Effect of substituted stilbenes on platelet function

Unlocking the Potential of Pterostilbene: A Pharmaceutical Element for Aptamer-Based Nanomedicine

Natural compounds like pterostilbene (PTE) have gained recognition for their various biological activities and potential health benefits. However, challenges related to bioavailability and limited clinical efficacy have prompted efforts to strengthen their therapeutic potential. To meet these challenges, we herein rationally designed and successfully synthesized a pharmaceutical phosphoramidite that allows for the programmable incorporation of PTE into oligonucleotides. The resultant aptamer-PTE conjugate can selectively bind to cancer cells, leading to a specific internalization and drug release. Moreover, compared with free PTE, the conjugate exhibits superior cytotoxicity in cancer cells. Specifically, in a zebrafish xenograft model, the nanomedicine effectively inhibits tumor growth and neovascularization, highlighting its potential for targeted antitumor therapy. This approach presents a promising avenue for harnessing the therapeutic potential of natural compounds via a nanomedicine solution.

The Beneficial Effects of Pterostilbene on Post-Thawed Bovine Spermatozoa

Reactive Oxygen Species (ROS), primarily produced by cellular metabolism, are highly reactive molecules that modify cellular compounds. During sperm preparation in Assisted Reproductive Techniques (ARTs), intrinsic and extrinsic sources of ROS can impact spermatozoa's oxidative status. The modification of the media with compounds that enhance sperm quality characteristics is of great significance. The current study investigated the effect of pterostilbene, a phenolic compound, on bovine sperm quality. Cryopreserved spermatozoa from six bulls were thawed, supplemented with pterostilbene (0, 10 μΜ, 25 μΜ) and incubated for 60 min and 240 min. Spermatozoa were analyzed in terms of motility, viability, acrosomal status and intracellular concentration of superoxide anion in each time point. The incubation of spermatozoa with 25 μΜ pterostilbene resulted in the preservation of quality parameters through superoxide anion mitigation, while its presence in capacitating conditions resulted in higher percentage of acrosome-reacted spermatozoa. The results of the present study indicate that the addition of pterostilbene prevents oxidative insult to spermatozoa and preserves the sperm quality parameters.

Biotechnological Advances in Pharmacognosy and In Vitro Manipulation of Pterocarpus marsupium Roxb

Trees are vital resources for economic, environmental, and industrial growth, supporting human life directly or indirectly through a wide variety of therapeutic compounds, commodities, and ecological services. Pterocarpus marsupium Roxb. (Fabaceae) is one of the most valuable multipurpose forest trees in India and Sri Lanka, as it is cultivated for quality wood as well as pharmaceutically bioactive compounds, especially from the stem bark and heartwood. However, propagation of the tree in natural conditions is difficult due to the low percentage of seed germination coupled with overexploitation of this species for its excellent multipurpose properties. This overexploitation has ultimately led to the inclusion of P. marsupium on the list of endangered plant species. However, recent developments in plant biotechnology may offer a solution to the overuse of such valuable species if such advances are accompanied by technology transfer in the developing world. Specifically, techniques in micropropagation, genetic manipulation, DNA barcoding, drug extraction, delivery, and targeting as well as standardization, are of substantial concern. To date, there are no comprehensive and detailed reviews of P. marsupium in terms of biotechnological research developments, specifically pharmacognosy, pharmacology, tissue culture, authentication of genuine species, and basic gene transfer studies. Thus, the present review attempts to present a comprehensive overview of the biotechnological studies centered on this species and some of the recent novel approaches for its genetic improvement.

Pterostilbene, a Dimethylether Analogue of Resveratrol, Possesses High Potency in the Prevention of Platelet Activation in Humans and the Reduction of Vascular Thrombosis in Mice

