Ginsenoside Rb1, a principal effective ingredient of Panax notoginseng, produces pain antihypersensitivity by spinal microglial dynorphin A expression.

Panax notoginseng (Chinese ginseng, Sanqi), one of the major ginseng species, has been traditionally used to alleviate different types of chronic pain. The raw P. notoginseng powder is commonly available in China as a non-prescription drug to treat various aliments including arthritic pain. However, strong scientific evidence is needed to illustrate its pain antihypersensitive effects, effective ingredients and mechanism of action. The oral P. notoginseng powder dose-dependently alleviated formalin-induced tonic hyperalgesia, and its total ginsenosides remarkably inhibited neuropathic pain hypersensitivity. Ginsenoside Rb1, the most abundant ginsenoside of P. notoginseng, dose-dependently produced neuropathic pain antihypersensitivity. Conversely, ginsenosides Rg1, Re and notoginseng R1, the other major saponins from P. notoginseng, failed to inhibit formalin-induced tonic pain or mechanical allodynia in neuropathic pain. Ginsenoside Rb1 metabolites ginsenosides Rg3, Compound-K and protopanaxadiol also had similar antineuropathic pain efficacy to ginsenoside Rb1. Additionally, intrathecal ginsenoside Rb1 specifically stimulated dynorphin A expression which was colocalized with microglia but not neurons or astrocytes in the spinal dorsal horn and primary cultured cells. Pretreatment with microglial metabolic inhibitor minocycline, dynorphin A antiserum and specific κ-opioid receptor antagonist GNTI completely blocked Rb1-induced mechanical antiallodynia in neuropathic pain. Furthermore, the specific glucocorticoid receptor (GR) antagonist Dex-21-mesylate (but not GPR30 estrogen receptor antagonist G15) also entirely attenuated ginsenoside Rb1-related antineuropathic pain effects. All these results, for the first time, show that P. notoginseng alleviates neuropathic pain and ginsenoside Rb1 is its principal effective ingredient. Furthermore, ginsenoside Rb1 inhibits neuropathic pain by stimulation of spinal microglial dynorphin A expression following GR activation.

Microglial Activation of GLP-1R Signaling in Neuropathic Pain Promotes Gene Expression Adaption Involved in Inflammatory Responses.

Background: Neuropathic pain is a common chronic pain, which is related to hypersensitivity to stimulus and greatly affects the quality of life of patients. Maladaptive gene changes and molecular signaling underlie the sensitization of nociceptive pathways. We previously found that the activation of microglial glucagon-like peptide 1 receptor (GLP-1R) could potently relieve formalin-, bone cancer-, peripheral nerve injury-, and diabetes-induced pain hypersensitivity. So far, little is known about how the gene profile changes upon the activation of GLP-1R signaling in the pathophysiology of neuropathic pain. Methods: Spinal nerve ligation (SNL) was performed to induce neuropathic pain in rats. Mechanical allodynia was assessed using von Frey filaments. The expression of IL-10, ß-endorphin, and µ-opioid receptor (MOR) was examined by real-time quantitative polymerase chain reaction (qPCR) and whole-cell recording. Measurements of cellular excitability of the substantia gelatinosa (SG) neurons by whole-cell recording were carried out. R packages of differential gene expression analysis based on the negative binomial distribution (DESeq2) and weighted correlation network analysis (WGCNA) were used to analyze differential gene expression and the correlated modules among GLP-1R clusters in neuropathic pain. Results: The GLP-1R agonist, exenatide, has an antiallodynic effect on neuropathic pain, which could be reversed by intrathecal injections of the microglial inhibitor minocycline. Furthermore, differential gene expression analysis (WGCNA) indicated that intrathecal injections of exenatide could reverse the abnormal expression of 591 genes in the spinal dorsal horn induced by nerve injury. WGCNA revealed 58 modules with a close relationship between the microglial GLP-1R pathway and features of nerve injuries, including pain, ligation, paw withdrawal latency (PWL), and anxiety. The brown module was identified as the highest correlated module, and the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that inflammatory responses were most correlated with PWL. To further unravel the changes of hyperalgesia-related neuronal electrophysiological activity mediated by microglia GLP-1 receptors, whole-cell recording identified that MOR agonism stimulated a robust outward current in the sham groups compared with the spinal nerve ligation (SNL) groups. This inhibitory effect on the SNL group was more sensitive than that of the sham group after bath application of ß-endorphin. Conclusions: Our results further confirmed that the GLP-1R pathway is involved in alleviating pain hypersensitivity mediated by spinal microglia activation, and inflammatory responses were the most correlated pathway associated with PWL changes in response to exenatide treatment. We found that the identification of gene regulation in response to GLP-1R activation is an effective strategy for identifying new therapeutic targets for neuropathic pain. Investigation for the activation of spinal microglial GLP-1R which might ameliorate inflammatory responses through gene expression and structural changes is providing a potential biomarker in pain management.

