts beneficial effect on neurodegenerative diseases. The aim of this study is to investigate whether circadian clock mechanisms are involved in the protection effect of TP against neural redox imbalance and mitochondrial dysfunction in SH-SY5Y cells. In the current study, our results revealed that TP, as a Bmal1-enhancing natural compound, can reverse the relatively shallow daily oscillations of circadian clock genes transcription and protein expression in SH-SY5Y neuronal cells under oxidative stress conditions. Furthermore, TP pretreatment significantly ameliorated H2O2-elicited mitochondria impairment via manipulating mitochondrial dynamics and mitochondrial membrane potential, which is consistent with the recovery in expression of mitochondrial respiration complex I-IV in Bmal1-dependent efficiency. Furthermore, Bmal1 is involved in TP-stimulated Nrf2/ARE/HO-1 and AKT/CREB/BDNF signaling pathway. Hence, TP may serve as a nutritional preventive strategy in the recovery of oxidative stress-related neurodegenerative disease via modulating circadian clock.

Sesamol ameliorates high-fat and high-fructose induced cognitive defects via improving insulin signaling disruption in the central nervous system

The present study demonstrated that sesamol prevents high-fat and high-fructose diet induced systemic insulin resistance and cognitive defects via stimulating PI3K/Akt signaling, improving ERK/CREB/BDNF cascades, and preserving mitochondrial function.

Protective Effects of Hydrogen Gas on Experimental Acute Pancreatitis

Acute pancreatitis (AP) is an inflammatory disease mediated by damage to acinar cells and pancreatic inflammation. In patients with AP, subsequent systemic inflammatory responses and multiple organs dysfunction commonly occur. Interactions between cytokines and oxidative stress greatly contribute to the amplification of uncontrolled inflammatory responses. Molecular hydrogen (H2) is a potent free radical scavenger that not only ameliorates oxidative stress but also lowers cytokine levels. The aim of the present study was to investigate the protective effects of H2 gas on AP both in vitro and in vivo. For the in vitro assessment, AR42J cells were treated with cerulein and then incubated in H2-rich or normal medium for 24 h, and for the in vivo experiment, AP was induced through a retrograde infusion of 5% sodium taurocholate into the pancreatobiliary duct (0.1 mL/100 g body weight). Wistar rats were treated with inhaled air or 2% H2 gas and sacrificed 12 h following the induction of pancreatitis. Specimens were collected and processed to measure the amylase and lipase activity levels; the myeloperoxidase activity and production levels; the cytokine mRNA expression levels; the 8-hydroxydeoxyguanosine, malondialdehyde, and glutathione levels; and the cell survival rate. Histological examinations and immunohistochemical analyses were then conducted. The results revealed significant reductions in inflammation and oxidative stress both in vitro and in vivo. Furthermore, the beneficial effects of H2 gas were associated with reductions in AR42J cell and pancreatic tissue damage. In conclusion, our results suggest that H2 gas is capable of ameliorating damage to the pancreas and AR42J cells and that H2 exerts protective effects both in vitro and in vivo on subjects with AP. Thus, the results obtained indicate that this gas may represent a novel therapy agent in the management of AP.

Effect of sesamol on the pathophysiological changes induced by surgical menopause in rodents

OBJECTIVE

Estrogen deprivation after menopause is associated with increased oxidative stress. The present study was designed to study the role of sesamol (3,4-methylenedioxyphenol), a phenolic antioxidant and anti-inflammatory molecule, in oxidative stress-induced changes in three major affected organ systems, the central nervous system, the cardiovascular system and the skeletal system in ovariectomized rats, a widely used animal model of menopause.

DESIGN

Animals were divided into eight different groups (n = 6-8). Five groups underwent ovariectomy; starting from the 2nd day of ovariectomy, three of these groups received sesamol (2, 4, 8 mg/kg) and the fourth group was administered α-tocopherol (100 mg/kg) orally for 7 weeks. The fifth ovariectomized group did not receive any drug treatment. Rats in the naïve (non-operated) and sham-operated groups did not receive any drug treatment, while the eighth group consisted of naïve animals which were treated for 7 weeks with only sesamol 8 mg/kg orally daily. After 7 weeks, animals were subjected to testing of behavioral paradigms (elevated plus maze and Morris water maze for assessment of anxiety and memory, respectively) 24 h after the last dose. After behavioral studies, animals were sacrificed for various biochemical estimations.

RESULT

Administration of sesamol (2, 4, 8 mg/kg orally) to ovariectomized rats for 7 weeks significantly and dose-dependently improved memory, attenuated anxiety, decreased oxidative stress in brain, improved the serum lipid profile and reduced serum tumor necrosis factor-α levels when compared with ovariectomized control rats. Similar protective effects were observed in the case of the skeletal system studies. Sesamol increased the bone ash content and the mechanical stress parameters in treated groups.

CONCLUSION

The results emphasize the involvement of oxidative stress and inflammation in the development of ovariectomy-induced pathophysiological changes and point towards the therapeutic potential of sesamol in menopausal pathologies.