Platelets play a crucial role in cardiovascular disorders (CVDs); thus, development of a therapeutic target that prevents platelet activation reduces CVDs. Pterostilbene (PTE) has several remarkable pharmacological activities, including anticancer and neuroprotection. Herein, we examined the inhibitory mechanisms of PTE in human platelets and its role in the prevention of vascular thrombosis in mice. At very low concentrations (1-5 μmol/L), PTE strongly inhibited collagen-induced platelet aggregation, but it did not have significant effects against thrombin and 9,11-dideoxy-11α,9α-epoxymethanoprostaglandin (U46619). PTE markedly reduced P-selectin expression on isolated α-granules by a novel microchip. Moreover, PTE inhibited adenosine triphosphate (ATP) release, intracellular ([Ca²⁺]i) mobilization (resting, 216.6 ± 14.0 nmol/L; collagen-activated platelets, 396.5 ± 25.7 nmol/L; 2.5 μmol/L PTE, 259.4 ± 8.8 nmol/L; 5 μmol/L PTE, 231.8 ± 9.7 nmol/L), phospholipase C (PLC)γ2/protein kinase C (PKC), Akt, and mitogen-activated protein kinase (MAPK) phosphorylation. Neither 9-(tetrahydro-2-furanyl)-9H-purin-6-amine (SQ22536) nor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) reversed platelet aggregation inhibited by PTE. PTE did not affect vasodilator-stimulated phosphoprotein phosphorylation. In mice, PTE obviously reduced the mortality (from 100 to 37.5%) associated with acute pulmonary thromboembolism without increasing the bleeding time. Thus, PTE could be used to prevent CVDs.

The Antithrombotic Agent Pterostilbene Interferes with Integrin αIIbβ3-Mediated Inside-Out and Outside-In Signals in Human Platelets

Platelets play a crucial role in the physiology of primary hemostasis and pathological processes such as arterial thrombosis; thus, developing a therapeutic target that prevents platelet activation can reduce arterial thrombosis. Pterostilbene (PTE) has remarkable pharmacological activities, including anticancer and neuroprotection. Few studies have reported the effects of pterostilbene on platelet activation. Thus, we examined the inhibitory mechanisms of pterostilbene in human platelets and its role in vascular thrombosis prevention in mice. At low concentrations (2–8 μM), pterostilbene strongly inhibited collagen-induced platelet aggregation. Furthermore, pterostilbene markedly diminished Lyn, Fyn, and Syk phosphorylation and hydroxyl radical formation stimulated by collagen. Moreover, PTE directly hindered integrin α_IIbβ₃ activation through interfering with PAC-1 binding stimulated by collagen. In addition, pterostilbene affected integrin α_IIbβ₃-mediated outside-in signaling, such as integrin β₃, Src, and FAK phosphorylation, and reduced the number of adherent platelets and the single platelet spreading area on immobilized fibrinogen as well as thrombin-stimulated fibrin clot retraction. Furthermore, pterostilbene substantially prolonged the occlusion time of thrombotic platelet plug formation in mice. This study demonstrated that pterostilbene exhibits a strong activity against platelet activation through the inhibition of integrin α_IIbβ₃-mediated inside-out and outside-in signaling, suggesting that pterostilbene can serve as a therapeutic agent for thromboembolic disorders.

Can diet modulate trimethylamine N-oxide (TMAO) production? What do we know so far?

BACKGROUND

Trimethylamine N-oxide (TMAO) is a metabolite that has attracted attention due to its positive association with several chronic non-communicable diseases such as insulin resistance, atherosclerotic plaque formation, diabetes, cancer, heart failure, hypertension, chronic kidney disease, liver steatosis, cardiac fibrosis, endothelial injury, neural degeneration and Alzheimer's disease. TMAO production results from the fermentation by the gut microbiota of dietary nutrients such as choline and carnitine, which are transformed to trimethylamine (TMA) and converted into TMAO in the liver by flavin-containing monooxygenase 1 and 3 (FMO1 and FMO3). Considering that TMAO is involved in the development of many chronic diseases, strategies have been found to enhance a healthy gut microbiota. In this context, some studies have shown that nutrients and bioactive compounds from food can modulate the gut microbiota and possibly reduce TMAO production.

OBJECTIVE

This review has as main objective to discuss the studies that demonstrated the effects of food on the reduction of this harmful metabolite.

METHODS

All relevant articles until November 2020 were included. The articles were searched in Medline through PubMed.

RESULTS

Both the food is eaten acutely and chronically, by altering the nature of the gut microbiota, influencing colonic TMA production. Furthermore, hepatic production of TMAO by the flavin monooxygenases in the liver may also be influenced by phenolic compounds present in foods.

CONCLUSION

The evidence presented in this review shows that TMAO levels can be reduced by some bioactive compounds. However, it is crucial to notice that there is significant variation among the studies. Further clinical studies should be conducted to evaluate these dietary components' effectiveness, dose, and intervention time on TMAO levels and its precursors.