Thalidomide alleviates neuropathic pain through microglial IL-10/ß-endorphin signaling pathway.

Thalidomide is an antiinflammatory, antiangiogenic and immunomodulatory agent which has been used for the treatment of erythema nodosum leprosum and multiple myeloma. It has also been employed in treating complex regional pain syndromes. The current study aimed to reveal the molecular mechanisms underlying thalidomide-induced pain antihypersensitive effects in neuropathic pain. Thalidomide gavage, but not its more potent analogs lenalidomide and pomalidomide, inhibited mechanical allodynia and thermal hyperalgesia in neuropathic pain rats induced by tight ligation of spinal nerves, with ED50 values of 44.9 and 23.5 mg/kg, and Emax values of 74% and 84% MPE respectively. Intrathecal injection of thalidomide also inhibited mechanical allodynia and thermal hyperalgesia in neuropathic pain. Treatment with thalidomide, lenalidomide and pomalidomide reduced peripheral nerve injury-induced proinflammatory cytokines (TNFα, IL-1ß and IL-6) in the ipsilateral spinal cords of neuropathic rats and LPS-treated primary microglial cells. In contrast, treatment with thalidomide, but not lenalidomide or pomalidomide, stimulated spinal expressions of IL-10 and ß-endorphin in neuropathic rats. Particularly, thalidomide specifically stimulated IL-10 and ß-endorphin expressions in microglia but not astrocytes or neurons. Furthermore, pretreatment with the IL-10 antibody blocked upregulation of ß-endorphin in neuropathic rats and cultured microglial cells, whereas it did not restore thalidomide-induced downregulation of proinflammatory cytokine expression. Importantly, pretreatment with intrathecal injection of the microglial metabolic inhibitor minocycline, IL-10 antibody, ß-endorphin antiserum, and preferred or selective µ-opioid receptor antagonist naloxone or CTAP entirely blocked thalidomide gavage-induced mechanical antiallodynia. Our results demonstrate that thalidomide, but not lenalidomide or pomalidomide, alleviates neuropathic pain, which is mediated by upregulation of spinal microglial IL-10/ß-endorphin expression, rather than downregulation of TNFα expression.

Spinal microglial ß-endorphin signaling mediates IL-10 and exenatide-induced inhibition of synaptic plasticity in neuropathic pain.

AIM: This study aimed to investigate the regulation of pain hypersensitivity induced by the spinal synaptic transmission mechanisms underlying interleukin (IL)-10 and glucagon-like peptide 1 receptor (GLP-1R) agonist exenatide-induced pain anti-hypersensitivity in neuropathic rats through spinal nerve ligations. METHODS: Neuropathic pain model was established by spinal nerve ligation of L5/L6 and verified by electrophysiological recording and immunofluorescence staining. Microglial expression of ß-endorphin through autocrine IL-10- and exenatide-induced inhibition of glutamatergic transmission were performed by behavioral tests coupled with whole-cell recording of miniature excitatory postsynaptic currents (mEPSCs) and miniature inhibitory postsynaptic currents (mIPSCs) through application of endogenous and exogenous IL-10 and ß-endorphin. RESULTS: Intrathecal injections of IL-10, exenatide, and the µ-opioid receptor (MOR) agonists ß-endorphin and DAMGO inhibited thermal hyperalgesia and mechanical allodynia in neuropathic rats. Whole-cell recordings of bath application of exenatide, IL-10, and ß-endorphin showed similarly suppressed enhanced frequency and amplitude of the mEPSCs in the spinal dorsal horn neurons of laminae II, but did not reduce the frequency and amplitude of mIPSCs in neuropathic rats. The inhibitory effects of IL-10 and exenatide on pain hypersensitive behaviors and spinal synaptic plasticity were totally blocked by pretreatment of IL-10 antibody, ß-endorphin antiserum, and MOR antagonist CTAP. In addition, the microglial metabolic inhibitor minocycline blocked the inhibitory effects of IL-10 and exenatide but not ß-endorphin on spinal synaptic plasticity. CONCLUSION: This suggests that spinal microglial expression of ß-endorphin mediates IL-10- and exenatide-induced inhibition of glutamatergic transmission and pain hypersensitivity via presynaptic and postsynaptic MORs in spinal dorsal horn.