Therapeutic potential of prenylated stilbenoid macasiamenene F through its anti-inflammatory and cytoprotective effects on LPS-challenged monocytes and microglia

ETHNOPHARMACOLOGICAL RELEVANCE

Macaranga Thou. (Euphorbiaceae) is a large genus that comprises over 300 species distributed between Western Africa and the islands of the South Pacific. Plants of this genus have a long-standing history of use in traditional medicine for different purposes, including the treatment of inflammation. Fresh and dried leaves of certain Macaranga species (e.g. M. tanarius (L.) Müll.Arg.), have been used to treat cuts, bruises, boils, swellings, sores and covering of wounds in general. Several reports described Macaranga spp. being a rich source of polyphenols, such as prenylated stilbenoids and flavonoids, mostly responsible for its biological activity. Similarly, an abundant content of prenylated stilbenes was also described in M. siamensis S.J.Davies, species recently identified (2001) in Thailand. While the respective biological activity of the prenylated stilbenes from M. siamensis was poorly investigated to date, our recent study pointed out the interest as the natural source of several novel anti-inflammatory stilbenoids isolated from this species.

AIM OF THE STUDY

This work investigated the potential anti-inflammatory effects of the stilbenoid macasiamenene F (MF) isolated from M. siamensis S.J.Davies (Euphorbiaceae) on the lipopolysaccharide (LPS)-induced inflammation-like response of monocytes and microglia, major cells involved in the peripheral and central inflammatory response, respectively.

MATERIALS AND METHODS

LPS-induced stimulation of TLR4 signaling led to the activation of inflammatory pathways in in vitro models of THP-1 and THP-1-XBlue™-MD2-CD14 human monocytes, BV-2 mouse microglia, and an ex vivo model of brain-sorted mouse microglia. The ability of the stilbenoid MF to intervene in the IкB/NF-кB and MAPKs/AP-1 inflammatory cascade was investigated. The gene and protein expressions of the pro-inflammatory cytokines IL-1β and TNF-α were evaluated at the transcription and translation levels. The protective effect of MF against LPS-triggered microglial loss was assessed by cell counting and the LDH assay.

RESULTS

MF demonstrated beneficial effects, reducing both monocyte and microglial inflammation as assessed in vitro. It efficiently inhibited the degradation of IкBα, thereby reducing the NF-кB activity and TNF-α expression in human monocytes. Furthermore, the LPS-induced expression of IL-1β and TNF-α in microglia was dampened by pre-, co-, or post-treatment with MF. In addition to its anti-inflammatory effect, MF demonstrated a cytoprotective effect against the LPS-induced death of BV-2 microglia.

CONCLUSION

Our research into anti-inflammatory and protective effects of MF has shown that it is a promising candidate for further in vitro and in vivo investigations of MF interventions with respect to acute and chronic inflammation, including potentially beneficial effects on the inflammatory component of brain diseases such as stroke and Alzheimer's disease.

Evaluation of the status quo of polyphenols analysis: Part I-phytochemistry, bioactivity, interactions, and industrial uses

Phytochemicals, especially polyphenols, are gaining more attention from both the scientific community and food, pharmaceutical, and cosmetics industries due to their implications in human health. In this line, lately new applications have emerged, and of great importance is the selection of accurate and reliable analytical methods for better evaluation of the quality of the end-products, which depends on diverse process variables as well as on the matrices and on the physicochemical properties of different polyphenols. The first of a two-part review on polyphenols will address the phytochemistry and biological activities of different classes of polyphenols including flavonoids, lignans and flavanolignans, stilbenoids, tannins, curcuminoids, and coumarins. Moreover, the possible interactions of polyphenols and current and potential industrial applications of polyphenols are discussed.

Plasma pharmacokinetics of isorhapontigenin, a novel derivative of stilbenes, in mice by LC-MS/MS method

Isorhapontigenin (ISO), a novel derivative of stilbene compound, possessess good pharmacological activities such as antiviral, antioxidant, and anticancer. The purpose of this study is to investigate the pharmacokinetic of ISO in mice plasma, after oral administration of three doses (40, 80, and 160 mg/kg). Isorhapontigenin was detected by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and a reliable LC-MS/MS assay for ISO in mice plasma was developed. The method was linear over a concentration range of 5-2000 ng/ml, and the lower limit of quantification was 5 ng/ml. The results indicated that there was a linear relationship between AUC_(0-t), AUC_(0-∞), and C_max of ISO and dosages. ISO underwent quick absorption and elimination in mice.

Effects of combined therapy with resveratrol, continuous and interval exercises on apoptosis, oxidative stress, and inflammatory biomarkers in the liver of old rats with non-alcoholic fatty liver disease

CONTEXT

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disorder.

OBJECTIVE

Effects of combined therapy with resveratrol, interval and continuous exercises on oxidative stress, inflammation, and apoptosis in the liver of rats with NAFLD.

METHODS

NAFLD rats were organised in patient, saline, resveratrol (RSV), continuous exercise, interval exercise, continuous exercise + RSV, and interval exercise + RSV groups.

RESULTS

Resveratrol supplementation alone or in combination with interval and continuous training significantly decreased malondialdehyde and TNF-α level (p < .05), while the levels of catalase; superoxide dismutase and IL-10 were significantly increased (p < .05). Although RSV alone significantly decreased the percentage of apoptotic cells (17.12%), its combination with interval (10.74%), and continuous (14.85%) exercise training demonstrated higher anti-apoptotic activity (p < .05).

CONCLUSIONS

Although resveratrol alone has an antioxidant, anti-apoptotic and anti-inflammatory properties, combined therapy with interval, and continuous training can be more effective to mitigate these abnormalities in NAFLD patients.

A Review of Antiplatelet Activity of Traditional Medicinal Herbs on Integrative Medicine Studies

Thrombotic events mainly occurred by platelet activation and aggregation. The vascular occlusion causes serious disease states such as unstable angina, ischemic stroke, and heart attack. Due to the pervading of thrombotic diseases, new antiplatelet drugs are necessary for preventing and treating arterial thrombosis without adverse side effects. Traditional medicinal herbs have been used for the treatment of human ailments for a long time. The clinically useful and safe products from traditional medicinal herbs were identified and developed in numerous pharmacological approaches. A complementary system of traditional medicinal herbs is a good candidate for pharmacotherapy. However, it still has a limitation in its function and efficacy. Thus, it is necessary to study the mode of action of traditional medicinal herbs as alternative therapeutic agents. In this review, we focused on our current understanding of the regulatory mechanisms of traditional medicinal herbs in antiplatelet activity and antithrombotic effect of traditional medicinal herbs on platelet function.

In vivoformed metabolites of polyphenols and their biological efficacy

The metabolites of polyphenols are antioxidant, anti-inflammatory and anticancer agents. Being bioavailable, they may play an important role in preventing degenerative diseases.

Effects of resveratrol, exercises and their combination on Farnesoid X receptor, Liver X receptor and Sirtuin 1 gene expression and apoptosis in the liver of elderly rats with nonalcoholic fatty liver

Background

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disorder. This study aims to consider effects of resveratrol, exercise and their combination on Farnesoid X receptor (Fxr), the liver X receptor (Lxr) and Sirtuin 1 (Sirt 1) genes expression in the liver of elderly rats with NAFLD.

Methods

Rats with NAFLD were randomly divided into seven groups including patient, saline, resveratrol (RSV), interval exercise, continuous exercise, interval exercise + RSV and continuous exercise + RSV. Levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) in the liver tissue were measured using specific ELISA kits. A TUNEL assay kit was used for the assessment of hepatic cells apoptosis. Lipid profiles were considered by measuring the serum triglyceride, cholesterol, LDL, and HDL. Expression of Sirt1, Lxr and Fxr genes was considered using RT-PCR.

Results

Resveratrol administration alone or combined with exercise training significantly improved the expression of Sirt1, Lxr and Fxr genes (p < 0.05) in the hepatic tissue of rats with NAFLD, while levels of AST, ALT, ALP enzymes, as well as apoptotic cells were significantly decreased (p < 0.05).

Discussion

Although resveratrol alone improves the expression of Sirt1, Lxr and Fxr, as well as liver function, combined therapy with exercise training is more effective to improve NAFLD.