Microglial IL-10 and ß-endorphin expression mediates gabapentinoids antineuropathic pain.

Gabapentinoids are recommended first-line treatments for neuropathic pain. They are neuronal voltage-dependent calcium channel α2δ-1 subunit ligands and have been suggested to attenuate neuropathic pain via interaction with neuronal α2δ-1 subunit. However, the current study revealed their microglial mechanisms underlying antineuropathic pain. Intrathecal injection of gabapentin, pregabalin and mirogabalin rapidly inhibited mechanical allodynia and thermal hyperalgesia, with projected ED50 values of 30.3, 6.2 and 1.5 µg (or 176.9, 38.9 and 7.2 nmol) and Emax values of 66%, 61% and 65% MPE respectively for mechanical allodynia. Intrathecal gabapentinoids stimulated spinal mRNA and protein expression of IL-10 and ß-endorphin (but not dynorphin A) in neuropathic rats with the time point parallel to their inhibition of allodynia, which was observed in microglia but not astrocytes or neurons in spinal dorsal horns by using double immunofluorescence staining. Intrathecal gabapentin alleviated pain hypersensitivity in male/female neuropathic but not male sham rats, whereas it increased expression of spinal IL-10 and ß-endorphin in male/female neuropathic and male sham rats. Treatment with gabapentin, pregabalin and mirogabalin specifically upregulated IL-10 and ß-endorphin mRNA and protein expression in primary spinal microglial but not astrocytic or neuronal cells, with EC50 values of 41.3, 11.5 and 2.5 µM and 34.7, 13.3 and 2.8 µM respectively. Pretreatment with intrathecal microglial metabolic inhibitor minocycline, IL-10 antibody, ß-endorphin antiserum or µ-opioid receptor antagonist CTAP (but not κ- or δ-opioid receptor antagonists) suppressed spinal gabapentinoids-inhibited mechanical allodynia. Immunofluorescence staining exhibited specific α2δ-1 expression in neurons but not microglia or astrocytes in the spinal dorsal horns or cultured primary spinal cells. Thus the results illustrate that gabapentinoids alleviate neuropathic pain through stimulating expression of spinal microglial IL-10 and consequent ß-endorphin.

Protopanaxadiol alleviates neuropathic pain by spinal microglial dynorphin A expression following glucocorticoid receptor activation.

BACKGROUND AND PURPOSE: New remedies are required for the treatment of neuropathic pain due to insufficient efficacy of available therapies. This study provides a novel approach to develop painkillers for chronic pain treatment. EXPERIMENTAL APPROACH: The rat formalin pain test and spinal nerve ligation model of neuropathic pain were used to evaluate antinociception of protopanaxadiol. Primary cell cultures, immunofluorescence staining, and gene and protein expression were also performed for mechanism studies. KEY RESULTS: Gavage protopanaxadiol remarkably produces pain antihypersensitive effects in neuropathic pain, bone cancer pain and inflammatory pain, with efficacy comparable with gabapentin. Long-term PPD administration does not induce antihypersensitive tolerance, but prevents and reverses the development and expression of morphine analgesic tolerance. Oral protopanaxadiol specifically stimulates spinal expression of dynorphin A in microglia but not in astrocytes or neurons. Protopanaxadiol gavage-related pain antihypersensitivity is abolished by the intrathecal pretreatment with the microglial metabolic inhibitor minocycline, dynorphin antiserum or specific κ-opioid receptor antagonist GNTI. Intrathecal pretreatment with glucocorticoid receptor)antagonists RU486 and dexamethasone-21-mesylate, but not GPR-30 antagonist G15 or mineralocorticoid receptor antagonist eplerenone, completely attenuates protopanaxadiol-induced spinal dynorphin A expression and pain antihypersensitivity in neuropathic pain. Treatment with protopanaxadiol, the glucocorticoid receptor agonist dexamethasone and membrane-impermeable glucocorticoid receptor agonist dexamethasone-BSA in cultured microglia induces remarkable dynorphin A expression, which is totally blocked by pretreatment with dexamthasone-21-mesylate. CONCLUSION AND IMPLICATIONS: All the results, for the first time, indicate that protopanaxadiol produces pain antihypersensitivity in neuropathic pain probably through spinal microglial dynorphin A expression after glucocorticoid receptor activation and hypothesize that microglial membrane glucocorticoid receptor/dynorphin A pathway is a potential target to discover and develop novel painkillers in chronic pain.