Medicinal plants with antithrombotic property in Persian medicine: a mechanistic review

Thrombosis is one of the major causes of morbidity and mortality in a wide range of vessels diseases. Due to the high prevalence of thromboembolic disorders investigations are being carried out on new antithrombotic agents with limited adverse side effects in which herbal medicines are considered as alternative remedies. Persian medicine (PM) as a traditional medicine has a good potential for pharmacotherapy based on its own principles and development of drugs via investigating PM literature. In PM manuscripts there are some concepts that express the management of blood clots and antithrombotic properties. This study reviewed the pharmacological effects of medicinal plants mentioned in PM literature for blood clot management in light of current knowledge. Plants mentioned in PM for management of blood clot belong to 12 families in which Apiaceae, Lamiaceae and Compositae were the most repeated ones. Among the proposed plants Allium sativum, Rosmarinus officinalis, Boswellia serrata, Sesamum indicum, Matricaria chamomilla and Carthamus tinctorius have been the most researched plants in modern antithrombotic studies while for some plants such as Helichrysum stoechas, Dracocephalum kotschi, Carum carvi, Bunium persicum and Lagoecia cuminoides no evidence could be found. One of the interesting notes in clot management in PM texts was introducing the target organ for some of the recommended herbs like Carum carvi and Bunium persicum for dissolving blood clot in stomach and Commiphora mukul for thrombosed hemorrhoid. It seems review of PM recommendations can help to design future researches for antithrombotic drugs discovering with more effectiveness and safety.

Biological Activities of Stilbenoids

Stilbenoids are a group of naturally occurring phenolic compounds found in various plant species. They share a common backbone structure known as stilbene, but differ in the nature and position of substituents. Stilbenoids are classified as phytoalexins, which are antimicrobial compounds produced de novo in plants to protect against fungal infection and toxins. In this review, the biological effects of stilbenoids such as resveratrol, pterostilbene, gnetol and piceatannol are discussed. Stilbenoids exert various biological activities ranging from cardioprotection, neuroprotection, anti-diabetic properties, depigmentation, anti-inflammation, cancer prevention and treatment. The results presented cover a myriad of models, from cell culture to animal studies as well as clinical human trials. Although positive results were obtained in most cell culture and animal studies, further human studies are needed to substantiate beneficial effects of stilbenoids. Resveratrol remains the most widely studied stilbenoid. However, there is limited information regarding the potential of less common stilbenoids. Therefore, further research is warranted to evaluate the salutary effects of various stilbenoids.

Resveratrol improves alcoholic fatty liver disease by downregulating HIF-1α expression and mitochondrial ROS production

Oxidative stress has been demonstrated to be involved in the etiology of alcoholic fatty liver disease (AFLD). Previous studies had demonstrated that resveratrol (RES) could reduce oxidative stress by different mechanisms. However, the effect of RES on alcohol-induced fatty liver remains unclear. In the present study, a total of 48 male SD rats were divided into three groups: Control, AFLD, and RES groups. Rats were administered with either nothing or 65% vol/vol alcohol (5 ml/kg/day in the first three days, and then 10 ml/kg/day in the following days) with or without RES supplementation (250 mg/kg/day) for 4 weeks. Blood and liver tissue samples were collected and subjected to biochemical assays, histological examination, Western blot, and mitochondrial radical oxygen species (ROS) assays. In RES group, significant decreases in serum ALT and AST concentrations, fat deposition, triglyceride (TG) content, HIF-1α protein expression as well as mitochondrial ROS production in liver were observed when compared with AFLD group (all p <0.05). These results indicated that RES could alleviate the liver injury induced by alcohol and prevent the progression of AFLD. Down regulation of HIF-1α protein expression and mitochondrial ROS production in liver might be, at least part of, the underlying mechanisms.

Improvement of Blood Rheology by Extract of Asana, Pterocarpus marsupium -Suppression of Platelet Aggregation Activity and Pterostilbene, as a Main Stilbene in the Extract

The decoction from a tumbler made of heartwood of the Indian kino tree (Asana, Pterocarpus marsupium, PM) was a remedy for diabetes mellitus in Ayurveda. Diabetes mellitus is a one of the lifestyle-related diseases that finally leads to the induction of fatal diseases such as arterial sclerosis and cerebral infarction. In this study, effects on blood fluidity was investigated using extract obtained from the heartwood of PM. Oral administration of the extract reduced passage time of the blood obtained from disseminated intravascular coagulation model rats. In addition, the extract inhibited the reduction of platelets, which suggests that this attributed to the inhibition of platelet aggregation. The extract also demonstrated suppressive effects on both collagen- and arachidonic acid-induced platelet aggregation. Moreover, the extract showed inhibition against cyclooxygenase. The active principle was determined to be pterostilbene by collagen-induced platelet aggregation inhibitory activity-guided purification. Pterostilbene is a derivative of resveratrol, which is known to be in red wine and to possess beneficial effects for prevention of life-style related diseases. Pterostilbene exhibited 56 and 57% inhibition on both collagen- and arachidonic acid-induced platelet aggregation at 20 μM, respectively. These results demonstrate that the extract of PM heartwood may be a promising candidate as a multifunctional agent for treating lifestyle-related diseases.

Bioactive polyphenols and cardiovascular disease: chemical antagonists, pharmacological agents or xenobiotics that drive an adaptive response?

Polyphenols are widely regarded to have a wide range of health-promoting qualities, including beneficial effects on cardiovascular disease. Historically, the benefits have been linked to their well-recognized powerful antioxidant activity. However, the concept that the beneficial effects are attributable to direct antioxidant activity in vivo does not pay sufficient heed to the fact that polyphenols degrade rapidly, are poorly absorbed and rapidly metabolized, resulting in very low bioavailability. This review explores alternative mechanisms by which polyphenols, or their metabolites, exert biological activity via mechanisms that can be activated by physiologically relevant concentrations. Evidence is presented to support the action of phenolic derivatives on receptors and signalling pathways to induce adaptive responses that drive changes in endogenous antioxidant, antiplatelet, vasodilatory and anti-inflammatory effects. The implications are that in vitro antioxidant measures as predictors of polyphenol protective activity in vivo hold little relevance and that closer attention needs to be paid to bioavailable metabolites to understand the mode of action of these diet-derived components.

LINKED ARTICLES

This article is part of a themed section on Principles of Pharmacological Research of Nutraceuticals. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.11/issuetoc.

Promising therapeutic potential of pterostilbene and its mechanistic insight based on preclinical evidence

Pterostilbene (PS) is a well-recognized antioxidant that primarily exists in blueberries, grapevines and heartwood of red sandalwood. Interest in this compound has been renewed in recent years, and studies have found that PS possesses an array of pharmacological properties, including chemopreventive, antiinflammatory, antidiabetic, antidyslipidemic, antiatherosclerotic and neuroprotective effects. However, the greater in vivo bioavailability of PS, as compared to resveratrol, is an added advantage for its efficacy. This review provides a summary regarding the sources, pharmacokinetic aspects and pharmacodynamics of PS, with a focus on the molecular mechanisms underlying its protective effects against cancer, brain injuries and heart disease. Studies regarding the safety profile of PS have also been included. Based on the presently available evidence, we conclude that PS represents an active phytonutrient and a potential drug with pleiotropic health applications.

Resveratrol Reduces the Incidence of Portal Vein System Thrombosis after Splenectomy in a Rat Fibrosis Model

Purpose. To investigate the preventive effect of resveratrol (RES) on the formation of portal vein system thrombosis (PVST) in a rat fibrosis model. Methods. A total of 64 male SD rats, weighing 200–300 g, were divided into five groups: Sham operation, Splenectomy I, Splenectomy II, RES, and low molecular weight heparin (LMWH), with the former two groups as nonfibrosis controls. Blood samples were subjected to biochemical assays. Platelet apoptosis was measured by flow cytometry. All rats were euthanized for PVST detection one week after operation. Results. No PVST occurred in nonfibrosis controls. Compared to Splenectomy II, the incidences of PVST in RES and LMWH groups were significantly decreased (both p < 0.05). Two rats in LMWH group died before euthanasia due to intra-abdominal hemorrhage. In RES group, significant decreases in platelet aggregation, platelet radical oxygen species (ROS) production, and increase in platelet nitric oxide (NO) synthesis and platelet apoptosis were observed when compared with Splenectomy II (all p < 0.001), while in LMWH group only significant decrease in platelet aggregation was observed. Conclusion. Prophylactic application of RES could safely reduce the incidence of PVST after splenectomy in cirrhotic rat. Regulation of platelet function and induction of platelet apoptosis might be the underlying mechanisms.