Bulleyaconitine A Inhibits Morphine-Induced Withdrawal Symptoms, Conditioned Place Preference, and Locomotor Sensitization Via Microglial Dynorphin A Expression.

Bulleyaconitine A (BAA), a C19-diterpenoid alkaloid, has been prescribed as a nonnarcotic analgesic to treat chronic pain over four decades in China. The present study investigated its inhibition in morphine-induced withdrawal symptoms, conditioned place preference (CPP) and locomotor sensitization, and then explored the underlying mechanisms of actions. Multiple daily injections of morphine but not BAA up to 300 µg/kg/day into mice evoked naloxone-induced withdrawal symptoms (i.e., shakes, jumps, genital licks, fecal excretion and body weight loss), CPP expression, and locomotor sensitization. Single subcutaneous BAA injection (30-300 µg/kg) dose-dependently and completely attenuated morphine-induced withdrawal symptoms, with ED50 values of 74.4 and 105.8 µg/kg in shakes and body weight loss, respectively. Subcutaneous BAA (300 µg/kg) also totally alleviated morphine-induced CPP acquisition and expression and locomotor sensitization. Furthermore, subcutaneous BAA injection also specifically stimulated dynorphin A expression in microglia but not astrocytes or neurons in nucleus accumbens (NAc) and hippocampal, measured for gene and protein expression and double immunofluorescence staining. In addition, subcutaneous BAA-inhibited morphine-induced withdrawal symptoms and CPP expression were totally blocked by the microglial metabolic inhibitor minocycline, dynorphin A antiserum, or specific KOR antagonist GNTI, given intracerebroventricularly. These results, for the first time, illustrate that BAA attenuates morphine-induced withdrawal symptoms, CPP expression, and locomotor sensitization by stimulation of microglial dynorphin A expression in the brain, suggesting that BAA may be a potential candidate for treatment of opioids-induced physical dependence and addiction.

The spinal microglial IL-10/ß-endorphin pathway accounts for cinobufagin-induced mechanical antiallodynia in bone cancer pain following activation of α7-nicotinic acetylcholine receptors.

BACKGROUND: Cinobufagin is the major bufadienolide of Bufonis venenum (Chansu), which has been traditionally used for the treatment of chronic pain especially cancer pain. The current study aimed to evaluate its antinociceptive effects in bone cancer pain and explore the underlying mechanisms. METHODS: Rat bone cancer model was used in this study. The withdrawal threshold evoked by stimulation of the hindpaw was determined using a 2290 CE electrical von Frey hair. The ß-endorphin and IL-10 levels were measured in the spinal cord and cultured primary microglia, astrocytes, and neurons. RESULTS: Cinobufagin, given intrathecally, dose-dependently attenuated mechanical allodynia in bone cancer pain rats, with the projected Emax of 90% MPE and ED50 of 6.4 µg. Intrathecal cinobufagin also stimulated the gene and protein expression of IL-10 and ß-endorphin (but not dynorphin A) in the spinal cords of bone cancer pain rats. In addition, treatment with cinobufagin in cultured primary spinal microglia but not astrocytes or neurons stimulated the mRNA and protein expression of IL-10 and ß-endorphin, which was prevented by the pretreatment with the IL-10 antibody but not ß-endorphin antiserum. Furthermore, spinal cinobufagin-induced mechanical antiallodynia was inhibited by the pretreatment with intrathecal injection of the microglial inhibitor minocycline, IL-10 antibody, ß-endorphin antiserum and specific µ-opioid receptor antagonist CTAP. Lastly, cinobufagin- and the specific α-7 nicotinic acetylcholine receptor (α7-nAChR) agonist PHA-543613-induced microglial gene expression of IL-10/ß-endorphin and mechanical antiallodynia in bone cancer pain were blocked by the pretreatment with the specific α7-nAChR antagonist methyllycaconitine. CONCLUSIONS: Our results illustrate that cinobufagin produces mechanical antiallodynia in bone cancer pain through spinal microglial expression of IL-10 and subsequent ß-endorphin following activation of α7-nAChRs. Our results also highlight the broad significance of the recently uncovered spinal microglial IL-10/ß-endorphin pathway in antinociception.

Acupuncture/Electroacupuncture as an Alternative in Current Opioid Crisis.

Opioid drugs are the first line of defense in severe pain but the adverse effects associated with opioids are considered as a serious issue worldwide. Acupuncture/electroacupuncture is a type of Chinese medicine therapy which is an effective analgesic therapy, well documented in animals and human studies. Electroacupuncture stimulation could release endogenous opioid peptides causing analgesia in a variety of pain models. It can be used as an alternative therapy to control the opioid crisis.

Chitosan oligosaccharides prevent doxorubicin-induced oxidative stress and cardiac apoptosis through activating p38 and JNK MAPK mediated Nrf2/ARE pathway.

Doxorubicin (DOX) is one of the most effective chemotherapeutic drugs; however, the incidence of cardiotoxicity compromises its therapeutic index. Oxidative stress and apoptosis are believed to be involved in DOX-induced cardiotoxicity. Chitosan oligosaccharides (COS), the enzymatic hydrolysates of chitosan, have been reported to possess diverse biological activities including antioxidant and anti-apoptotic properties. The objective of the present study was to investigate the potential role of COS against DOX-induced cardiotoxicity, and the effects of COS on apoptosis and oxidative stress in rats and H9C2 cells. Furthermore, we also shed light on the involved pathways during the whole process. For this purpose, first, we demonstrated that COS exhibited a significant protective effect on cardiac tissue by not only inducing a decrease in body and heart growth but also ameliorated oxidative damage and ECG alterations in DOX-treated rats. Second, we found that COS reversed the decrease of cell viability induced by DOX, reduced the intracellular reactive oxygen species (ROS), increased the mitochondrial membrane potential (MMP) and Bcl-2/Bax ratio. COS treatment also results in reduced caspase-3 and caspase-9 expressions, and an increase in the phosphorylation of MAPKs (mitogen-activated protein kinases) in DOX-exposed H9C2 cells. Additionally, cellular homeostasis was re-established via stabilization of MAPK mediated nuclear factor erythroid 2-related factor 2/antioxidant-response element (Nrf2/ARE) signaling and transcription of downstream cytoprotective genes. In summary, these findings suggest that COS could be a potential candidate for the prevention and treatment of DOX-induced cardiotoxicity.

Novel Treatment of Experimental Autoimmune Prostatitis by Nanoparticle-Conjugated Autoantigen Peptide T2.

The exact etiology and pathogenesis of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) are still unknown, as a result, available therapeutic options for patients are far from satisfactory. Therefore, there is a need to develop a valid therapeutic approach that can ameliorate the manifestations of CP/CPPS. Fifty male C57BL/6 mice were randomly divided into five groups of ten mice each. All groups except naïve were subcutaneously injected with 0.2 ml of T2 plus complete Freund adjuvant (CFA) on day 0 and 14 to generate valid CP/CPPS model. After successful CP/CPPS induction, model group was injected with 0.2 ml of normal saline while PLGA, PLGA-OVA, and PLGA-T2 groups were administered intravenously with 0.2 ml mixture of PLGA, PLGA-OVA, and PLGA-T2, respectively. Voiding behavior, pain threshold, and hematoxylin and eosin staining were used to assess micturition habits, pain intensity as well as prostate inflammation. Additionally, TNF-α, CRP, and IL-10 levels in plasma were measured by using ELISA kits. Mice administered with PLGA-T2 showed higher pain threshold, lower urine frequencies, mild edema, and inflammation in prostate tissue in comparison to other groups. Moreover, the expression of TNF-α and CRP levels was markedly decreased while IL-10 expression was increased in the PLGA-T2 treatment group as compared to the other groups. Our results showed that nanoparticles conjugated with autoantigen novel peptide T2 could successfully alleviate or even heal CP/CPPS to some extent in mice. This study provides an easy, useful, and economic tool for ameliorating the manifestations of CP/CPPS that will improve the therapeutic approaches.

The protective effects of a novel synthetic ß-elemene derivative on human umbilical vein endothelial cells against oxidative stress-induced injury: Involvement of antioxidation and PI3k/Akt/eNOS/NO signaling pathways.

Antioxidant therapy is considered as promising strategy for treating oxidative stress-induced cardiovascular disease. Bis (ß-elemene-13-yl) glutarate (BEG) is a novel ß-elemene derivative. Herein, we examined the antioxidant activity of BEG on human umbilical vein endothelial cells (HUVECs) after injury with hydrogen peroxide (H2O2) and investigated the mechanism involved. HUVECs were divided into the following groups: control group (untreated cells); treated groups (cells treated with 0.1, 1, 10 µmol/L of BEG); positive control group (cells treated with 0.1 mM Vitamin E); model group (cells treated with 0.5 mM H2O2 alone). Cells were pre-incubated with or without BEG for 24 h and then incubated for a further 2 h with 0.5 mM H2O2. Our results showed that BEG significantly reduced H2O2 induced loss in endothelial cell viability, reactive oxygen species (ROS) production, reduced lactate dehydrogenase (LDH) release, and malonyldialdehyde (MDA) level in a concentration-dependent manner. Also, BEG increased the cellular the superoxide dismutase (SOD) activity. Moreover, we found that H2O2 decreased Akt and eNOS phosphorylation, which perhaps, indirectly reduced nitric oxide (NO) production. These effects induced by H2O2, however, were reduced by pre-treatment with BEG. BEG effects were inhibited by a PI3K inhibitor (wortmannin) and eNOS inhibitor (L-NAME). In conclusion, the present study demonstrated that BEG has antioxidant activity. Furthermore, BEG reduced H2O2-induced endothelial cells injury by the involvement of antioxidation and PI3K/Akt/eNOS/NO signaling pathways.

Role of oxidative stress in pathology of chronic prostatitis/chronic pelvic pain syndrome and male infertility and antioxidants function in ameliorating oxidative stress.

Oxidative stress (OS) is a result of the imbalance between reactive oxygen species (ROS) and antioxidants in the body that can cause tissue damage. Oxidative stress has a significant involvement in the pathogenesis of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) and male infertility. CP/CPPS is a major risk factor for male infertility due to generation of excessive ROS that damage sperm DNA, lipids, and proteins, resulting in compromised vitality and decreased sperm motility. Here we present a comprehensive review of oxidative stress relevance in CP/CPPS and male infertility, and embody the protective effects of antioxidants against ROS. An online literature was searched using the following keywords/terms: oxidative stress, ROS, Oxidative stress and chronic prostatitis, oxidative stress and male infertility and antioxidants. Original and review articles, clinical trials, and case reports of human and animal studies published till 2017 were searched using the PubMed and MEDLINE.

Antioxidant effects and mechanism of silymarin in oxidative stress induced cardiovascular diseases.

Cardiovascular diseases (CVDs) are considered as the major reason for mortality and morbidity worldwide. Substantial evidence suggests that increased oxidative stress plays a significant role in the pathogenesis of CVDs, including atherosclerosis, hypertension, vascular endothelial dysfunction and ischemic heart disease. Cellular oxidative stress results in the release of toxic free radicals by endothelial cells and vascular smooth muscle cells that interact with cell components such as protein, DNA or lipid resulting in cardiovascular pathology. Silymarin has antioxidant activities against CVDs and offers protection against oxidative stress-induced hypertension, atherosclerosis and cardiac toxicity. We present a comprehensive review regarding the oxidative stress and protective effects of silymarin in CVDs management. We also aim to provide mechanistic insight of the mechanisms of silymarin action in oxidative stress-induced CVDs.

Antioxidant therapy for management of oxidative stress induced hypertension.

Hypertension is considered as the most common risk factor for cardiovascular diseases, also is regarded as a leading cause of the mortality and morbidity worldwide. The mechanisms underlying the pathological process of hypertension are not completely explained. However, there is growing evidence that increased oxidative stress plays an important role in the pathophysiology of hypertension. Several preclinical studies and clinical trials have indicated that antioxidant therapy is important for management of hypertension, using antioxidants compounds such as alpha tocopherol (Vit E) and ascorbic acid (Vit C), polyphenols with others and some antihypertensive drugs that are now in clinical use (e.g. ACEIs, ARBs, novel B-blockers, dihydropyridine CCBs) which have antioxidative pleiotropic effects. The purpose of this review is to highlight the importance of antioxidant therapy for management of oxidative stress induced hypertension. Furthermore, we review the current knowledge in the oxidative stress and its significance in hypertension.